photocatalytic removal of organic micropollutants from the

2
-: Did you know that... There are 18 deliverables to be completed by the end of the pro- ject, including: Dissemination activities A protocol on synthesis of various TiO2-RGO composite catalysts A technical report on catalyst characterisation A technical report on photo- catalytic degradation on cho- sen emerging pollutants A technical report on the design, setup and operation of a bench scale photochemi- cal reactor and a micro- filtration system pilot treat- ment unit for the recovery of the catalyst University of Cyprus NIREAS-International Water Research Center Technical University of Crete S.K Euromarket Ltd Heterogeneous semiconductor photocatalysis is an advanced oxidation process which makes use of catalysts such as TiO2 to produce radicals which, in the presence of sunlight can break down organic micropollutants, to less harmful substances which do not pose a threat to humans and the environment. Despite the usefulness of the application of heterogeneous photocatalysis, it has the following drawbacks, which this project seeks to tackle by coupling the process with graphene: The abovementioned issues are addressed by PhotoGraph for the effective application of TiO2 photocatalysis for degradation of trace organic pollutants, by: Coupling TiO2 with graphene for minimizing charge carrier recombination. Employing commercially available carbon doped TiO2 catalysts which absorb in the visible region of the electromagnetic spectrum. Applying a post-treatment for the separation and recovery of TiO2, based on cross-flow microfiltration. This project will investigate the degradation of selected contaminants of emerging concern which pose risk for human health and the environment. The PhotoGraph (ΑΕΙΦΟΡΙΑ/ΑΣΤΙ/0311(ΒΙΕ)/33) project is co-funded by the Republic of Cyprus and the European Regional Development Fund Photocatalytic Removal of Organic Micropollutants from the Aqueous Phase using TiO 2 coupled with Graphene as a Photocatalyst ΑΕΙΦΟΡΙΑ/ΑΣΤΙ/0311(BIE)/33 PhotoGraph Newsletter March2013 The degradation of the four model compounds was examined by the University of Cyprus in distilled water under simulated solar irradiation, in laboratory conditions. Environmentally relevant concentrations of the four organic micro- pollutants are tested to see how the compounds behave at real environmental concentrations. The initial tests of photocatalytic degradation were done primarily for each catalyst and each organic compound separately, and then for the organic compounds together in mixture. Figure 3 shows the photocatalytic degradation of the anti- biotic sulfamethoxazole using 6 commercially available TiO2 catalysts. P25 Degussa was prov- en to be the most efficient one with complete removal in 60 minutes of treatment under solar irradiation. WP5 - Testing the photocatalytic efficien- cy of the TiO2 - Reduced Graphene Oxide catalysts for the degradation of emerging organic pollutants Figure 2. UV-Vis absorption spectrum of an aqueous suspen- sion of exfoliated graphene oxide. Figure 1. FT-IR spectra of graphite oxide samples The particle and surface properties of the cata- lysts regarding their reactivity using analytical and microscopic techniques such as FT-IR and UV-Vis spectrum measurements were characterised by the Technical University of Crete. The main re- sults of this WP are summarised in Figure and Figure 2 . WP4 - Characterisation of the synthesized photocatalysts and toxicity measurements Background The characterisation of samples is in progress us- ing additional characterisation techniques in order to reveal their main structural features. Figure 3. Degradation rate of sulfamethoxazole using commer- cially available catalysts. The innovative element of this project lies in the synthesis of newly developed catalysts which have not been used before and include the synthesis of TiO2-graphene composite catalysts. P25 Degussa Kronos 7000 PC 105 PC 500 UV 100 Kronos 7001

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Page 1: Photocatalytic Removal of Organic Micropollutants from the

-:

Did you know that...

There are 18 deliverables to be

completed by the end of the pro-

ject, including:

Dissemination activities

A protocol on synthesis of

various TiO2-RGO composite

catalysts

A technical report on catalyst

characterisation

A technical report on photo-

catalytic degradation on cho-

sen emerging pollutants

A technical report on the

design, setup and operation

of a bench scale photochemi-

cal reactor and a micro-

filtration system pilot treat-

ment unit for the recovery of

the catalyst

University of Cyprus

NIREAS-International Water

Research Center

Technical University of Crete

S.K Euromarket Ltd

Heterogeneous semiconductor photocatalysis

is an advanced oxidation process which makes

use of catalysts such as TiO2 to produce

radicals which, in the presence of sunlight can

break down organic micropollutants, to less

harmful substances which do not pose a threat

to humans and the environment.

Despite the usefulness of the application of

heterogeneous photocatalysis, it has the

following drawbacks, which this project seeks

to tackle by coupling the process with

graphene:

The abovementioned issues are addressed by

PhotoGraph for the effective application of TiO2

photocatalysis for degradation of trace organic

pollutants, by:

Coupling TiO2 with graphene for minimizing

charge carrier recombination.

Employing commercially available carbon

doped TiO2 catalysts which absorb in the

visible region of the electromagnetic spectrum.

Applying a post-treatment for the separation

and recovery of TiO2, based on cross-flow

microfiltration.

This project will investigate the degradation of

selected contaminants of emerging concern which

pose risk for human health and the environment.

The PhotoGraph (ΑΕΙΦΟΡΙΑ/ΑΣΤΙ/0311(ΒΙΕ)/33) project is co-funded by the Republic of Cyprus and the European Regional Development Fund

Photocatalytic Removal of Organic Micropollutants from the Aqueous

Phase using TiO2 coupled with Graphene as a Photocatalyst

ΑΕΙΦΟΡΙΑ/ΑΣΤΙ/0311(BIE)/33

PhotoGraph Newsletter March2013

The degradation of the four model compounds

was examined by the University of Cyprus in

distilled water under simulated solar irradiation,

in laboratory conditions. Environmentally relevant

concentrations of the four organic micro-

pollutants are tested to see how the compounds

behave at real environmental concentrations.

The initial tests of photocatalytic degradation

were done primarily for each catalyst and each

organic compound separately, and then for the

organic compounds together in mixture. Figure 3

shows the photocatalytic degradation of the anti-

biotic sulfamethoxazole using 6 commercially

available TiO2 catalysts. P25 Degussa was prov-

en to be the most efficient one with complete

removal in 60 minutes of treatment under solar

irradiation.

WP5 - Testing the photocatalytic efficien-

cy of the TiO2 - Reduced Graphene Oxide

catalysts for the degradation of emerging

organic pollutants

Figure 2. UV-Vis absorption spectrum of an aqueous suspen-sion of exfoliated graphene oxide.

Figure 1. FT-IR spectra of graphite oxide samples

The particle and surface properties of the cata-

lysts regarding their reactivity using analytical and

microscopic techniques such as FT-IR and UV-Vis

spectrum measurements were characterised by

the Technical University of Crete. The main re-

sults of this WP are summarised in Figure and

Figure 2 .

WP4 - Characterisation of the synthesized photocatalysts and toxicity measurements

Background

The characterisation of samples is in progress us-

ing additional characterisation techniques in order

to reveal their main structural features. Figure 3. Degradation rate of sulfamethoxazole using commer-cially available catalysts.

The innovative element of this project lies in

the synthesis of newly developed catalysts

which have not been used before and include

the synthesis of TiO2-graphene composite

catalysts.

P25 Degussa

Kronos 7000

PC 105

PC 500

UV 100

Kronos 7001

Page 2: Photocatalytic Removal of Organic Micropollutants from the

Dr. Despo Fatta-Kassinos

Assistant Professor

Work team:

Dr. Irene Michael

Dr. Costas Michael

Ms. Popi Karaolia

Department of Civil and Environmen-

tal Engineering

NIREAS-International Water

Research Center

University of Cyprus

Nicosia, Cyprus

Tel: (+ 357 )22 883515

Fax: (+ 357) 22 895080

[email protected]

Dr. Nikos Xekoukoulotakis

Assistant Professor

Work team:

Dr. Danae Venieri

Ms Katerina Drosou

Department of Environmental

Engineering

Technical University of Crete

University Campus

GR-73100 Chania, Greece

Tel: (+30) 28210 37772

Fax: (+30) 28210 37848

[email protected]

The partners had the opportunity to get together and dis-

cuss the preliminary project technical matters and the work

to follow on the work packages of the project, on the 15th of

June, 2012 at the Nireas-IWRC premises. The project time-

table and the responsible persons for each working pack-

age were allocated. The analytical timeframe of the work

package actions was also prepared. The prepared reports

toward the completion of WP1 are:

1st progress report after 6 months

2nd progress report after 1 year

The synthesized catalysts were made using a methodology

involving chemical pre-oxidation and oxidisation of graphite

using the Hummer’s method and its exfoliation, followed by

reduction of the exfoliated graphene sheets in the presence

of TiO2, achieving simultaneous hydrothermal formation of

TiO2 - reduced graphene oxide composites. This work pack-

age is implemented by the project team located at the Tech-

nical University of Crete.

WP1 - Project Management

Various actions were prepared for result dissemination:

A notice board

Newsletters

A website (www.photographproject.com)

An article in the UCY newspaper ‘Κοινότητα’

An article in the newspaper ‘Καθημερινή’

An article in the online portal ‘typologos.com’

The project work was also presented in the following scien-

tific conferences:

European Conference/Workshop on the Synthesis, Char-

acterisation and Applications of Graphene (Myconos,

September 2012)

Panhellenic Catalysis Symposium (Chania, October

2012)

WP3 - Synthesis of TiO2—Reduced Graphene Oxide

Composite Photocatalysts

The actions carried out during the first year of the project

were implemented successfully by the consortium which is

made out of:

University of Cyprus

Technical University of Crete

S.K. Euromarket Ltd.

WP2 - Dissemination of results

The outstanding properties of graphene which make it an interesting material to be studied are:

High specific surface area which increases adsorption of pollutants

Transparent one-atom thickness

Extended light absorption range toward the visible region of the electromagnetic spectrum

Excellent electron mobility through the charge transportation and electron/hole separation in TiO2

The contaminants of emerging concern under investigation include:

The antibiotic sulfamethoxazole, a sulfonamide antibiotic widely used in medicine.

The synthetic estrogen 17α-ethynylestradiol, a synthetic estrogen which has been found to pose es-

trogenic effects at very low concentrations.

The X-ray media sodium diatrizoate, shown to have estrogenic and mutagenic activity. X-ray media

are used for medical imaging in order to enhance the contrast between blood vessels and organs.

The illicit drug cocaine, which belongs to a group of substances recently emerging as a very important

class of organic micro-pollutants in aquatic bodies.

Contaminants of emerging concern

Main activities and results