applications of supercritical fluids 2018...

APPLICATIONS OF SUPERCRITICAL FLUIDS 2018 CONFERENCE

SZUPERKRITIKUS OLDÓSZEREK ANALITIKAI ÉS MŰVELETI ALKALMAZÁSA KONFERENCIA

17 May, 2018.

MTA Technical Chemistry Scientific Committee

MTA Working Group of Chemical Unit Operations

and Equipment

BME Department of Chemical and Environmetal

Process Engineering

MKE Technical Chemistry Division

BUDAPEST, HUNGARY

ISBN 978-963-313-287-6

Edited by: Ildikó KMECZ

APPLICATIONS OF SUPERCRITICAL FLUIDS 17 May, 2018.

3

Organiser: Dr. Edit SZÉKELY

Associate Professor

BME Department of Chemical and Environmental

Process Engineering

Co-Organiser: Dr. Attila IMRE

Professor

BME Department of Energy Engineering

MTA Centre for Energy Research, Department of Thermohydraulics

Organising Committee: Dr. Ildikó KMECZ, Assistant Professor

Dr. Erika Mária VÁGI, Assistant Professor

Dániel DÉVÉNYI, Gábor GYÖRKE

Márton KŐRÖSI, László LŐRINCZ

PhD Students

János BÉRI András KEREKES

Brigitta BOHUS Enikő KINCSES

Benedek DUDÁS László KONDOR

Karolina DURUCSKÓ Márta KUBOVICS

Dóra FARKAS Ákos TÓTH

Attila HORVÁTH Gábor UNOKA

Zsolt HOVONYECZ Mihály ZSITVAI

Fanni JUHÁSZ

Conference venue: Budapest University of Technology and Economics

Main building (Building K), 1st level, room 95.

Budapest, Műegyetem rakpart 3.

Wi-Fi: SSID: visitor

WPA2 password: aegh9hoo4fev

APPLICATIONS OF SUPERCRITICAL FLUIDS 17 May, 2018

4

PROGRAM

8:30-9:00 Regisztráció / Registration

9:00-9:05 Megnyitó / Opening (E. Székely, chair of the conference)

Délelőtti 1. szekció / morning session 1. 9:05-10:35

Chair: Sabine Kareth (RUB, Bochum, Germany)

9:05-9:35 Kamarás K., Botka B., Klupp G., Füstös M.E., Tóháti H.M., Székely E.,

Chamberlain T.W., Khlobystov A.N.: Encapsulation of molecules into

carbon nanotubes under mild conditions using supercritical carbon

dioxide

9:35-9:50 Bajtai A., Lajkó Gy., Szatmári I., Fülöp F., Lindner W., Ilisz I., Péter A.:

Comparative study for the characterization of enantiorecognitions

obtained by supercritical fluid chromatography and high-performance

liquid chromatography

9:50-10:05 Kőrösi M., Béri J., Kareth S., Madarász J., Sohajda T., Székely E.:

Enantiomeric enrichment by gas antisolvent fractionation

10:05-10:20 Tóth Á., Lőrincz L., Kondor L., Szilágyi I.M., Madarász J., Sohajda T.,

Székely E.: Antisolvent fractionation based optical resolution with 2-

phenylglycinol and its carbamate

10:20-10:35 Végh K., Riethmüller E., Balogh Gy.T., Béni Sz., Kéry Á.: Newly identified

flavonoids in Tanacetum parthenium supercritical fluid extract and their

LC-MS/NMR profiling using blood-brain barrier permeability assay

10:35-11:00 Kávészünet / Coffee break

Délelőtti 2. szekció / morning session 2. 11:00-12:15

Chair: Monika Johannsen (TUHH, Hamburg-Harburg, Germany and BME)

11:00-11:30 Hofland G., Dévényi D., Bucalossi A., Akkermans C., Land G., Van der Veen

B.: Scale-up of vegetable and herbs drying using supercritical carbon

dioxide

11:30-11:45 Győri E., Varga A., Fábián I., Lázár I.: Comparison of ethanolic and

supercritical CO2 extraction of herbs and selective adsorption of their

aroma materials in functionalized silica aerogels

11:45-12:00 Vági E., Balázs M., Komoczi A., Kiss I., Tolmacsov P., Mihalovits M.,

Székely E.: Cannabinoids enriched extracts from industrial hemp

residues

12:00-12:15 Kmecz I., Varga Zs., Szécsényi Á., Amairi V., Székely E.: Coupled

enzymatic resolution and product fractionation with supercritical carbon

dioxide

12:15-13:30 Ebédszünet / Lunch break

PROGRAM

5

13:30-14:00 Deiters U.K.: Modelling supercritical phase equilibria with equations of

state: problems and pitfalls

14:00-14:15 Imre A.R., Györke G., Katona A., Velmovszki D.: Anomalous properties of

some fluids in their pseudo-critical (widom) region

14:15-14:30 Roskosz M., Kareth S., Petermann M.: Crystal formation of metal-organic

coordination complexes by gas antisolvent crystallization

14:30-15:00 Kávészünet, beszélgetés a kiállítókkal, poszterek megtekintése /

Coffee break, informal discussion with exhibitors and discussion of the

posters

Délutáni 2. szekció / afternoon session 2. 15:00-16:30

Chair: Attila Imre (BME GPK, MTA EK)

15:00-15:30 Székely E., Tukacs J.M., Takács M., Auer R., Oláh D.F., Lengyel I., Mika

L.T.: Bio-oil generation from wheat straw by hydrothermal liquefaction

15:30-15:45 Fózer D., Sztancs G., Kiss B., Tóth A.J., Németh Á., Nagy T., Mizsey P.:

Hydrothermal carbonization of Chlorella vulgaris for upgrading the

yields of hydrothermal gasification

15:45-16:00 Horváth Á.: Investigation of corrosion resistance in supercritical water

16:00-16:15 Szabó Zs., Hegyfalvi Cs., Székely E., Falus Gy.: Dissolution and cation

exchange of Na-montmorillonite in dissolved scCO2 – implications for

caprock behavior in CO2 geological storage

16:15-16:30 Györke G., Imre A.R.: Potential phase transitions during loss of coolant

accidents in the supercritical water loops of various generation IV

reactor types

16:30-16:40 Zárszó / Closing remarks

Délutáni 1. szekció / afternoon session 1. 13:30-15:00

Chair: Ákos Horváth (MTA EK)


6

Poszterek / Posters

A poszterek a kávészünetekben és az ebédszünetben is megtekinthetőek lesznek, valamint

ezekben a szünetekben szeretnénk lehetőséget biztosítani a kiállítókkal és a poszterek

szerzőivel való kötetlen beszélgetésekre is. Kérjük ezért, hogy a posztereket a konferencia

megnyitásától a zárásáig hagyják fenn a táblákon.

Poster discussions are scheduled for the coffee and lunch breaks, which offers a possibility

of free discussions with the authors. We kindly ask the authors to place their posters before

the opening of the conference, and remove it only after the closing remarks.

András Cs.D., Mátyás L., Ráduly B., Salamon R.V., Székely E.: Increasing the prediction

power of Hansen solubility parameters in supercritical fluids

Dévényi D., Bohus B., Durucskó K., Székely E.: Differences in the composition of natural

oils obtained composition by conventional and scCO2 extraction technologies

Horváth A., Lőrincz L., Mihalovits M., Sohajda T., Komka K., Székely E.: Optical

resolution of ibuprofen by antisolvent precipitation of its diastereomeric salts

Kazmouz Y.M., László Sz., Rédei Cs., Bacskai I., Felinger A.: Surface excess isotherms of

organic modifier and carbon dioxide mixture in sub- or supercritical fluid

chromatography

Kubovics M., Al-Hamimi S., Huszár Gy., Turner C., Székely E.: Extracting and

analysing non-polar components of hawthorn berries

Rédei Cs., Felinger A.: Studying the competitive adsorption of alkylbenzenes and

methanol in supercritical fluid chromatography

Unoka G., Péter-Szabó B., Varga D., Gamse T., Székely E.: Supercritical fluid dyeing of

policarbonate with a disperse dye

SPONSORS

7

SPONSORS


8

ORAL PRESENTATIONS

ENCAPSULATION OF MOLECULES INTO CARBON NANOTUBES

UNDER MILD CONDITIONS USING SUPERCRITICAL CARBON

DIOXIDE

Kamarás K.1, Botka B.1, Klupp G.1, Füstös M.E.1, Tóháti H.M.1, Székely E.2,

Chamberlain T.W.3, Khlobystov A.N.3

1Wigner Research Centre for Physics, Institute for Solid State Physics and Optics,

Budapest, Hungary 2Budapest University of Technology and Economics, Department of Chemical and

Environmental Process Engineering, Budapest, Hungary 3University of Nottingham, School of Chemistry, Notthingham, United Kingdom

Carbon nanotubes can be used as „nanocontainers” to preserve small molecules in harsh

environments or as „nano-test-tubes” to perform chemical reactions in the confined space.

Encapsulation can proceed by sublimation at high temperature in vacuum, or from solution

in suitable solvents. Both these methods have shortcomings: high temperature induces

competing reactions and results in unwanted side products, and solvents enter the

nanocavities and are difficult to remove. Using the solution method with supercritical carbon

dioxide as solvent, however, creates close-to-ambient conditions and no side products, as

the solvent can be evaporated after the encapsulation reaction. We have successfully

encapsulated several molecules (fullerenes, polycyclic hydrocarbons and heterocyclic

compounds) into carbon nanotubes and performed chemical reactions in this environment.

Reaction parameters have to be optimized in each case. Products for possible application are

carbon nanoribbons and double-walled nanotubes with controlled dimensions.

References:

Botka B., Füstös M.E., Tóháti H.M., Németh K., Klupp G., Szekrényes Zs., Kocsis D.,

Utczás M., Székely E., Váczi T., Tarczay G., Hackl R., Chamberlain T.W., Khlobystov A.N.,

Kamarás K.: Small 10, 1369 (2014)

ORAL PRESENTATIONS

9

COMPARATIVE STUDY FOR THE CHARACTERIZATION OF

ENANTIORECOGNITIONS OBTAINED BY SUPERCRITICAL FLUID

CHROMATOGRAPHY AND HIGH-PERFORMANCE LIQUID

CHROMATOGRAPHY

Bajtai A.1, Lajkó Gy.1,2, Szatmári I.1, Fülöp F.2, Lindner W.3, Ilisz I.1, Péter A.1

1University of Szeged, Department of Inorganic and Analytical Chemistry, Szeged,

Hungary 2University of Szeged, Institute of Pharmaceutical Chemistry, Szeged, Hungary 3University of Vienna, Department of Analytical Chemistry, Vienna, Austria

The need for stereospecific chiral separations propelled the chromatography industry and

academia to develop plenty of novel chiral stationary phases (CSPs). Despite the large

number of chiral HPLC measurements, there is a shortage of comprehensive examination of

chiral HPLC and SFC. In this study similarities and differences between LC and SFC

methods are discussed on the basis of the obtained results.

Various CSPs including quinine- or quinidine-based zwitterionic and cellulose- or amylose-

based polysaccharides were applied in SFC and HPLC to investigate the chiral separation of

three basic and three ampholytic structurally related indole analogs. HPLC measurements

were carried out in polar ionic (PI) mode on the two zwitterionic CSPs and normal phase

(NP) mode on seven polysaccharide CSPs. In SFC mode the effects of the content and

natures of alcohol modifier, the counter-ion concentration and the structures of the analytes,

while in the NP-LC mode, the effects of the composition of the bulk solvent and the natures

of the alcohol and amine additives were investigated. The separations of the stereoisomers

were optimized in both chromatographic modes.

The effect of column temperature on the separation was also studied to provide results to

gain deeper understanding of the complex thermodynamic processes taking part in the

enantiorecognitions. Thermodynamic parameters were calculated applying van't Hoff plots

and the results showed that on the polysaccharide-based columns in NP-LC mode

enthalpically-, whereas in SFC mode both enthalpically- and entropically-driven enantiomer

separations were dominant.

The ampholyte compounds were unretained on all studied polysaccharide-based CSPs in

NP-LC, however, these analytes were successfully separated by SFC, demonstrating not

only an improved chromatographic performance but also a different suitability by the

application of SFC.


10

ENANTIOMERIC ENRICHMENT BY GAS ANTISOLVENT

FRACTIONATION

Kőrösi M.1, Béri J.1, Madarász J.2, Sohajda T.3, Hanu A.4, Kareth S.4, Székely E.1

1Budapest University of Technology and Economics, Department of Chemical and

Environmental Process Engineering, Budapest, Hungary 2Budapest University of Technology and Economics, Department of Inorganic and

Analytical Chemistry, Budapest, Hungary 3Cyclolab Cyclodextrin Research and Development Ltd., Budapest, Hungary 4Ruhr-University Bochum, Chair of Process Technology, Bochum, Germany

The application of supercritical carbon dioxide in separation processes is beneficial where

high purity and low pollutant levels are necessary. Besides its low critical point allowing

mild process conditions its application can also help in obtaining special products (e.g.

antisolvent processes). Although antisolvent precipitation and fractionation processes have

not found wide industrial application yet, they are promising methods to produce particulate

materials with a high added value. In the batch-type gas antisolvent fractionation (GASF)

the polarity of an organic solution is reduced by adding carbon dioxide. By carefully setting

the operational parameters, selective precipitation and subsequent extraction can be carried

out.

Enantiomerically pure compounds are required in the pharmaceutical and cosmetic

industries. Recrystallisation of scalemic mixtures or diastereomeric salts is a simple and

straightforward way to obtain such substances. In this study, both cases are presented on the

scalemic mixtures of 3-chloromandelic acid and the diastereomeric mixtures of 1-

phenylethanammonium-4-chloromandelate salts. GASF experiments were carried out in a

laboratory autoclave at 16 MPa and 40 °C with 1 hour equilibration time. 75:1 carbon

dioxide to acetonitrile molar ratio was applied in case of the enantiomeric mixtures and 6:1

and 9:1 carbon dioxide to methanol molar ratios were set in case of the diastereomeric salts.

Purification results were compared to the atmospheric melting phase diagrams of the

diastereomers and enantiomers. The results of the diastereomeric salt formation show that

the eutectic composition and the composition limiting the enantiomeric purification

correlate. The quantity of the co-solvent has an influence on the product purity. The same

correlation could be observed in case of the scalemic mixtures of 3-chloromandelic acid.

The melting phase diagram of the latter was also recorded at different pressures in the range

of the operational pressure of the GASF process.

This research was funded by OTKA (grant number K108979) and supported by the DAAD

(personal reference number 91676878).

ORAL PRESENTATIONS

11

ANTISOLVENT FRACTIONATION BASED OPTICAL RESOLUTION

WITH 2-PHENYLGLYCINOL AND ITS CARBAMATE

Tóth Á.1, Lőrincz L.1, Hovonyecz Zs. 1, Kondor L.1, Sohajda T.2, Székely E.1


Environmental Process Engineering, Budapest, Hungary 2Cyclolab Cyclodextrin Research and Development Ltd., Budapest, Hungary

There is a growing demand for eco-friendly technologies and substances in the modern

chemical and pharmaceutical industry. High productivity processes are often

environmentally friendly as well, this is one of the reason flow techniques gained

considerable interest in the pharma field as well. Supercritical solvents are also considered

as low environmental impact solvents, especially carbon dioxide.

Chiral resolution is the general term applied to the separation of enantiomers, which is an

important process in today’s pharmaceutical industry, but it is growing more and more

significant in the modern pesticide industry as well.

In this study, the chiral resolution of ibuprofen model compound by gas antisolvent and in

situ methods were investigated with (S)-2-phenylglycinol as the resolving agent. The

resolving agent was applied in half molar equivalent.

In carbon dioxide only the resolving agent readily reacts with the solvent forming a self-

carbamate salt. For the first time in the literature we demonstrated, that such a salt acts as an

efficient resolving agent and its reaction with ibuprofen is faster than the phenyglycinol

itself.

The effect of pressure, temperature, salt concentration, the carbon dioxide-solvent ratio, the

reaction time, the amount of washing fluid were investigated by a batch gas antisolvent

method, which was transferred to a semicontinuous antisolvent equipment as well. The

temperature did not affect raffinate selectivity, while the higher pressures had a decreasing

effect on the same value. The amount of washing fluid used in the experiments and reaction

times beyond one hour did not affect raffinate selectivity, while increasing the salt

concentration or the carbon dioxide-solvent ratio had positive effect on separation efficiency

until a critical raffinate selectivity value was reached. Further increase in the values of these

two parameters had no further effect. At an optimal parameter set the precipitated salt has

60-68% diastereomeric excess and the selectivity is appr. 0.4. By the repeated resolution of

non-racemic ibuprofen 0.99 diastereomeric purity can be reached in three steps at relatively

high raffinate yields.

We highly appreciate the help of Prof. János Madarász in the analysis of the solid phases.

This work is related to the National Research, Development and Innovation Fund of Hungary

in the frame of FIEK_16-1- 2016-0007 (Higher Education and Industrial Cooperation

Center), K108979 projects.

References:

Larsen R.D., Corley E.G., Davis P., Reider P.J., Grabowski E.J.J.: J. Am. Chem. Soc., 111,

7650 (1989)


12

NEWLY IDENTIFIED FLAVONOIDS IN TANACETUM PARTHENIUM

SUPERCRITICAL FLUID EXTRACT AND THEIR LC-MS/NMR

PROFILING USING BLOOD-BRAIN BARRIER PERMEABILITY ASSAY

Végh K.1, Riethmüller E.1, Balogh Gy.T.2, Béni Sz.1, Kéry Á.1

1Semmelweis University, Department of Pharmacognosy, Budapest, Hungary 2Gedeon Richter Plc., Compound Profiling Laboratory, Budapest, Hungary

Feverfew (Tanacetum parthenium L.) as a perennial herb has been known for centuries due

to its medicinal properties. In the recent research a supercritical CO2 extraction was carried

out at different pressures, temperatures and co-solvent contents in order to study the

extraction yield and the parthenolide recovery of the extracts. Leaves collected before and

during flowering and flower heads were investigated. The critical values of parthenolide

content were found to be 7% EtOH, 22 MPa and 64°C in case of all three samples. The

presence of methylated flavonoids beside parthenolide and other sesquiterpene lactones were

indicated by preliminary LC-MS analyses.

Specific Parallel Artificial Membrane Permeability Assay (PAMPA) was applied to identify

the components, including parthenolide and methylathed flavonoids, capable to cross the

Blood-Brain Barrier (BBB). Three lipophilic flavonoids were detected on the acceptor side,

that were isolated (Prep-HPLC) and identified as sudachitin, aceronin and nevadensin (LC-

MS/MS, NMR). These flavonoids were also characterized individually by PAMPA-BBB

model. The presence of sudachitin and nevadensin was proven in the Asteraceae family, but

neither of the three flavonoids were reported before in Tanacetum parthenium L.

References:

Végh K., Riethmüller E., Hosszú L., Darcsi A., Müller J., Alberti Á., Tóth A., Béni Sz.,

Könczöl Á., Balogh Gy.T., Kéry Á.: Journal of Pharmaceutical and Biomedical Analysis

149, 488-493 (2018)

Végh K., Alberti Á., Riethmüller E., Tóth A., Béni Sz., Kéry Á.: The Journal of Supercritical

Fluids 95, 84-91 (2014)

Könczöl Á., Müller J., Földes E., Béni Z., Végh K., Kéry Á., Balogh Gy.T.: Journal of

Natural Products 76, 655-663 (2013)

ORAL PRESENTATIONS

13

SCALE-UP OF VEGETABLE AND HERBS DRYING USING

SUPERCRITICAL CARBON DIOXIDE

Hofland G.1, Dévényi D.1, Bucalossi A.1, Akkermans C.1, Land G.2, Van der Veen B.2

1FeyeCon Development & Implementation b.v., Weesp, the Netherlands 2VNK Herbs, Biddinghuizen, the Netherlands

Drying processes are often used to increase the shelf-life of food products and are frequently

performed by freeze-drying, hot-air drying, or others thermal drying techniques. Drying of

plant materials implies both physical and chemical changes which compromise the overall

quality of the product. Depending on the method used, colour loss, flavour loss, loss of

structure and shrinkage of the product occurs. Drying solid food products with supercritical-

CO2 (scCO2) has the potential to reduce the energy consumption and obtain a better-

preserved structure.

Drying using CO2 as a drying agent was investigated at pilot scale of ca. 10 kg input. Dry

CO2 was recirculated over stacked beds of the vegetables or herbs, after which CO2

regenerated by means of drying over a solid sorption medium. In this manner, the drying and

regeneration process was operated at almost the same pressure level and recompression

/pumping costs were minimized.

Fig. 1. Ten litre bucket of CO2 dried parsley

Drying was performed on vegetables such as bell pepper and carrot, as well as herbs such as

parsley and coriander. Influence of scaling factors such as location in the drying vessel and

processing time were analysed on the basis of the level of dryness and product quality

parameters such as colour, shape and shrinkage. Further, comparisons with labscale and

bench scale operation, at 150 g and 1 kg respectively were made to assess the influence of

scale. Finally, product safety was established by assessing the microbial inactivation.

Acknowledgment: EU HORIZON 2020 Project Future Food (Grant Agreement No. 635759)


14

COMPARISON OF ETHANOLIC AND SUPERCRITICAL CO2

EXTRACTION OF HERBS AND SELECTIVE ADSORPTION OF THEIR

AROMA MATERIALS IN FUNCTIONALIZED SILICA AEROGELS

Győri E.1, Varga A.1, Fábián I.1, Lázár I.1

1University of Debrecen, Department of Inorganic and Analytical Chemistry,

Debrecen, Hungary

e-mail:[email protected]

Medicinal agents originated from plants have been used even in ancient Egypt and several

herbs are used for the same reason since then. Nowadays the cosmetic and the modern

pharmaceutical industry use increasing quantities of herbs’ aroma materials. Their positive

and the side effects are both well known. Furthermore, it is more cost-effective to produce

medicine from herbs than the synthesis of new medicinal agent. The isolation of the natural

agent, however, can be expensive, since, besides the extraction, the purification and

enrichment can be problematic in case of a complex extract.

There are several methods for extraction of the aromatic compounds from herbs, for

example, the hydrodistillation, cold, pressing or the organic solvent extraction. With the

increasing need for the aromatic compounds, the development of more efficient and

environmentally friendly processes come more and more into view. The supercritical fluid

extraction can be an alternative clean technique. The most frequently used solvent is the

supercritical carbon dioxide, since the critical point of CO2 can be reached easily, does not

modify the heat-sensitive compounds and chemically inert. In addition, it is cheap, can be

removed from the extract without residue and reused as well as – because its polarity is

similar to that of the pentane – can extract lipophilic compounds too. [1]

In our research, five herbs were extracted with ethanol and supercritical CO2 then we studied

the adsorption of their aroma materials in silica aerogels. The aroma materials and drugs

were identified by the GC-MS-EI technique. According to our results, the SFE technique

was more efficient in most cases with regard to the number of extracted compounds.

Furthermore, while the ethanolic maceration took 7 days, the supercritical fluid extraction

lasted only 24 hours. Different surface polarity silica aerogels showed specific selectivities

for the components, and the aerogels proved to be an excellent adsorber even for the

components which were present in a fairly low concentration in the extracts.

References:

[1] Capuzzo A., Maffei M. E., Occhipinti A.: Molecules 18, 194- 238 (2013)

Acknowledgements: The work/publication is supported by the GINOP-2.3.2-15-2016-

00041 and the GINOP-2.2.1-15-2017-00068 project. The project is co-financed by the

European Union and the European Regional Development Fund.

ORAL PRESENTATIONS

15

CANNABINOIDS ENRICHED EXTRACTS FROM INDUSTRIAL HEMP

RESIDUE

Vági E.1, Balázs M.2, Komoczi A.2, Kiss I.2, Tolmacsov P.2, Mihalovits M.1,

Székely E.1


Environmental Process Engineering, Budapest, Hungary 2Bay Zoltán Nonprofit Ltd., for Applied Research, Division for Biotechnology,

Szeged, Hungary

Hemp (Cannabis sativa L.) is one of oldest cultivated annual crops meanwhile it can be also

considered as one of the most controversial plant in our society. Industrial hemp is cultivated

for products such as fibre for paper and textile, cellulose, hemp seed oil for food, cosmetics

and pharmaceutical industries. Recently research interest has been increased in

phytocannabinoids, which are associated with various medicinal and therapeutic properties

with no reported side effects. The phychotropic Δ-9-tetrahydrocannabinol (THC) is less than

0.2% in industrial cultivates therefore can be grown officially in many EU countries.

Harvesting and processing of hemp generates large amount of wastes containing substantial

amounts of bioactives such as: cannabidiol (CBD) which is the primary cannabinoids along

with cannabidiolic acid (CBDA), cannabinol (CBN), cannabigerol (CBG), and

cannabichromene (CBC).

The aim of this work was to optimize the extraction of cannabinoids from industrial hemp

waste using supercritical carbon dioxide extraction. A pilot plant 5 L high pressure extraction

vessel equipped with two separation vessels in series was used. The effects of extraction

pressure and temperature on the extraction yield were evaluated along with the effects of

pressure and temperature of separation vessels on the enrichment of cannabinoids were

studied. The effect of ethanol co-solvents added to the supercritical solvent was also

assessed. Six different samples from different sources were also compared. After

derivatization of the samples, the cannabinoids and the minor THCs were quantified by GC.

The extraction yields were between 1.05 – 9.24 g/100 g dry mass depending on the source

of hemp residue and on the parameters of extraction process. Increasing the pressure of

extraction (in the range of 250-450 bar and 45°C) the extraction yields increased, meanwhile

the yield of cannabinoids showed no significant increase. The pressure of the first separation

vessel had significant effect on the yields and on the enrichment of cannabinoids. For optimal

fractionation of cannabinoids from hemp essential oil the pressure of first separator was set

at 80 bar and 40°C, while if the first separator operated at 100 bar and 40°C a slight

separation among the cannabidiol and cannabidiolic acid was observed.

References:

Citti C., Braghirolli D., Vandelli M. A., Cannazza G.: J. Pharm. Biomed. Anal, 147, 565

(2018)

Rovetto L., Aieta N. V.: J. Supercrit. Fluids, 129, 6 (2017)

Kitryte V., Bagdonaite D., Venskutonis P. R.: Food Chem, article in press

(http://dx.doi.org/10.1016/j.foodchem.2017.09.080) (2017)

Attard T. M., Bainier C., Reinaud M., Lanoth A., McQueen-Mason G. R., Hunt A. J.: Ind.

Crops Prod. 112, 38 (2018)

http://dx.doi.org/10.1016/j.foodchem.2017.09.080


16

COUPLED ENZYMATIC RESOLUTION AND PRODUCT

FRACTIONATION WITH SUPERCRITICAL CARBON DIOXIDE

Kmecz I.1, Varga Zs.1, Szécsényi Á.1, Amairi V.1, Székely E.1


Environmental Process Engineering, Budapest, Hungary

The importance of the production of enantiopure compounds is attributed to the different

behavior of the enantiomers in a chiral environment. Enzymes are highly selective catalysts

to obtain pure enantiomers via the kinetic resolution of racemates. Enantiopure secondary

alcohols are useful intermediates for fine chemicals. Pure alcohol enantiomers can be

obtained by lipase catalyzed transesterification reaction. The typically applied esterification

agents are vinyl esters, especially the highly volatile vinyl acetate. Due to the wide substrate

specificity of commercial lipases, environmentally friendly and non-toxic synthetic glycerol

esters and natural oils might also be applied efficiently in the resolution of secondary

alcohols [1,2]. Lipases maintain their activities in organic and non-conventional solvents,

like supercritical carbon dioxide. Due to the tunable properties of scCO2, its application as a

solvent has a special advantage in product separation after the kinetic resolution [3].

In the presented work, kinetic resolution of 1-phenylethanol (PE) was investigated with

glycerol derivatives (glycerol triacetate (GTA), glycerol tributirate (GTB)) and corn germ

oil catalyzed by Novozyme 435 enzyme. Corn germ oil was obtained by supercritical fluid

extraction (p = 45 MPa, 50°C). Reactions in scCO2 were executed at the pressure of

10 and 20 MPa in the range of 40 – 60 °C. Atmospheric reference reactions were performed

in n-hexane and neat. Novozyme 435 enzyme catalyzed the conversion of the (R)-isomer of

the racemic PE substrate selectively with an equilibrium converson > 45% both in scCO2

and at ambient pressure in case of each esterification reagents. At high-pressure conditions,

phase equilibrium strongly depends on alkyl chain length of the glycerol ester. Using GTA

as acylation agent the reaction mixture is completely dissolved in scCO2 at 10 and 20 MPa,

but in case of corn germ oil the enzyme catalyzed reaction is performed in a corn germ oil –

scCO2 biphasic system up to 20 MPa. The biphasic system and the solubility differences

allowed to extract the esters and the remaining alcohol by SFE following the reaction.

Product fractionation was performed by sequential pressure drop.


in the frame of K108979 project.

References:

[1] Wolfson A., Atyya A., Dlugy C., Tavor D.: Bioprocess Biosyst. Eng. 33, 363-366

(2010)

[2] Wolfson A., Komyagina N., Dlugy C., Blumenfeld J.: Green Sustain. Chem. 1, 7-11

(2011)

[3] Paiva A., Vidinha P., Angelova M., Rebocho S., Barreiros S., Brunner G.: J. Supercrit.

Fluids 55, 963-970 (2011)

ORAL PRESENTATIONS

17

MODELING SUPERCRITICAL PHASE EQUILIBRIA WITH EQUATIONS

OF STATE: PROBLEMS AND PITFALLS

Deiters U.K.1

1University of Cologne, Institute of Physical Chemistry, Cologne, Germany

Nowadays there exist numerous processes involving supercritical fluid phases, from the

extraction of alkaloids, flavours or dyes from agricultural products, the processing (in

particular the micronisation) of pharmaceutical products, or the processing of natural gas.

Consequently, the thermodynamic modeling of such processes is important, and this field of

science has indeed been showing an impressive progress over the past decades.

Sometimes, however, there exist complications, and some of them are dicussed here:

the quality of solid-state thermodynamic data used for modeling supercritical

extractions,

density or entropy inversion,

appearance of unexpected phases, and the sensitivity of thermodynamic models to

this phenomenon.

For the latter point it is necessary to briefly review the classification of phase diagrams of

binary fluid mixtures, and then to discuss “global phase diagrams”, i. e., maps showing the

dependence of the phase diagram classes on the parameters of equations of state.

References:

Deiters U.K., Randzio S.L.: Fluid Phase Equilib. 260, 87 (2007)

Imre A.R., Quiñones-Cisneros S.E., Deiters U.K.: Ind. Eng. Chem. Res. 54, 6559 (2015)

Bolz A., Deiters U. K., Peters C. J., de Loos Th.W.: Pure Appl. Chem. 70, 2233 (1998)

Deiters U.K., Kraska T.: Fluid Phase Equilibria – Phenomenology and Computation,

Supercritical Fluid Science and Engineering (E. Kiran, ed.), vol. 2, Elsevier, Amsterdam

2012.


18

ANOMALOUS PROPERTIES OF SOME FLUIDS IN THEIR

PSEUDO-CRITICAL (WIDOM) REGION

Imre A.R.1,2,*, Györke G1, Katona A.1, Velmovszki D.1

1Budapest University of Technology and Economics, Department of Energy

Engineering, Budapest, Hungary 2MTA Centre for Energy Research, Department of Thermohydraulics, Budapest,

Hungary * [email protected], [email protected]

Upon normal boiling at a constant pressure, some relevant material properties (density, heat

capacities, compressibilities, etc.) change abruptly at the boiling point, giving a well-defined,

sharp border between liquid and fluid phases. Going above the critical pressure, similar

change of these properties can be seen upon heating (the phenomenon is often referred as

pseudo-boiling), but there are at least four relevant differences. First and second, although

one can see some characteristic change by changing the state from liquid-like to vapour-like,

the changes are smaller than for real boiling and it is not abrupt. For water at 23 MPa, density

drops to the half of its initial value, from 0.455 g/cm3 to 0.229 g/cm3 within a 4 K wide

temperature range (648 K to 652 K) [1]. The third point is, that while upon normal boiling,

all properties are changing simultaneously, in the pseudo-critical region their change can be

shifted, i.e. the fluid can show liquid-like isothermal compressibility, but vapour-like density

at a given temperature, because the compressibility changes only at higher temperature.

Lastly, upon pseudo-boiling, some of the material properties reach values which is neither

liquid-like, nor vapour-like, showing that the supercritical state is not “only” a transition

between liquid and vapour, but an own state with own, sometimes peculiar properties.

In our presentation, some overview will be given about the peculiarities of the pseudo-

critical region (including the meaning of liquid-like and vapour-like on molecular level),

with special emphasis on properties relevant for energy production and conversion [2]. Also,

the property-map of some materials (argon as a model fluid and methane, water and carbon

dioxide as fluids with special importance in energy engineering) will be presented.

References:

[1] Imre A.R., Deiters U.K., Kraska T., Tiselj I.: Nuclear Engineering & Design, 252, 179

(2012)

[2] Imre A.R., Ramboz C., Deiters U.K., Kraska T.: Environmental Earth Sciences, 73,

4373 (2015)

ORAL PRESENTATIONS

19

CRYSTAL FORMATION OF METAL-ORGANIC COORDINATION

COMPLEXES BY GAS ANTISOLVENT CRYSTALLIZATION

Roskosz M.1, Kareth S.1, Petermann M.1

1Ruhr-University Bochum, Chair of Particle Technology, Bochum, Germany

Crystallization and precipitation from solutions are responsible for more than 70 % of all

solid materials produced by the chemical industry. Operational conditions largely influence

the product characteristics such as crystal size, morphology and purity. Crystallization may

occur as the formation of solid particles from a vapor, as solidification from a liquid melt or

as the formation of solids from a solution. The major drawbacks of these methods are the

use of high amounts of organic solvent, high temperatures, very expensive washing steps

and residual solvent in the final product. The use of supercritical fluids is an alternative to

these conventional methods to eliminate or reduce these disadvantages. The gas antisolvent

(GAS) crystallization has been demonstrated to be an effective technique for the

micronization of various materials. In this process, a dense gas, commonly CO2, is used as

the antisolvent. [1,2]

The primary aim of this work was to determine the applicability of the GAS method for the

single crystal growth of metal-organic coordination complexes. In order to reveal the

chemical structure of the synthesized complexes of the crystals, it is necessary to use X-ray

single crystal structure analysis. The challenge lies in the production of large

monocrystalline crystals required for the X-ray diffractometer, with a minimum size of

100 μm. [3,4]

Therefore, we investigated the crystallization of various metal-organic coordination

complexes with the GAS method. For that, the complexes are dissolved in organic solvents

first and then precipitated by supercritical CO2 as antisolvent. For that case, CO2 has to be

miscible with the organic solvent at operating conditions, while the solute is insoluble in the

dense gas. Single crystals suitable for X-ray analysis could be obtained by the GAS method

in a few hours. In comparison, conventional crystallization methods are extremely time-

consuming (weeks to months).

References:

[1] Giulietti M. Seckler M.M., Derenzo S., Ré M.I., Cekinski E.: Braz. J. Chem. Eng. 18,

423 (2001)

[2] Knez Z., Knez Hrncic M., Skerget M.: Annu. Rev. Chem. Biomol. Eng. 6, 379 (2015)

[3] Li L.N., Sun F.X., Jia J.T., Borjigin T., Zhu G.S.: Cryst. Eng. Comm. 15, 4094 (2013)

[4] Rodrigues M.O., de Paula M.V., Wanderley K.A., Vasconcelos I.B., Alves S., Soares

T.A.: Int. J. Quantum Chem. 112, 3346 (2012)


20

BIO-OIL GENERATION FROM WHEAT STRAW BY

HYDROTHERMAL LIQUEFACTION

Székely E.1, Tukacs J.M.1, Takács M.2, Auer R.2, Oláh D.F.1, Lengyel I.1, Mika L.T.1


Environmental Process Engineering, Budapest, Hungary 2 MOL NyRt., Budapest, Hungary

The current and growing need for sustainable resources of energy and platform molecules

for the chemical industries facilitates research and development activities related to biomass

conversion. Hydrothermal liquefaction (HTL) could be one of the possibilities to produce

bio-oil, the processing of which might be possibly integrated in longer term into a standard

refinery for renewable fuel production. Major advantage of HTL compared to pyrolysis is

that in the latter case removal of water is required, while the solvent of HTL is pressurized

water. Consequently a biomass with high moisture content can readily be treated with HTL.

[1]

HTL is typically operated in the 250-350 °C temperature and 10-18 MPa pressure ranges,

which is subcritical, or near critical region of water. Typical composition of HTL bio-oil is

also more favorable than that of pyrolysis oil due to lower oxygen content. [2]

A semi-continuous experimental unit was developed to study the effects of process

parameters (pressure, temperature, average residence time, the presence of co-solvent i.e.

alcohol) on the bio-oil yield of wheat straw as well as a batch reactor setup for the catalyst

screening and testing of addition of hydrogen was installed. The preparative bio-oil yield

was conservatively defined as the ethyl acetate soluble fraction.

As high as 45 wt% of the dry weight of the wheat straw was obtained as bio-oil at optimized

parameter sets, with an elementary composition of 58–63% carbon, 5–8% hydrogen and 23–

28% oxygen. Total conversion (remaining solid <5%) was achieved with low gas yields

(<3%) but significant water soluble yields.

The research work was supported by VEKOP-2.1.1-15-2016-00028 project of the Széchenyi

2020 program.

References:

[1] Elliott, D.C. et al., Bioresource Technology, 178, pp.147–156. (2015) Available at:

http://dx.doi.org/10.1016/j.biortech.2014.09.132.

[2] Toor, S.S., Rosendahl, L. & Rudolf, A., Energy, 36(5), pp.2328–2342 (2011) Available

at: http://dx.doi.org/10.1016/j.energy.2011.03.013.

[3] Deniel, M. et al., Renewable and Sustainable Energy Reviews, 54, pp.1632–1652.

(2016) Available at: http://dx.doi.org/10.1016/j.rser.2015.10.017

ORAL PRESENTATIONS

21

HYDROTHERMAL CARBONIZATION OF CHLORELLA VULGARIS FOR

UPGRADING THE YIELDS OF HYDROTHERMAL GASIFICATION

Fozer D.1, Sztancs G.1, Kiss B.2, Toth A.J.1, Nemeth A.2, Nagy T.1, Mizsey P.1,3


Environmental Process Engineering, Budapest, Hungary 2Budapest University of Technology and Economics Department of Applied

Biotechnology and Food Science, Budapest, Hungary, 3University of Miskolc, Department of Fine Chemicals and Environmental

Technology, Miskolc, Hungary

Biochar (a.k.a. hydrochar) is a stable solid product derived from biomass which can be used

in number of areas (e.g., electricity and heat production, carbon sequestration, adsorbent,

catalyst production and soil amendment). The characteristics of the carbonized biomass

depend on process conditions and feedstocks. Hydrothermal treatment of biomass is a

promising downstream technology due to the moderate reaction conditions and the

unnecessity of pretreatment steps of the biomass. The examination of hydrothermal

carbonization on Chlorella vulgaris is carried out in order to produce energy dense solid

product and to investigate the produced hydrochar role in hydrothermal gasification process

as a heterogeneous catalyst.

Hydrothermal carbonization were performed based on 22 factorial design of experiment

where the investigated factors were the temperature (175-210°C) and pressure (1.5-4.5

MPa). The reaction time and algae load were the same in the experiments, 45 min and 15

wt.%, respectively. The volatile matter, fixed carbon and the ash content of hydrochar were

measured. The higher heating value, energy densification, fuel ratio and energetic recovery

efficiency of the produced hydrochar samples were determined.

Hydrothermal gasification measurements were carried out at 650°C and 30 MPa with 10

wt.% algae load and an average 120 sec residence time. It is found that hydrochar has effects

on the gasification properties, the total gas, hydrogen and methane yield.

References:

Wu K., Gao Y., Zhu G., Yuan Q., Chen Y., Cai M., Feng L.: J. Anal. Appl. Pyrolysis 127,

335-342 (2017)


22

INVESTIGATION OF CORROSION RESISTANCE IN SUPERCRITICAL

WATER

Horváth Á.1

1MTA Centre for Energy Research, Budapest, Hungary

Nuclear reactors operating at temperatures above 500 °C were already built in 1950s and

1960s for demonstration purposes. The interest was recently renewed within the frame of

the Generation IV reactors international forum. The supercritical-water-cooled reactor

(SCWR) concept offers a great potential in fuel economy, and simplification in the nuclear

system. The improvement is due to high thermal efficiency and plant simplification

supported by the unchanged phase of the coolant in the reactor.

The successful development of an innovative reactor design depends on the development of

materials with adequate mechanical properties, dimensional stability and resistance to

environmental attack.

Since supercritical water (water above 374 °C and 22.1 MPa) has never been used in

commercial nuclear power applications, there are numerous questions regarding potential

material problems that must be considered. In recent years extensive materials development

has taken place within the fossil power generation programs. However, this development

work was mainly focused on the mechanical strength at high temperatures and the oxidation

and corrosion aspects have not been investigated adequately. Corrosion in particular has

been identified as a critical problem because the temperature and the oxidative nature of

supercritical water increase the speed of corrosion.

An in-house made supercritical pressure autoclave was built in MTA EK to study the

corrosion resistance of some candidate cladding materials. In parallel to this activity, the

group also contributed to an international collaboration lead by KIT (Germany). Several

ideas on the adequate sample preparation and chemical composition were tested to find a

proper alloy with low oxidation rate.

At present, no single candidate alloy has been identified as the probable alloy for use as

either cladding or structural materials in SCW reactors. The different compositions and

surface preparation technologies were intensively investigated by the different collaborators

in the European projects HPLWR, GETMAT and SCWR-FQT between 2000 and 2014.

The paper gives an overview of the status of the SCWR concept and summarizes the main

findings of the different international projects on the oxidation rate in supercritical water.

ORAL PRESENTATIONS

23

DISSOLUTION AND CATION EXCHANGE OF NA-

MONTMORILLONITE IN DISSOLVED SCCO2 - IMPLICATIONS FOR

CAPROCK BEHAVIOR IN CO2 GEOLOGICAL STORAGE

Szabó Zs.1,2, Hegyfalvi Cs.3, Székely E.3, Falus Gy.1

1Mining and Geological Survey of Hungary, Department of Hydrogeology and

Geochemistry, Budapest, Hungary 2MTA Premium Postdoctorate Research Program, Office of Funded Research

Groups, Budapest, Hungary 3Budapest University of Technology and Economics, Department of Chemical and


One of the challenges of the present century is to limit the greenhouse gas emissions for the

mitigation of climate change which is possible for example by a transitional technology, CO2

geological storage. Clay minerals are considered to be responsible for the low permeability

and sealing capacity of caprocks sealing off stored CO2. This work aims to create a kinetic

geochemical model of Na-montmorillonite standard SWy-2 supported by solution and

mineral composition results from batch experiments. Such experimentally validated

numerical models are scarce. Several 70-hours experiments have been carried out at

atmospheric conditions, and with CO2 supercritical phase at 100 bar and 80 ⁰C. Solution

samples have been taken during and after experiments and their compositions were measured

by ICP-OES. The treated solid phase has been analyzed by XRD and ATR-FTIR and

compared to in-parallel measured references (dried SWy-2). Kinetic geochemical modelling

of the experimental conditions has been performed by PHREEQC. Experiments and models

show very fast reactions under the studied conditions and increased reactivity in presence of

scCO2. Solution composition results cannot be described by the change of the uncertain

reactive surface area of mineral phases. By considering the clay standard’s cation exchange

capacity divided proportionally among interlayer cations of Na-montmorillonite, the

measured variation can be described on an order of magnitude level. It is furthermore

indicated that not only the interlayer cations take part in this process but a minor proportion

of other, structural ions as well, differently in the reference and scCO2 environments.


24

POTENTIAL PHASE TRANSITIONS DURING LOSS OF COOLANT

ACCIDENTS IN THE SUPERCRITICAL WATER LOOPS OF VARIOUS

GENERATION IV REACTOR TYPES

Györke G.1, Imre A.R.1,2

1Budapest University of Technology and Economics Department of Energy

Engineering, Budapest, Hungary 2MTA Centre for Energy Research, Budapest, Hungary

Loss of coolant accidents (LOCA) are a serious type of accidents of nuclear reactors, when

the liquid-loop breaks. Because of the break the systems can lose some working fluid,

associated with pressure loss and temperature decrease. In case of traditional nuclear

reactors, where the working (and moderator) fluid is pressurized water, a very fast,

sometimes explosion-like boiling, the so-called “flash” can occur. After the flash, part of the

steam can escape from the pipes, while a smaller part of the vapour stays in the liquid,

producing a mixed, two-phase fluid, which has significantly different properties than the

original one-phase liquid.

Using supercritical water as working fluid has several advantages, as well as a few

disadvantages. One of the advantages is that the supercritical fluid is in permanent one-phase

state, therefore there is no separate liquid and steam phases, at least not in normal working

conditions. Although it was already discussed (Imre et al., 2010), during accidents phase

transitions might happen even in a supercritical loop. In this presentation, we are going to

map the conditions and show the processes when the initially supercritical water might

exhibit flash or even the opposite process (absent during the LOCA of pressurized water

reactors), the sudden steam condensation.

The discussion is valid for all events where sudden pressure-drop can be observed, like for

example blowdown, only in non-accidental cases (like blowdown), one might avoid the

unwanted phase transitions by proper choice of the initial conditions (Ishiwatari et al., 2007).

References:

Imre A.R., Barna I.F., Ézsöl G., Házi G., Kraska T.: Nucl. Eng. Design 240, 1569 (2010)

Ishiwatari Y., Oka Y., Koshizuka S.: Nucl. Eng. Tech. 39, 257 (2007)

POSTER PRESENTATIONS

25


INCREASING THE PREDICTION POWER OF HANSEN SOLUBILITY

PARAMETERS IN SUPERCRITICAL FLUIDS

András Cs.D.1,2, Mátyás L.3, Ráduly B.3, Salamon R.V.1, Székely E.2

1Sapientia Hungarian University of Transylvania, Dept. of Food Science, Csíkszereda

(Miercurea Ciuc), Romania 2Budapest University of Technology and Economics, Department of Chemical and

Environmental Process Engineering, Budapest, Hungary 3Sapientia HUT, Department of Bioengineering, Csíkszereda (Miercurea Ciuc), Romania

The method developed for calculating Hansen parameters for scCO2-polar modifier mixtures has

proved to be suitable for characterizing these solvents. In the ternary Teas diagram, taking into

account all three Hansen parameters of the solvents (p, d), supercritical fluid mixtures,

unlike liquid solvents, are represented by spot, not by singular points. The Teas diagram

possesses two major inconveniences: on the one hand, the quantities have no physical meaning

and, on the other hand, they are distorted because it does not take into account the differences of

the Hildebrand parameters of different solvents, which is an important information loss. The

factors we choose to represent on the ternary diagram possess physical meaning (cohesion energy

density partitions). The distortion was recovered by extending the Teas diagram to a prismatic

three dimensional representation. It was proven, that the Hansen ellipsoid from the Cartesian

coordinate system (d=f(H,p)) is transformed also in ellipsoid in the new coordinate system

(the transformation is pseudo-isomorphic). Despite the corrections made, the interactions

between the solvents and the dissolved materials are not always predicted with sufficient

accuracy. So it would be necessary to made a correction to the value of Hansen parameters of

small molecules on a thermodynamic basis, which could lead to a significant improvement of the

predictive ability of the newly developed method.

Bibliography

András C.D., Mátyás L., Salamon R.V., Szép Al. S.: Szuperkritikus Oldószerek Műveleti és

Analitikai Alkalmazása, Budapest, 2015. május 21

András C.D., Mátyás L., Ráduly B., Salamon R.V.: 50th Anniversary Hansen Solubility Parameters Conference, 5-7 April 2017, York, UK.

Durkee J.B.: Cleaning with Solvents: Science and Technology, William Andrews (2014)

Louwerse M.J., Maldonado A., Rousseau S. et al.: ChemPhysChem 18, 2999 (2017)

Stefanis E., Panayiotou C.: Int. J. Thermophys. 29, 568 (2008)

Williams L.L., Rubin J.B., Edwards H.W.: Ind. Eng. Chem. Res. 43, 4967 (2004)


26

DIFFERENCES IN THE COMPOSITION OF NATURAL OILS

OBTAINED BY CONVENTIONAL AND SCCO2 EXTRACTION

TECHNOLOGIES

Dévényi D.1, Bohus B. 1, Durucskó K. 1, Székely. E1



The demand for the natural and healthy products are increasing continuously nowadays.

Accordingly, the demand of natural extracts and active substances from fruits, vegetables,

herbs and so on are also rising. Steam distillation is the easiest way to extract the essential

oil from certain herbs. Another special technique to get natural oils is the supercritical

carbon-dioxide extraction, which can be used for components separation as well, but

obviously the cost of it is higher than the conventional ones.

A pilot plant steam distiller was constructed and the yields and composition differences of

laboratory and pilot scale steam distillations were compared for different herbs, for example

in the case of the lavender. The lavender oil steam distillation was performed in various

scales laboratory (~ 100 g material), pilot (~ 3 kg material) but also close to industrial scale

(~ 15 kg material). For the lavender oil analysis, a proper GC-FID method was developed

with a temperature profile to determine the limonene, linalool, linalyl acetate and terpinen-

4-ol components. Internal standard method was used for the quantification, where menthone

was the component in addition. The outcomes have been shown, that the scale has a

significant effect for the oil quality, where the linalyl acetate quantity nearly doubled and

the linalool decreased by one third by the scale. The limonene and terpinen-4-ol quantity

stayed almost constant in each size. The investigated main rate of components increased

approximately by 10 % from lab to industrial scale.

Dried saw palmetto extraction was investigated with scCO2 pilot plant extractor with

pressure range between 300 and 450 bar. Determination of samples fatty acids sample

preparation was used based on literature [1] and a GC-FID analysis method was developed.

Results showed, that the pressure and temperature of the separators has low effect for

saturated (lauric acid (12:0), myristic acid (14:0), palmitic acid (16:0); oleic acid (18:0)) and

unsaturated acids (oleic acid (18:1), linoleic acid (18:2)). Separation conditions affected

mainly the ratio of the free fatty acids only. Comparing the results of the fatty acid

composition determined by results on hawthorn for example the major role played was that

of the plant material itself.

This work was supported by the Higher Education Excellence Program of the Ministry of

Human Capacities in the frame of Biotechnology research area of Budapest University of

Technology and Economics (BME FIKP-BIO).

References:

[1] Bartolomé O.A., Garcia A.C., Szekely E., Skerget M., Knez Z., Journal of

Supercritical Fluids, 120 (1), 132-139 (2017)


27

OPTICAL RESOLUTION OF IBUPROFEN BY ANTISOLVENT

PRECIPITATION OF ITS DIASTEREOMERIC SALTS

Horváth A.1, Lőrincz L.1, Mihalovits M.1, Sohajda T.2,

Komka K.1, Székely E.1


Environmental Process Engineering, Budapest, Hungary 2Cyclolab LtD., Budapest, Hungary

The demand for optically active products is constantly growing in several branches of

chemical industry. Thus, technologies that are capable of large-scale production of

enantiopure compounds, while remaining economical and having a low environmental

impact, receive increasing significance. Optical resolution with supercritical carbon dioxide

as antisolvent is an innovative technique with a promise to fulfill the above aspects. As a

model compound ibuprofen (IBU) was selected. The acid was reacted with half a molar

equivalent of (R)-1-phenylethane-1-amine (PhEA).

The basics of the used GAS (gas antisolvent precipitation) method: upon the addition of half

an equivalent of resolving agent to an organic solution (ethanol, methanol or 1-propanol) of

ibuprofen (IBU). One of the enantiomers forms a diastereomeric salt. By contacting this

solution with supercritical carbon dioxide in a stirred autoclave (at a given pressure and

temperature) the salt precipitates. The organic solvent and the unreacted enantiomer can be

removed by a constant flow of pure carbon dioxide (maintaining constant pressure). After

the depressurization of the reactor, the deposited salt is easily collected in its solid state.

Enantiomer purity was measured by capillary electrophoresis, while the crystal structure and

morphology were determined by powder X-ray diffraction and scanning electron

microscopy. The solubility of solvents can be generally characterized by the Hansen

solubility parameter. This would allow the comparison of various systems, although seldom

had it been applied to antisolvent crystallizations before.

The effects of temperature and pressure were studied in the ranges of 10-20 MPa and 35-

45 °C, while effects of solvent quality and quantity were also examined. Obtained

diastereomeric excess values were in the range of 0-65%. A solubility parameter model was

fitted to these measurements, which is capable of describing the pressure, temperature and

solubility parameter dependency of selectivity (the product of the diastereomeric excess and

yield of the raffinate salt) in the aforementioned ranges.

We highly appreciate the help of Prof. János Madarász in the analysis of the solid phases.


in the frame of K108979 project.


28

SURFACE EXCESS ISOTHERMS OF ORGANIC MODIFIER AND

CARBON DIOXIDE MIXTURE IN SUB- OR SUPERCRITICAL FLUID

CHROMATOGRAPHY

Kazmouz Y.M.1*, László Sz.1*, Rédei Cs.1, Bacskay I.2, Felinger A.1,2

1University of Pécs, Department of Analytical and Environmental Chemistry, Pécs,

Hungary 2MTA-PTE Molecular Interactions in Separation Science Research Group,

Pécs, Hungary *These authors contributed equally to this work

The surface excess isotherms of an organic modifier (methanol) from liquid carbon dioxide

on reversed-phase silica stationary phases were measured using the minor disturbance

method. The excess isotherms were calculated based on the retention of the organic solvent,

for which the signals were recorded using UV-detection in the whole composition range of

the organic modifier/carbon dioxide mixtures. The experiments were carried out under two

conditions of temperature and back pressure (26 ◦C, 145 bar) and (40 ◦C, 250 bar). All the

excess isotherms were determined at a constant volumetric flow rate set at 1 cm3/min. Each

column was equilibrated successively with pure organic modifier and with mixtures of the

organic modifier with liquid carbon dioxide containing 95, 90, 80, 70, 60, 50, 40, 30, 20, 10,

5, 2, 1, 0.5, 0.2 and 0.1 (v/v%) of the modifier.

The retention volumes were calculated as a mean from two replicate injections and were

corrected for the extra-column volume of the system. For mobile phase compositions with a

methanol fraction above 10 % (v/v) there are only small changes in the retention volume and

the volume is approximately the same as the void volume. Smaller fraction of methanol in

the mobile phase below 0.5% results in a larger retention volume.

From the shape of methanol’s excess isotherm, a pronounced wide negative part related to

the preferential adsorption of carbon dioxide onto hydrophobic part of bonded ligands of the

stationary phase surface is identified.

Our results show that the adsorption of CO2 on the hydrophobic ligands is much stronger

than the adsorption of methanol in both subcritical and supercritical conditions. Methanol

can be adsorbed on the residual silanols and other polar groups, if they are present in the

structure of stationary phase. The location of the maximum of the excess isotherm for

methanol was at small concentration of the organic modifier.

References:

[1] Vajda P., Guiochon G.: J. Chromatogr. A, 1308, 139-143 (2013)


29

EXTRACTING AND ANALYSING NON-POLAR COMPONENTS OF

HAWTHORN BERRIES

Kubovics M.1, Al-Hamimi S.2, Huszár Gy.3, Turner C.2, Székely E.1


Environmental Process Engineering, Budapest, Hungary 2Lund University, Department of Chemistry, Lund, Sweden 3Taravis Ltd., Sárvár, Hungary

Over the last few years several scientific papers were made about extracting and analysing

the composition of different parts of hawthorn. Many of them are focusing on the polar

components of the plant, while less attention has been given to non-polar fractions. In this

presentation two purposes for extracting non-polar components are introduced.

One goal was to get comprehensive picture of hawthorn berries with studying the non-polar

extracts made with two different extraction techniques and solvents. Namely analytical-scale

CO2 supercritical fluid extraction and pressurised liquid extraction with n-heptane –

isopropanol (3:2, v:v) were carried out with two stocks of hawthorn berries harvested in

different years. The non-polar fractions were then analysed on an Acquity UPC2

(UltraPerformance Convergence Chromatography), connected to Xevo 2G QTOF-MS

(Quadrupole Time-of-Flight Mass Spectrometry), the MS was operated in positive and

negative ESI mode. The extraction and the analytical investigation were performed in Green

Technology Group of Lund University, Sweden.

Several compounds were identified or tentatively assigned on the basis of their accurate mass

and the fragmentation patterns. A comparison on the basis of both quantity and quality of

different compounds was performed in order to determine the differences between the two

stocks and the two extraction techniques. The identified components belonged to fatty acids

(FA), di- and triacylglycerols (DAG,TAG) and phosphatidylcholines (PC). Usually TAG,

DAG, PC and longer chain fatty acids were extracted with n-heptane – isopropanol mixture

in higher rate, while supercritical fluid extracts contain larger amount of shorter chain fatty

acids.

The other purpose was to carry out pilot-scale extraction with the berries to pretreat the plant

in order to reduce the amount of oily and fatty components. The pretreatment was needed to

avoid formation of emulsion in the further extraction steps with polar solvent. The final

extract was used in a drinking test for treating chickens with weak heart and cardiovascular

system.

In the CO2 supercritical fluid extraction - which was carried out under the maximum

available pressure in the apparatus- about 2.5% extraction yield was achieved. Supercritical

pretreatment is a suitable method considering economical and environmental aspects in case

of products for the food industry.

Part of this project was supported by the Erasmus+ programme of the European Union.


30

STUDYING THE COMPETITIVE ADSORPTION OF ALKYLBENZENES

AND METHANOL IN SUPERCRITICAL FLUID CHROMATOGRAPHY

Rédei, Cs.1, Felinger, A.1,2

1University of Pécs, Department of Analytical and Environmental Chemistry, Pécs,

Hungary 2MTA-PTE Molecular Interactions in Separation Science Research Group, Pécs,

Hungary

Supercritical fluid chromatography (SFC) is an analytical method that is capable of faster

separations and reduced solvent consumption compared to liquid chromatography (LC)

while also achieving excellent efficiency. Due to the nature of carbon-dioxide that serves as

mobile phase, eluent strength is well-tunable by adjusting temperature, pressure and the

amount of organic modifier. Of course, this could not be possible without today’s state of

the art instrumentation. Recently, Gritti experienced an anomaly considering the retention

behaviour of alkylbenzenes using a heavily modified Waters ACQUITY UPC2 System [1].

These small molecules are ideal for studying the processes taking place in the

chromatographic column.

Therefore, the aim of this work is to study the retention of several n-alkylbenzenes on an

alkylamide stationary phase using a standard UPC2 System while also assessing the effect

of different sample solvents on chromatographic efficiency. The results show that even a

small amount of methanol overloads the column and a competitive adsorption takes place

between the analytes and the solvent. This is indicated by the changes in column efficiency,

retention factors and peak widths. The selected experimental conditions provide that the

density of the mobile phase does not change significantly along the column so the

phenomenon can be modelled as in LC. The concentration of the analytes is negligible

compared to the amount of methanol – but their adsorption is influenced by the solvent –

while the adsorption of methanol remains unaffected by the alkylbenzenes. Thus, the

competition can be described by determining the individual adsorption isotherms for both

the analytes and the solvent then a competitive isotherm can be written and calculated as

well to model the solvent effect.

Reference:

[1] Gritti F.: J. Chromatogr. A 1468, 209-216 (2016)


31

SUPERCRITICAL FLUID DYEING OF POLYCARBONATE WITH A

DISPERSE DYE

Unoka G.1, Péter-Szabó B.1, Varga D.2, Gamse T.2, Székely E.1


Environmental Process Engineering, Budapest Hungary 2Graz University of Technology, Institute of Chemical Engineering and

Environmental Technology, Graz, Austria

Supercritical carbon dioxide technology offers a fast and low temperature route for

impregnation of solid materials with various components, like antifungal [1], anti-

inflammatory [2] or simply colored [3] compounds. Dyes and pigments are conventionally

incorporated in polycarbonate (PC) resins during their manufacture. This method suffers

from two general drawbacks. First, the high melt viscosity of the resin makes it difficult to

disperse the color uniformly and second, the high temperatures used in molding the resin

exclude the use of thermally labile dyes. Our goal was to dye PC pellets with Disperse Red

13 (DR13) with Supercritical Fluid Dyeing technology (SFD) in a batch and in a semi-

continuous process. The efficiency of impregnation was measured by UV-VIS spectroscopy

at 503 nm after the pellets was solved in dichloromethane.

Solubility data was measured for DR13 in supercritical carbon dioxide (scCO2) with a semi-

continuous device. [4] The batch experiments were performed at different pressures,

temperatures and various impregnation time in autoclave. Furthermore, a semi-continuous

supercritical impregnation device has been assembled and SFD process was investigated on

PC pellets as well with this appliance by the use of DR13. Experiments were performed at

10 MPa and 40 °C with 5 different impregnation times. This process was successfully

applied and resulted a more controllable process than the batch SFD.

References

[1] Kjellow A.W., Henriksen O.: J. Supercrit. Fluids 50, 297–304(2009)

[2] Gamse T., Marr R., Wolf C., Lederer Klaus.: Supercritical CO2 impregnation of

polyethylene components for medical purposes, 7th Symposium on Modern

Technologies and Economic Development, Leskovac, SERBIA, OCT 19-20, 2007

[3] Bach E., Cleve E., Schollmeyer E.: Rev. Prog. Color. 32 (1), 88–102 (2002)

[4] Varga D., Alkin S., Gluschitz P., Péter-Szabó B., Székely E., Gamse T.: Journal of

Supercritical Fluids 116, 111–116 (2016)

ESS-HPT 2018

The European Summer School in High Pressure Technology

8th July – 22nd July 2018

University of Maribor, Slovenia

and

Graz University of Technology, Austria

The European Summer School in High Pressure Technology is promoted by the members of the Working Party „High Pressure Technology” of the European Federation of Chemical Engineering (EFCE). All members, recognised European experts, both in the theoretical aspects and in the industrial applications of high pressure technologies, will present the keynote lectures.

For further information please contact the coordinator by email

Ao.UnivProf.Dipl.-Ing.Dr.techn. Thomas Gamse

Institute of Chemical Engineering and Environmental Technology

Graz University of Technology

Inffeldgasse 25/C, A-8010 Graz, Austria

Email: [email protected]

applications of supercritical fluids 2018...

Documents