artculo ambientaal
TRANSCRIPT
-
8/9/2019 artculo ambientaal
1/8
Journal of Hazardous Materials 279 (2014) 322329
Contents lists available at ScienceDirect
Journal ofHazardous Materials
j ournal homepage: www.elsevier .com/ locate / jhazmat
New approach to solar photo-Fenton operation. Raceway ponds astertiary treatment technology
Irene Carra a,b, Lucas Santos-Juanes a,b, Francisco Gabriel Acin Fernndeza,Sixto Malato b,c,Jos Antonio Snchez Prez a,b,
a Department of Chemical Engineering, University of Almera, 04120,Almera, Spainb CIESOL, Joint Centre of theUniversity of Almera-CIEMAT, 04120,Almera, Spainc Plataforma Solar de Almera (CIEMAT), 04200, Tabernas, Almera, Spain
h i g h l i g h t s
Raceway ponds are used for the first
time as photo-Fenton reactors. Raceway ponds are effective and have
high treatment capacity (48 mg/h m2
for 360 L). The highest treatment capacity
occurs with 5.5 mg Fe/L and 15cm
liquid depth. Low iron concentrations are enough
to oxidise the pesticide mixture. Raceway ponds are a simple and low-
cost alternative for micropollutant
removal.
g r a p h i c a l a b s t r a c t
a r t i c l e i n f o
Article history:
Received 28 May 2014
Received in revised form 8 July 2014
Accepted 9 July 2014
Available online 17 July 2014
Keywords:
Acetamiprid
Thiabendazol
Photoreactor
Treatment capacity
Micropollutant degradation
a b s t r a c t
The photo-Fenton process has proven its efficiency in the removal ofmicropollutants. However, the high
costs usually associated with it prevent a spread ofthis technology. An important factor affecting costs is
the kind ofphotoreactor used, usually tubular with a reflecting surface. Tubular reactors like compound
parabolic collectors, CPCs, involve high capital costs. In comparison, the application ofless costly reactors
such as the extensive raceway ponds (RPRs) would help to spread the use ofthe photo-Fenton process
as tertiary treatment at commercial scale. As far as the authors know, RPRs have never been used in
advanced oxidation processes (AOPs) applications. This work isaimed at studying the applicability ofRPRs
to remove micropollutants with solar photo-Fenton. For this purpose, a pesticide mixture ofcommercial
acetamiprid (ACTM) and thiabendazole (TBZ) (100g/Leach) was used in simulated secondary effluent.
Iron concentration (1, 5.5 and 10 mg/L) and liquid depth (5, 10 and 15 cm) were studied as process
variables. TBZ was removed at the beginning ofthe treatment (less than 5 min), although ACTM removal
times were longer (2040 min for the highest iron concentrations). High treatment capacity per surface
area was obtained (48 mg/h m2 with 5.5 mg Fe/Land 15 cm liquid depth), proving the feasibility ofusingRPRs for micropollutant removal.
2014 Elsevier B.V. All rights reserved.
Corresponding author at: Department of Chemical Engineering, University of
Almera, 04120, Almera, Spain. Tel.: +34 950015314; fax: +34 950015484.
E-mail address:[email protected] (J.A. Snchez Prez).
1. Introduction
The detection of low concentration (g/Lng/L) of persistentpollutants, also called micropollutants, in aquatic systems has
drawn the attention of the scientific community in recent years.
http://dx.doi.org/10.1016/j.jhazmat.2014.07.010
0304-3894/ 2014 Elsevier B.V. All rightsreserved.
http://localhost/var/www/apps/conversion/tmp/scratch_1/dx.doi.org/10.1016/j.jhazmat.2014.07.010http://www.sciencedirect.com/science/journal/03043894http://www.elsevier.com/locate/jhazmatmailto:[email protected]://localhost/var/www/apps/conversion/tmp/scratch_1/dx.doi.org/10.1016/j.jhazmat.2014.07.010http://localhost/var/www/apps/conversion/tmp/scratch_1/dx.doi.org/10.1016/j.jhazmat.2014.07.010mailto:[email protected]://crossmark.crossref.org/dialog/?doi=10.1016/j.jhazmat.2014.07.010&domain=pdfhttp://www.elsevier.com/locate/jhazmathttp://www.sciencedirect.com/science/journal/03043894http://localhost/var/www/apps/conversion/tmp/scratch_1/dx.doi.org/10.1016/j.jhazmat.2014.07.010 -
8/9/2019 artculo ambientaal
2/8
I. Carra et al. / Journal of HazardousMaterials 279 (2014) 322329 323
Certainly, small amounts of common substances such as caffeine,
nicotine and pharmaceuticals, among others, have been detected
in surface waters such as lakes or rivers [13].
Urban wastewater treatment plants (WWTPs) are usually based
on biological treatments which are not effective in micropollutant
removal [4,5]. Likewise, WWTPs may also receive effluents from
industries with specific contamination. For instance, effluents can
easily contain low concentration of pollutants such as pesticides,
which are used in crops [6]. The small amounts in which micropol-
lutants are found in WWTP effluents can be hazardous for aquatic
systems, and their accumulation results eventually in chronic tox-
icity and other effects of environmental concern. In this regard,
advanced oxidation processes (AOPs) arise as an effective alterna-
tivethanks to the oxidationof micropollutants by hydroxylradicals
[7]. Indeed, AOPs efficiency in micropollutant removal makes them
firm candidates for tertiary treatment. Ozonation, heterogeneous
and homogeneous photocatalysis are some of the AOPs whichhave
already been studied in this sense with successful results [8,9].
Specifically, homogeneous photocatalysis or photo-Fenton process
has provento bevery efficientin this regard[10]. In this process, the
generation of radicals is catalysed by iron, with hydrogen peroxide
as the oxidant. Iron is cyclically reduced and oxidised in a redox
cycle. The oxidationtakes place in a fast reaction represented in Eq.
(1). Its reduction, though, can take place in the presence of UVvisirradiance (Eq. (2)) or in the dark (Eq. (3)). The presence of UVvis
irradiance enhances the process rate though, since Reaction (2) is
faster thanReaction(3). This factimplies thatirradiance absorption
is essential to the process performance.
Fe2++H2O2 Fe3++HO+HO (1)
Fe3++H2O+hv Fe2++HO+H+ (2)
Fe3++H2O2 Fe2++HO2
+H+ (3)
Nevertheless, the main drawback in the application of these
techniques at commercial scale is the cost. The operating costs in
the case of the photo-Fenton process may be reduced with the
use of solar light. Even so, amortisation costs are its main weak-
ness. Two factors are crucial: photoreactor cost and reaction time[11]. With regard to the first factor, the most popular photoreac-
tors are compound parabolic collectors (CPCs), developed for these
applications at the end of the nineties [12]. They are constituted by
borosilicate glasstubeson the axis of a compoundparabolic surface
(madeof aluminium).The cost forthe installation andpurchase of a
large scale CPC plant for solar photo-Fenton has been estimated as
400D/m2, including pumps, piping and accessories (Final results of
CADOX Project,Contract n EVK1-CT2002-00122) [13]. Withregard
to reaction time, long process times increase the solar collector
surface needed and energy consumption for pumping, thus, rais-
ing the costs. In this sense, 80W/m3 was reported for a 104m2
photo-Fenton plant with solar compound parabolic collectors [11].
The use of photoreactors such as CPCs comes from the need of
making the most of the solar beams that reach the system. Photoncapture is crucial whenthe need ofhydroxylradicals is largesuchas
for macropollutant (mg/Lg/L) removal, as is the case of industrial
wastewater [14]. When the treatment is aimed at micropollutant
oxidationthough, the pollutant concentrationis at leasta thousand
times lower than for macropollutant oxidation. Therefore, the pro-
cess needs less hydroxyl radicals and, consequently, less irradiance
(less photons) to achieve removal [15]. From this arises the ques-
tion whether other kind of photoreactors, less efficient in photon
capture andmore simple, could be usedfor micropollutant removal.
An interesting choice would be an extensive and non-
concentrating reactor. Some examples are the Thin Film Fixed
Bed Reactor (TFFBR) or Double Skin Sheet Reactor (DSSR) [16].
Also, shallow pond configurations and flat-plate reactors were
studied in the nineties [1820]. All of them were mainly tried for
macropollutants degradation with TiO2. Nevertheless few cases
have been published for photo-Fenton applications, Rosseti et al.,
modelled formic acid degradation in a flat-plate reactor [21]. Sim-
ilar to this kind of reactors are the Raceway Pond Reactors (RPRs),
which have been widely applied for microalgal mass culture [22].
In RPRs the liquid depth can be varied and the flow is controlled.
They are extensive reactors withchannels through which the water
is recirculated. They are made of low cost materials, mainly plastic
liners, giving rise to low construction costs of about 100,000 D/ha,
that is 10 D/m2 [23]. Additionally, the power requirements for
mixing are also small over 4 W/m3. Due to their flexibility
and easy scale-up, raceway reactors are the most used devices
for microalgal applications [22] and production costs have been
reported to be markedly lower than for tubular photobioreactors,
such is the case for fuel production from microalgae [24,25] and
much lower than CPCs. Effective, extensive and low-cost (per
surface unit) photoreactors such as RPRs would spread the use of
the photo-Fenton process as tertiary treatment.
In the light of these facts this work was aimed at studying the
applicability of extensive RPRs to remove micropollutants with
solar photo-Fenton. For this purpose, a mixture of commercial
pesticides, acetamiprid (ACTM) and thiabendazole (TBZ), 100g/Leach, was used in simulated secondary effluent as model pollutant
mixture, avoiding the disturbance of daily variations in real efflu-ents. Both pesticides are commonly applied to citrus crops in the
Mediterranean area. To assess the best process conditions, first the
effect of iron concentration (1, 5.5 and 10mg/L) and liquid depth
(5,10 and15 cm, which correspondedto the same illuminatedarea
but different water volume, up to 360L) was studied using tap
water as matrix instead of simulated secondary effluent to avoid
disturbances due to other organics but with a ionic composition
close to secondary effluents. Results were confirmed in simulated
secondary effluent.
2. Materials and methods
2.1. Chemicals
Sulphuric acid (9597%) and hydrogen peroxide (35%) were
obtained from J.T. Baker and ferrous sulphate (99%) from Fluka.
CaSO42H2O, MgSO4, KCl, (NH4)2SO4, NaHCO3, beef extract,
peptone, humic salts, sodium lignin sulfonate, sodium lauryle
sulphate, acacia gum powder, formic acid and Arabic acid were
acquired from SigmaAldrich. Commercial formulations of pesti-
cides were used: EPIK (20%, w/w ACTM) and TEXTAR (60%, w/v
TBZ). HPLC grade acetonitrile from Carlo Erba Reagents andMilli-Q
grade water were used in the chromatographic analysis.
2.2. Experimental set-up
Theexperiments were carried outin a fibreglass-RPR pilot plantat pH 2.8. This pH value was chosen because it is the optimum
for the photo-Fenton process [22] and allows a higher solubility
of iron, allowing evaluating properly the efficiency of RPRs. Future
work will be focused on working at circumneutral pH in RPRs, rec-
ommended to treat micropollutants [26]. The fibreglass-RPR has
a maximum capacity of 360 L , a length of 3.85 m and width of
0.64m. It is separated by a central wall, forming two canals. The
RPR includes a paddle wheel connected to an engine to obtain a
mixed and homogeneous system. The engine was linked to a vari-
able frequency drive to control the paddles speed. A scheme of the
plant is presented in Fig. 1.
Iron concentration and liquid depth (treated volume) were the
process variables studied. A one-factor-at-a-time strategy was
followed, changing an individual variable and keeping the other
-
8/9/2019 artculo ambientaal
3/8
324 I. Carra et al. / Journal of HazardousMaterials 279 (2014) 322329
Fig. 1. RPR scheme.
one constant. Iron concentration was kept to low values, from 1
to 10mg/L, typically used for micropollutant removal [27,28]. Low
concentrations of iron contribute to prevent large generation of
iron sludge when neutralising the effluent after the treatment.
Liquid depth, which determines irradiance path length, was varied
from 5 cm to 15 cm. The first value was taken as the common
diameter used in tubular reactors such as CPCs [29]. The last depthvalue is the maximum allowed by the configuration of the RPR
reactor. The Reynolds number wasestimated for each liquid height
[22] and a turbulent regime was used: 6105, 7105 and 7105
for 5cm, 10cm and 15cm liquid depth, respectively.
The central operating condition (5.5mg Fe/L and 10cm height)
was replicated five times to determine the experimental error.
Hydrogen peroxide concentration was added at the beginning of
the process in a concentration of 50mg/L in all cases to ensure
excess. As the liquid depth changes, so does the treated water vol-
ume in each case. To ensure similar mixing times the paddle wheel
speed waschangedaccording to thetreated volume. Theresult was
a 2.5min mixing time for all cases.
UV radiationwas measured using a global UV radiometer (Delta
Ohm, LP UVA 02 AV) with a spectral response range from 327 to384nm, mounted on a horizontal platform,providing data in terms
of incidentUV radiation(W/m2).Also,theplantisequippedwithpH
and temperature probes. The variables were monitored on-line by
means of a LabJack USB/Ethernet data acquisition device connected
to a computer.Prior to thebeginning of theexperiments,the reactor
was covered and pH was adjusted to 2.80.05 with sulphuric acid.
A recirculation time of 5 min was allowed for homogenisation after
the addition of the pesticide mixture and iron salt, corresponding
to twice the mixing time in the photoreactor. Then the reactor was
uncoveredand hydrogenperoxidewas added, starting thereaction.
The reactor was continuously mixed during the experiments with
the paddle wheel. The experiments were always run at noon (from
12 to 13.30 p.m.), when solar irradiance was practically constant.
The average UV irradiance was 153W/m2. Average temperaturewas 282 C.
Both ACTM and TBZ are commonly used in citrus crops which
predominate in the Mediterranean agriculture (e.g. lemon, orange
trees) [30,31]. ACTM is a neonicotinoid insecticide and it has been
reported to be more resistant to oxidation than other pollutants
typically found in WWTP effluents [15,32]. TBZ is a widely used
benzimidazole fungicide. Thus, ACTM and TBZ serve the purpose of
model pollutants.
To study the effect of iron concentration and liquid depth, tap
water was used as matrix. The main properties of tap water are
presented in Table 1. Dissolved organic carbon (DOC) due to the
tap water was negligible. The small concentration of commercial
ACTM and TBZ (100g/L each) did not result in significant DOC
concentration either (less than 1 mg DOC/L).
Table 1
Tap water properties.
Parameter Concentration (mg/L)
Sulfate 29.5
Chloride 206.1
pH 7.9
Conductivity 0.85 mS/cm
To confirm the best operating conditions obtained in tapwater, experiments were carried out in simulated secondary
effluent from an urban WWTP used in previous works [15].
The constituents of the simulated secondary effluent were
CaSO42H2O (60 mg/L), MgSO4 (60mg/L), KCl (4mg/L), (NH4)2SO4(23.6 mg/L), K2HPO4 (7.0mg/L), NaHCO3 (96mg/L), beef extract
(1.8mg/L), peptone (2.7mg/L), humic salts (4.2mg/L), sodium
lignin sulfonate(2.4 mg/L), sodium lauryle sulphate (0.9mg/L),aca-
cia gum powder (4.7mg/L), and Arabic acid (5.0mg/L) [33]. The
dissolved organic carbon, DOC, of the initial water was 14mg/L.
2.3. Determination of the optical thickness
Regarding the absorption of the incident radiation, the ferric
iron species in solution are dominant for UV-light absorption ashydrogen peroxide and ferrous iron do not absorb any radiation
over 300 nm [21]. Absorption of ACTM, TBZ and generated inter-
mediates was checked and found negligible at the concentration
used in the experiments.
The absorption spectra of ferric iron in tap water were obtained
at different iron concentrations and making use of solar power
emission spectrum the spectral-averaged specific absorption coef-
ficient kA(mM1 m1) of solution species was determined, Eq. (4):
kA =
maxmin
Id
maxmin
Id(4)
where I is the solar power at the corresponding wavelength and
is the specific absorption coefficient of the solution at the cor-responding wavelength (mM1 m1). The wavelength limits in
Eq. (4) were those corresponding to radiometer spectral response
(327384nm). The specific absorption coefficient for ferric iron
species at pH 2.8 in tap water was 46mM1 m1.
The optical thickness, , was calculated as follows:
= kA CFe D (5)
where CFeis the iron concentration (mM) and D is the liquid depth
(m).
2.4. Chemical analysis
The sample volume was 10mL. All samples were immediately
filtered (nylon filters from Millipore with pores of 0.20m-diameter) and the filter was washed with 1 mLof acetonitrile and
mixed with the filtered water sample. This is because acetoni-
trile acts as an HO scavenger, stopping the reaction [34], and also
sweeps out any trace of pollutant that may have been retained by
the filter and avoid any possible adsorption.
Hydrogen peroxide was measured by a colorimetric method
using ammonium metavanadate, measuring the absorbance at
450nm [35]. The concentration of iron was determined accord-
ing to the o-phenantroline standardised procedure (ISO 6332) and
the red complex formed was determined spectrophotometrically
at 510 nm. DOC determinations were carried out in a Shimadzu-
V CPH TOC analyser. Anion concentrations were determined using
ion chromatography (Metrohm 881 Compact IC pro). The column
was an anionic MetroSep Supp 7 column (250/4.0mm5m) from
-
8/9/2019 artculo ambientaal
4/8
I. Carra et al. / Journal of HazardousMaterials 279 (2014) 322329 325
Metrohm. The eluent used was a solution of 3.6 mM Na2CO3 and
the flow rate was 0.8 mL/min.
ACTM and TBZ concentrations were determined by means of
liquid chromatography (UPLC Agilent 1200 Series equipped with
a column oven, degasser, autosampler and diode array detec-
tor) with a reversed-phase column (Agilent XDB-C18). The mobile
phase consisted of a gradient mixture of acetonitrile and 1% (v/v)
formic acid in water. Retention times were 6.1 min for TBZ, 9.6
for ACTM. The detection wavelengths were 300nm for TBZ and
248nm for ACTM. The gradient used was initially set at 5% ace-
tonitrile, progressively increasing the concentration to 100% in a
12-min method. The limit of detection (LOD) was 2g/L for ACTMand 1g/L for TBZ.
3. Results and discussion
3.1. Effect of liquid depth and iron concentration on pesticide
removal
In this work the solar photo-Fenton process was applied as
tertiary treatment, focusing on the effects of liquid depth and
iron concentration in the RPR operation. The degradation profilesobtained for the commercial pesticide mixture during the photo-
Fenton process are shown in Figs.2 and 3. The experimental error,
obtained from five replicates of the central operating condition
(5.5mg Fe/L10 cm liquidheight) waslowerthan 5% forACTM, TBZ
and hydrogen peroxide concentrations.
Either for ACTM or TBZ, two oxidation steps were clearly
detected, regardless of the liquid depth. The first step was always
marked by high and fast oxidation of the compounds due to the
initial reaction of Fe2+ with hydrogen peroxide (Eq. (1)) (Fenton
effect). It is rather fast, directly proportional to Fe2+ concentration
andgenerates a great amount of hydroxylradicals[36]. In said reac-
tion, Fe2+ is oxidised. On the second reaction step, Fe3+ is reduced
(Eq. (2)), establishing a continuous iron redox cycle (Eqs. (1) and
(2)). In this step, degradation is progressive, not as fast as in thefirst step because the ferric iron reduction is rate limiting.
Of the two compounds, ACTM presented slower degradation
rate than TBZ. As the most persistent compound of the mixture,
ACTMwas theone which gavefurtherinsight intothe results.Fig.2a
illustrates ACTM oxidation with 1 mg Fe/L for all liquid depths (5,
10 and 15cm). The first oxidation step, previously described, gave
rise to 19% removal. As this step is dependent on iron concentra-
tion, it was the same for all liquid depths. The second oxidation
step fitted an exponential decrease with similar degradation rates
for the three liquid depths. In all cases approximately 75% ACTM
removal was measured after 90min of solar photo-Fenton.
For 5.5mg Fe/L (Fig. 2b) the first oxidation due to Eq. (1) is
more significant as there was more initial Fe2+, reaching54% ACTM
removal in 2.5 min. In addition, there was a significant increase inthe process rate and complete removal was achieved in 40min for
all liquid depths with solar photo-Fenton. This short reaction time
is animportant factas it is one of the factors which affects costs the
most [11]. As observed with 1 mg Fe/L, the profiles were analogous
for the three liquid depths. This is also a significant effect. When
the liquid depth was 5cm, the treated volume was 120L. When
the liquid depth was increased to 10cm and 15cm, the treated
volumes were 240 and 360 L, respectively. So, the number of iron
ions present that needed to be photoactivated in the system was 2
and 3 times greater and so was the number of pesticide molecules.
However, the photons reaching the system remain the same as the
photoreactor surface did not change. Even so, the oxidation rate
with solar photo-Fenton was the same, regardless of the volume.
This meant that all iron ions were photoactivated for the three
Fig. 2. ACTM degradation by solar photo-Fenton and Fenton with 1, 5.5 and 10mg
Fe/L(243 WUV/m2 and 282 C).
liquid depths and the concentration of hydroxyl radicals generated
was similar.
When 10mg Fe/Lwas used(Fig.2c), there was an increase in the
process rateas well. However,it wasnot linearly proportionalto the
increase in iron concentration. The first degradation step involved
69%ACTMremovalfor allliquid depths, incomparisonwiththe 54%
achieved with 5.5mg Fe/L. This first degradation step wasthesame
for all liquid depthssince it is independent of irradiation.However,
in the second degradation step, there was a remarkable difference
with respect to the two lowest iron concentrations: the oxidation
-
8/9/2019 artculo ambientaal
5/8
326 I. Carra et al. / Journal of HazardousMaterials 279 (2014) 322329
Table 2
Kinetic constantsfor ACTMand H2O2.
Fe concentration (mg/L) Liquid height (cm) kACTM(min1) kH2O2 (mMmin
1)
Mean Standard deviation Mean Standard deviation
1 5, 10 and 15 0.02 0.002 0.003 0.0003
5.5 5, 10 and 15 0.08 0.004 0.012 0.0008
10 10 and 15 0.08 0.003 0.013 0.0009
10 5 0.13 0.021
of ACTM was faster in 5c m than in 10c m or 15c m liquid depth.
Indeed, complete removal time was 20min in 5cm liquid depth
and 40min in the other two.
This can be explained as follows, taking into account that the
amount of photons reaching the surface is the same for all liquid
depths but not the amountof iron ions: in 5 cmdepth with10 mg/L
of Fe there are 1.31022 iron ions in 120L which need certain
amount of photons to be photoactivated. When the treated volume
is increased to 240L or 360L, the number of iron ions is 2.61022
or 3.91022, respectively, but the amount of photons reaching the
system remains the same. Another approach to study this effect is
the optical thickness,which was calculated according to section 2.3
for every iron concentration and liquid depth. The maximum opti-cal thickness for 1 mg Fe/L was 0.12, and for 5 mg Fe/L, it was 0.68.
An optical thickness of 1 means that 90% of the photons entering
the reactor are absorbed. Therefore, there were enough photons
for both iron concentrations. Thus, for 1 and 5.5mg Fe/L all iron
ions were photoactivated for the three different depths as shown
in Fig.2a andb. Althoughthe highest optical thicknesswas obtained
for10mg/L(itrangedfrom0.41to1.24),solarradiationstillreached
the bottomof the reactor. However, with 10 and15 cm liquiddepth
theprocesscould become photo-limited. Nonetheless, these optical
thickness values are below the optimal range reported for photo-
catalytical reactors (1.83.4), pointing out that liquid depth could
still be increased keeping low iron concentration [37].
Fig.3 shows TBZdegradationprofilesfor 1 mg Fe/L and thethree
liquid depths. As previously mentioned, it was oxidised faster thanACTM and difficult to evaluate any effect at concentration >1mg
Fe/L. For 5.5 and 10mg Fe/L degradation was so fast it could not
be tracked. Indeed, for 5.5mg Fe/L complete removal was achieved
in 5min; while for 10mg Fe/L, the first degradation step (Fenton
effect) was already enough to completely remove all TBZ. This is
likely due to differences between the reactivity of hydroxyl radicals
towards ACTM and TBZ (hydroxyl radical is more reactive towards
Fig. 3. TBZ degradation by solar photo-Fenton and Fenton with 1 m g Fe/L
(24WUV/m2 and 282 C).
TBZ than ACTM). This is important since if only TBZ had been used
the effect of photo-limitation would not have been detected. The
first degradation step for 1mg Fe/L by Reaction 1 was more sig-
nificant as TBZ is likely more reactive towards hydroxyl radicals
than ACTM; andthe secondoxidation step also follows a fast expo-
nential decrease. Nevertheless, the profiles tendency proved to be
analogous to ACTM in the same conditions: the degradation rate
was similar for the three treated volumes. The discussion of TBZ
degradation follows the explanation given for ACTM above.
In addition to the photo-Fenton tests, the Fenton process was
alsocarriedoutasblank(Figs.2and3). The Fenton process is mainly
dependenton theconcentrationof iron andthe liquiddepth is nota
variable in this case. Additionally, the reduction of Fe3+ takes placethrough Eq. (3) instead of Eq. (2). As Eq. (3) is very slow [38], so the
most significant degradation occurred in the first degradation step,
which also happened in solar photo-Fenton. In no case was com-
plete ACTM removal accomplished in 90min, but high percentage
was obtained with 10mg Fe/L, 90%. This means the Fenton effect is
rather important in micropollutant removal only if high iron con-
centration is used. As a result, a combination of solar photo-Fenton
and Fenton (for cloudy days and nights) could be made to operate
continuously. This is essential for the commercial development of
this technology: extensive, less costly reactors which can operate
in continuous mode.
Aside from micropollutant concentration, hydrogen peroxide
consumption is crucial to corroborate the effects observed. In this
case, the reactant concentration was in light excess, 50mg/L, toensure that the micropollutant oxidation was not conditioned by
lackof hydrogenperoxide. Theevolution of hydrogenperoxide con-
centration with time is shown in Fig. 4. At first glance it can be
appreciated that the effects observed in ACTM degradation were
reflected in H2O2 concentration.
The factthat ACTMandH2O2profiles matched is especiallyclear
for10mg Fe/L, whereprofiles forthe 5-cm liquiddepth were differ-
entwithrespectto10cmand15cm(Fig.4c). H2O2 consumptionfor
different liquid depths with 10mg Fe/L corroborates the idea that
not all iron ions are photoactivated for 10-cm and 15-cm depth.
With 1 and 5.5mg Fe/L the degradation of H2O2 was similar
for all liquid depths (Fig. 4a and b). At the end of the test, 10%
H2O2 was still in the system for 5.5 m g Fe/L. When 1mg Fe/L
was used, only 30% H2O2 was consumed. This is consistent sinceH2O2 consumption rate is proportional to the concentration of
catalyst.
These results show the efficiency of the RPRs as extensive sys-
tems for micropollutant removal. A kinetic analysis was also made
to compare the value of the constants. For the calculation of the
kinetic constants, the first degradation step (Fenton) was omitted
since it was mainly a result of the first ferrous iron oxidation, as
described in Eq. (1), yielding a great amount of HO. It isin the sec-
ond degradation stage (photo-Fenton) whenthe Fe redoxcycle was
established as iron reductionis theslowestreaction inthe cycle and
is seriously affected by radiation absorption and, therefore, liquid
depth [15].
ACTM and TBZ profiles adjusted an exponentially decreasing
function, following a pseudo-first order degradation. ACTM
-
8/9/2019 artculo ambientaal
6/8
I. Carra et al. / Journal of HazardousMaterials 279 (2014) 322329 327
Fig. 4. Hydrogen peroxide concentration profiles during pesticide degradation by
solar photo-Fentonand Fentonwith 1, 5.5 and 10mg Fe/L.
pseudo-first order kinetic constants were calculated as well after
the first degradation stage and included in Table 2. Hydrogen per-
oxide profiles adjusted a linear decrease after the first degradation
stage, so pseudo-zero order kinetic constants were calculated
(Table 2). As kinetic constants for TBZ could not be obtained for
5.5 and 10mg Fe/L due to fast degradation, only ACTM constants
are presented. Since the degradation rate for 5, 10 and 15cm liq-
uid depth was the same for 1 and 5.5mg Fe/L, a mean value was
calculated. Standard deviation of ACTM and H2O2 constants were
Fig. 5. ACTM degradation and hydrogen peroxide consumption in simulated sec-
ondary effluentby solarphoto-Fentonin 15 cm liquid-depth-RPR with5.5 and10 mg
Fe/L, and in 5cm diameter-CPC with 5.5mg Fe/L.
included. For 10mg Fe/L and 5 cm, there was only one experiment,
so the kinetic values were not averaged.It could be seen that either for ACTM and H2O2 an increase in
catalyst concentration from 1 to 5.5 mg/L raised the kinetic con-
stant values four times: from 0.02min1 to 0.08min1 in the case
of ACTM; and from 0.003 mMmin1 to 0.012 mMmin1 for H2O2.
However, when the catalyst concentration was increased to 10mg
Fe/L, the kinetic constants were over 1.5 times greater only for
5 cm liquid depth (0.13 min1 and 0.021mM min1 for ACTM and
H2O2, respectively); while at the higher liquid depths the constants
remainedpractically the samethan for 5.5 mg Fe/L.This contributes
to the explanation given above that there was excess of catalyst for
10mg Fe/L at 10 and 15cm liquiddepth. Therefore, with the fastest
operating conditions (10 mg Fe/L and 5cm liquid depth) 120L of
water were treated in 20min. On the contrary, using 5.5mg Fe/L
with 10cm depth, 240L of water were treated in 40min and 360 Lwith 15cm liquid depth. As a result, the best operating condition
was 5.5 mg/L of Fe concentration and 15cm liquid depth.
3.2. Micropollutant removal in simulated secondary effluent
In simulated secondary effluent, the RPR was operated at the
highest liquid depth, 15cm, and two iron concentrations, 5.5 and
10mg Fe/L. Thefirst as the best operatingcondition obtained in tap
water and the second, to check if the use of a different matrix
with organic matter (14 mg/L DOC) could have an effect on the
process, for example, decreasing reaction rate as DOC scavenges
HO or augmenting water light absorption. In bothcases, increasing
Fe concentration would produce a clear effect increasing reaction
rate.Additionally, for comparison purposes, the same pesticide mix-
ture was degraded in a CPC photoreactor of 5 cm diameter, 0.48m2
collector area and 7L total volume, with 5.5mg/L of iron. More
CPC details and operation procedure are described elsewhere [39].
ACTM and hydrogen peroxide concentrations are shown in Fig. 5.
TBZ concentration is not shown as its degradation was too fast (it
was removed in less than 5 min).
Inthe RPR, ACTM as well as hydrogenperoxide degradationpro-
files were analogous for both iron concentrations, validating the
effects observed in tap water and excluding a detrimental effect
provoked by scavengers of HO or light absorption. Nevertheless
the acetamiprid degradation kinetic constantwas 0.01min1 inthe
secondaryeffluent;while theconstant intap water was0.08min1.
This is dueto thedifference inorganicmatterandsalts inbothwater
-
8/9/2019 artculo ambientaal
7/8
http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0155http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0150http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0145http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0140http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0135http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0130http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0125http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0120http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0115http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0110http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0105http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0100http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0095http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0090http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0080http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0075http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0070http://www.psa.es/webeng/projects/cadox/index.phphttp://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0060http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0055http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0050http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0045http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0040http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0035http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0030http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0025http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0020http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0015http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0010http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0005 -
8/9/2019 artculo ambientaal
8/8
I. Carra et al. / Journal of HazardousMaterials 279 (2014) 322329 329
[32] J. Gomis, A. Bianco Prevot, E. Montoneri, M.C. Gonzlez, A.M. Amat, D.O. Mr-tire, A. Arques, L. Carlos, Waste sourced bio-based substances for solar-drivenwastewater remediation: photodegradation of emerging pollutants, Chem.Eng. J. 235 (2014) 236243.
[33] R. Zhang, S. Vigneswaran, H. Ngo, H. Nguyen, A submerged membrane hybridsystem coupled with magnetic ion exchange (MIEX) and flocculation inwastewater treatment, Desalination 216 (2007) 325333.
[34] S. Mitroka, S. Zimmeck, D. Troya,J.M. Tanko, Howsolvent modulateshydroxylradicalreactivity in hydrogen atom abstractions, J. Am. Chem. Soc. 132 (2010)20132907.
[35] R.F.P. Nogueira, M.C. Oliveira, W.C. Paterli ni, Simple and fast spec-
trophotometric determination of H2O2 in photo-Fenton reactions usingmetavanadate, Talanta 66 (2005) 8691.
[36] P.R. Gogate, A.B. Pandit, A review of imperative technologies for wastewatertreatmentII: hybrid methods, Adv. Environ. Res. 8 (2004) 553597.
[37] G. LiPuma, Modeling of thin-film slurry photocatalytic reactors affected byradiation scattering, Environ. Sci. Technol. 37 (2003) 57835791.
[38] K. Ikehata, M.G. El-Din, Aqueous pesticide degradation by hydrogen perox-ide/ultraviolet irradiation and Fenton-type advanced oxidation processes: areview, J. Environ. Eng. Sci. 5 (2006) 81135.
[39] I. Carra,E. Ortega-Gmez, L. Santos-Juanes, J.L. Casas Lpez,J.A. Snchez Prez,Cost analysis of different hydrogen peroxide supply strategies in the solar:photo-Fentonprocess, Chem. Eng. J. 224 (2013) 7581.
[40] S. Malato Rodrguez, J. Blanco Galvez, M.I. Maldonado Rubio, P. FernandezIbanez, D. Alarcon Padilla, M. Collares Pereira, J. Farinha Mendes, J. Correia deOliveira, Engineering of solar photocatalytic collectors, Sol. Energy 77 (2004)513524.
Further reading
[17] F.G. Acin Fernndez, J.M. Fernndez Sevilla, E. Molina Grima, Photobioreac-tors for the production of microalgae, Rev. Environ. Sci. Biotechnol. 12 (2013)131151.
http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0160http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0160http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0160http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0160http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0160http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0165http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0165http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0165http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0165http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0165http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0165http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0170http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0170http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0170http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0170http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0170http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0175http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0175http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0175http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0175http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0175http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0175http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0175http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0175http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0180http://refhub.elsevier.com/S0304-3894(14)00571-8/sbref0180http://refhub.