Research Article Photocatalytic Degradation of Anthracene ... · Research Article Photocatalytic Degradation of Anthracene in ... ese radicals oxidize target molecule (Anthracene)

Research ArticlePhotocatalytic Degradation of Anthracene inClosed System Reactor

Faiq F Karam1 Falah H Hussein2 Sadiq J Baqir2 Ahmed F Halbus2

Ralf Dillert3 and Detelf Bahnemann3

1 Chemistry Department College of Science Al-Qadisiya University Al Deewaniya 58002 Iraq2 Chemistry Department College of Science Babylon University Hilla 51002 Iraq3 Institut fur Technische Chemie Leibniz Universitat Hannover 30167 Hannover Germany

Correspondence should be addressed to Faiq F Karam faiqkaramyahoocom

Received 3 April 2014 Revised 24 May 2014 Accepted 7 June 2014 Published 8 July 2014

Academic Editor Chuanyi Wang

Copyright copy 2014 Faiq F Karam et al This is an open access article distributed under the Creative Commons Attribution Licensewhich permits unrestricted use distribution and reproduction in any medium provided the original work is properly cited

Polycyclic aromatic hydrocarbons (PAHs) represent a large class of persistent organic pollutants in an environment of specialconcern because they have carcinogenic and mutagenic activity In this paper we focus on and discuss the effect of differentparameters for instance initial concentration of Anthracene temperature and light intensity on the degradation rate Theseparameters were adjusted at pH 68 in the presence of the semiconductormaterials (TiO

2) as photocatalysts overUV lightThemain

product of Anthracene photodegradation is 910-Anthraquinone which isidentified and compared with the standard compound byGC-MS Our results indicate that the optimum conditions for the best rate of degradation are 25 ppm concentration of Anthraceneregulating the reaction vessel at 30815 K and 25mWcm2 of light intensity at 175mg100mL of titanium dioxide (P25)

1 Introduction

Polycyclic aromatic hydrocarbons (PAHs) constitute animportant and hazardous group of priority contaminates[1] Several researchers determined the concentrations ofthese compounds by different chromatographic techniquesfor instance HPLC [2ndash4] GC-MSMS in [5] and GC-MSin [6 7] The main processes that successfully eliminatedPAHs from the environment included the microbiologicaltransformation and degradation bioaccumulation biologicaluptake volatilization photooxidation and chemical oxida-tion [8] Photolysis and ozonation are the most importantmethods for transformation for most PAHs adsorbed onnatural substances in an environment [9] Photolysis of PAHsled to the formation of photodimers and photooxidationproducts [10] In recent years the release of toxic and organiccontaminants into aquatic environment as a result of humanactivities has drawn much attention and is considering abaffling problem facing researchers today [11] Zinc oxideand titanium dioxide are universally considered as the mostimportant photocatalysts due to their lower cost and their

considerably low band gap energy (sim32 eV) [12] Nanoparti-cles of titanium dioxide were considered to be more efficientthan bulk powder in photocatalytic field [13] Several previousworks used titanium dioxide as catalyst for degradation ofdifferent organic pollutants [14ndash16]

Semiconductors have been used for pollutants degrada-tion in water to be less harmful inorganic material Bothcatalysts titanium dioxide and zinc oxide have photocat-alytic properties which made these catalysts the best forphotodegradation of water pollutants [17] Attention has beenfocused in the past decade on using nanocrystalline TiO

2

as a photocatalyst for the organic pollutants degradationTiO2semiconductor has a wide band gap about 32 eV which

corresponds to the UV-range radiation The formation ofan electron hole pair occurs within the conduction andvalance bands of TiO

2semiconductor after absorption in

UV range Water molecules can be oxidized to hydroxylradical by positive hole Scheme 1 shows the mechanismdiagram for photodegradation of Anthracene The hydroxylis a radical frequent and powerful oxidant The oxidationof organic pollutants seems to be mediated by a series of

Hindawi Publishing CorporationInternational Journal of PhotoenergyVolume 2014 Article ID 503825 6 pageshttpdxdoiorg1011552014503825

2 International Journal of Photoenergy

CB

VB

UV

eminus

h+

O2

O2minus∙

Reduction

H2O∙OHO

O +O2

Oxidation

Scheme 1 Mechanism diagram of photocatalytic degradation for Anthracene

reactions started by hydroxyl radical on the TiO2surface

Recombination for the produced hole from valance band andseparated electron from conductive band it can appear eitherin the volume or on the surface of the semiconductor particleaccompanied with heat releasing To this end both UV lightsource and TiO

2are necessary for photooxidation reaction

to occur [18] The photodegradation of PAHs compounds inwater using TiO

2catalyst has proved high efficiency in [19]

Furthermore many researchers dealt with the PAHs inwater by photocatalytic degradation for TiO

2 Woo et al

in [20] investigated photocatalytically oxidation using TiO2

of 5 selected PAHs namely naphthalene acenaphthylenephenanthrene Anthracene and benzo[a]anthracene Gu etal in [21] studied degradation of phenanthrene on soilsurfaces photocatalytically with the addition of nanopar-ticulate anatase TiO

2under UV-irradiation Vela et al in

[22] discussed photocatalytic processes using semiconductormaterials (ZnO and TiO

2) to remove the residual con-

centrations of several PAHs from groundwater Theurichet al in [23] reported themechanism of the photocatalytictransformation of naphthalene and Anthracene qualitativelyin aqueous suspensions of titanium dioxide Indeed catalystTiO2can play as efficient photocatalyst in the oxidation of

PAHs and convert it to safer compounds especially withAnthracene Fluorene and Naphthalene by artificial or sun-light illumination [19 24] To this end our aim in the presentpaper is to study the effect of photocatalytic reactions onthe degradation of Anthracene using titanium dioxide underdifferent experimental conditions

UV illumination of TiO2yields valence band holes and

conduction band electrons (1) which interactwith the surfaceadsorbedmolecular oxygen to give superoxide radical anionsO2

minus∙ (2) and finally the water produces radicals of HO∙ (3)[25] These radicals oxidize target molecule (Anthracene) toAnthraquinone (4)

TiO2+ ℎ] 997888rarr h+vb + e

minus

cb (1)

eminuscb +O2 997888rarr O2

minus∙ (2)

h+vb + TindashOH2 997888rarr HO∙ads +H+ (3)

HO∙ads + Anthracene 997888rarr Anthraquinone (4)

2 Experimental Procedure

21 Chemicals and Reagents Anthracene was purchasedfrom Sigma Aldrich Germany and used without furtherpurification Acetonitrile (anhydrous ge9998) Dichloro-methane (anhydrousge9998)Acetone ethyl acetate (anhy-drous ge9998) and methanol HPLC-gradient grade werepurchased also from Sigma Aldrich Germany Titaniumdioxide particles were purchased from Degussa (P25)anhydrous Na

2SO4(extra pure Allied Signal Riedel-demdash

Germany)

22 Preparation of Stock Solution of Anthracene A set ofdilutions of Anthracene solution at the concentration of100mgL were made in the following solvents methanoldichloromethane acetonitrile ethyl acetate and acetoneAnthracene solutions in the above solvents were preparedand stored in room temperature (20 plusmn 2∘C) in dark placeto keep it from the light degradation Calibration curvefor Anthracene solution has been achieved by preparationseveral concentrations (01 05 1 2 4 8 16 and 30) mgL Allglassware used for experiments was washed in chromic acidmixture for 12 h with methanol deionized water and acetoneand then dried at 110∘C for 3 h

23 Solid Phase Extraction and Sample Preparation Solidphase extraction (SPE) method was used to extract theAnthracene from the mixture (aqueous solution at differentsolvents) by Supelcoclean ENV-18 solid phase extractiontube After passing the specific volume of aqueous solutionthrough extraction column the extract was treated withanhydrous Na

2SO4to remove all the water content from the

extract and then it was concentrated by rotary evaporator(BUCHI-RE121-Swizerland made) in temperatures below35∘C by water bath (BUCHI 461MetrohmSwiss made) to bein volume 1mLThen sampleswere analyzed byGC2010 (Shi-madzu Japan) The study revealed that the Anthracene levelhad no effect on the percent decrease of the compoundduringevaporation process for the solvent The average recovery ofanalytes for every liquid media and corresponding relativestandard deviations RSD (119899 = 5) were represented in Table 1Chromatographic conditions are listed in Table 2

International Journal of Photoenergy 3

Table 1 The average recovery of Anthracene and relative standarddeviations RSD (119899 = 5)

Organic solvents Recovery RSDMethanol 91 03Dichloromethane 88 05Acetonitrile 92 02Ethyl acetate 81 04Acetone 79 34

Table 2 Chromatographic conditions were used for determinationAnthracene by GC

Parameters DetailsColumn Type Hp5 (60m lowast 025mm lowast 025 120583m)Injection volume 1 120583LInjector mode Split less temp = 250∘CCarrier gas High purity heliumDetector Type FID temp = 310∘C

24 Photolysis Experiments The experiments were car-ried out in glass dual wall reactor closed system typeto keep the temperature constant using chiller (Julabomodel EHGermany) as temperature controller Agitationof the reaction mixture was provided by a magnetic stirrer(Heidolph-Mr3001) The photoreactor operated in a batchmode The study was carried out for selected compoundAnthracene (Sigma Aldrich) without additional purificationThe pH of the reaction solution adjusted about 68 pH byadding an exact volume of Sodiumhydroxide or sulfuric acid

25 Kinetics of the Photocatalytic Process Kinetics ofAnthracene degradation was calculated by the first-orderequation

119862

119905= 119862

0sdot 119890

minus119896119905 (5)

or

ln(119862

0

119862

119905

) = 119896119905 (6)

where 1198620 119862119905are the PAH concentration at times (zero

and 119905) respectively and 119896 is the rate constant First-orderdegradation rate constants were determined by regressionanalysis

3 Results and Discussion

Several parameters were studied to indicate the effect of thesedegradation rates as follows

31 Effect of the Initial Anthracene Concentrations The effectof initial Anthracene concentration on the reaction rate isthe first parameter studied in this work Figure 1 shows thatAnthracene concentrations decrease with time increasesTherate of degradation increases as the initial concentrationincreases as well For photochemical reactions the higher

ln C

0C

t

0123456789

0 30 60 90 120 150 180 210Time (min)

25ppm10ppm ppm1

ppm5

Figure 1 The changes of ln(1198620119862

119905) with irradiation times on

different Anthracene concentrations by TiO2

00005

0010015

0020025

0030035

0040045

005

0 5 10 15 20 25 30Concentration (ppm)

k(m

inminus1)

Figure 2 Effects of initial Anthracene concentrations at a rateconstant

0

1

2

3

445

35

25

15

05

5

0 30 60 90 120 150 180 210Time (min)

ln C

0C

t

30815K29815K

28815K27815K

Figure 3 Effect of temperature on the degradation rate ofAnthracene

concentration causes a higher light absorption and conse-quently accelerates the degradation rate [26] Figure 2 showsthe relation between rate constant and initial concentrationsof Anthracene

32 Effect of Temperature The oxidation of Anthracenemolecule was studied at different temperatures to indicate


31 32 33 34 35 36 370

minus1

minus2

minus3

minus4

minus5

ln k

(1000T) (K)

Ea = 1276kJ molminus1

Figure 4 Arrhenius plot for photocatalytic degradation ofAnthracene on TiO

2at (27815ndash30815) K

Time (min)

ln C

0C

t

10

9

8

7

6

5

4

3

2

1

0

0 30 60 90 120 150 180 210

1mWcm2

15mWcm2

20mWcm2

25mWcm2

Figure 5 Effect of light intensity on the degradation rate ofAnthracene

00 05 1 15 2 25 3

0005001

0015002

0025003

0035004

0045005

k(m

inminus1)

Light intensity (mW cmminus2)

Figure 6 The effect of initial light intensity on the rate constant

25

50

75

00

TIC15205 (1217)18015 (1245)

25 50 75 100 125 150 175 200 225 250

(times1000000)

Figure 7 Chromatogram of GC-MS for standard 910-Anthraquinone and produced by oxidation of Anthracene beforeexposure to UV light

()

1500 1750 2000 2250 2500 2750 3000 3250 3500

0

50

100138

170

302217 310253 280 323 334 346

Figure 8 Mass spectra for standard 910-Anthraquinone beforeexposure to UV light

25 50 75 100 125 150 175 200 225 250

TIC

05

10

(times10000000)

Figure 9 Chromatogram of GC-MS for standard 910-Anthra-quinone after exposure to UV light

()

1500 1750 2000 2250 2500 2750 3000 3250 3500

0

50

100 137

160

244 274207 296 310324 333 346

Figure 10 Mass spectra for standard 910-Anthraquinone afterexposure to UV light

the best one at which the degradation rate is fastest Figure 3shows the effect of temperature on the concentration ofAnthracene with time of reaction Figure 4 illustrates theArrhenius plot for the relation between ln119896 and 1119879 activa-tion energy calculated by Arrhenius equation

The influence of temperature on the degradation rateis typical The greatest increase of the rate of degradationabout two times can be achieved after about 180min at30815 K initial rateswithin the first 30min appear to increasewith increasing the temperatureThis phenomenon is relatedto the effect of temperature on the stability of Anthracenemolecule Luo et al [27] reported that higher temperatureslightly enhances the rate constant of Pyrene

33 Effect of Light Intensity UV light intensity has animportant role in the process of photocatalytic degradationFigure 5 shows effect of light intensity on the degradationrate of Anthracene molecule This figure indicates thatthe reactions followed pseudo-first-order rate constant withincreasingUV light intensity from 1ndash25mWcm2The resultsindicate the perfect degradation at light value 25mWcm2

Therefore when light intensity increases the numberof photons increases which means that the formation ofelectrons and holes increases and hence electron-holerecombination is negligible However at the lower lightintensity electron and hole pair separation competes withrecombination which in turn decreases the formation of freeradicals [28] causing less effect on the rate of degradation ofthe Anthracene as shown in Figure 6


O O

OAnthracene Anthrone 9 10 -Anthraquinone

Figure 11 Proposed pathway degradation of Anthracene

34 Photodegradation Products of Anthracene The majorproduct for photodegradation of Anthracene is 910-Anthraquinone Anthraquinone is characterized by GC-MS(2010-SHIMADZU) Standard solution 25 ppm of 910-Anthraquinone (Sigma Aldrich) was prepared and comparedwith that produced by oxidation Figures 7 and 8 illustratethat there are no differences between them The proposeddegradation pathway of Anthracene is as in Figure 11

During the photocatalytic degradation experiments withAnthracene only 910-Anthraquinone was detected as anintermediate in agreement with Theurich et al [23] Figures9 and 10 show the GC chromatogram and mass spectra for910-Anthraquinone after exposure to the light intensity inthe same environment of perfect conditions for Anthracenedegradation

4 Conclusions

The photocatalytic degradation of Anthracene using artificialUV light has been achieved The observations of theseinvestigations demonstrate the importance of selecting theoptimum parameters for degradation to obtain a high degra-dation rate which is considered essential for any applica-tion of photocatalytic oxidation processes The experimentalwork in controlled pH media at closed system reactor hasfound that the main product of oxidation of Anthraceneis 910-Anthraquinone which is safer for environment thanAnthraceneThe rate of photodegradation in presentUV lighthas been found to be maximum in neutral medium withoptimum concentration of 25 ppm of Anthracene The opti-mum temperature for degradation is 30815 K The optimumlight intensity is 25mWcm2 at pH 68 The degradationof Anthracene increases with the increase of light intensityNevertheless the increase of light intensity leads to theincrease of the number of electron-hole pairs and increasesthe degradation of Anthracene

Conflict of Interests

The authors declare that there is no conflict of interestsregarding the publication of this paper

Acknowledgments

The authors are gratefully acknowledging the financial sup-port provided by the Arab Science and Technology Founda-tion (ASTF) without which this researchwould not have been

possible The authors also express sincere appreciation to allthe staff working at ASTF Baghdad OfficeThe authors thankDr Amir Hakki for his assistance in the experimental phasesof the research

References

[1] S Ledakowicz J S Miller and D Olejnik ldquoOxidation of PAHsinwater solution by ozone combinedwith ultraviolet radiationrdquoInternational Journal of Photoenergy vol 3 no 2 pp 95ndash1012001

[2] F J Lopez-Jimenez A Ballesteros-Gomez and S RubioldquoDetermination of polycyclic aromatic hydrocarbons (PAH4)in food by vesicular supramolecular solvent-basedmicroextrac-tion and LC-fluorescence detectionrdquo Food Chemistry vol 143pp 341ndash347 2014

[3] M Ciecierska and M W Obiedzinski ldquoPolycyclic aromatichydrocarbons in the bakery chainrdquo Food Chemistry vol 141 no1 pp 1ndash9 2013

[4] T Payanan N Leepipatpiboon and P Varanusupakul ldquoLow-temperature cleanup with solid-phase extraction for the deter-mination of polycyclic aromatic hydrocarbons in edible oilsby reversed phase liquid chromatography with fluorescencedetectionrdquo Food Chemistry vol 141 no 3 pp 2720ndash2726 2013

[5] J Pincemille C Schummer E Heinen and G Moris ldquoDeter-mination of polycyclic aromatic hydrocarbons in smoked andnon smoked black teas and tea infusionrdquo Food Chemistry vol145 pp 807ndash813 2014

[6] A L V Escarrone S S Caldas E B Furlong and V LMenghetti ldquoPolycyclic aromatic hydrocarbons in rice graindried by different processes evaluation of quick easy cheapeffective rugged and safe extraction methodrdquo Food Chemistryvol 146 pp 597ndash602 2014

[7] A M R Machado M G Cardoso H S Dorea et al ldquoCon-tamination of cachaca by PAHs from storage containersrdquo FoodChemistry vol 146 pp 65ndash70 2014

[8] L Zhang P Li Z Gong and A Oni Adeola ldquoPhotochemicalbehavior of benzo[a]pyrene on soil surfaces under UV lightirradiationrdquo Journal of Environmental Sciences vol 18 no 6 pp1226ndash1232 2006

[9] J Ma Y Liu Q Ma C Liu and H He ldquoHeterogeneousphotochemical reaction of ozone with anthracene adsorbed onmineral dustrdquo Atmospheric Environment vol 72 pp 165ndash1702013

[10] R Debestani K J Ellis and M E Sigman ldquoPhotodecomposi-tion of anthracene on dry surfaces products and mechanismrdquoJournal of Photochemistry and Photobiology A Chemistry vol86 no 1ndash3 pp 231ndash239 1995


[11] N A Mir M M Haque A Khan M Muneer and C BoxallldquoPhotoassisted degradation of a herbicide derivative dinosebin aqueous suspension of titaniardquo The Scientific World Journalvol 2012 Article ID 251527 8 pages 2012

[12] F H Hussein ldquoComparison between solar and artificial photo-catalytic decolorization of textile industrial wastewaterrdquo Inter-national Journal of Photoenergy vol 2012 Article ID 793648 10pages 2012

[13] L M Ahmed I Ivanova F H Hussein and D W Bahne-mann ldquoRole of platinum deposited on TiO

2in photocatalytic

methanol oxidation and dehydrogenation reactionsrdquo Interna-tional Journal of Photoenergy vol 2014 Article ID 503516 9pages 2014

[14] F H Hussein ldquoEffect of photocatalytic treatment on physicaland biological properties of textile dyeing wastewaterrdquo AsianJournal of Chemistry vol 25 no 16 pp 9387ndash9392 2013

[15] F H Hussein ldquoChemical properties of treated textile dyeingwastewaterrdquo Asian Journal of Chemistry vol 25 no 16 pp9393ndash9400 2013

[16] F H Hussein and A F Halbus ldquoRapid decolorization ofcobalaminrdquo International Journal of Photoenergy vol 2012Article ID 495435 9 pages 2012

[17] A J Attia S H Kadhim and F H Hussein ldquoPhotocatalyticdegradation of textile dyeing wastewater using titanium dioxideand zinc oxiderdquo E-Journal of Chemistry vol 5 no 2 pp 219ndash223 2008

[18] W-Y Wang A Irawan and Y Ku ldquoPhotocatalytic degradationof Acid Red 4 using a titanium dioxide membrane supportedon a porous ceramic tuberdquo Water Research vol 42 no 19 pp4725ndash4732 2008

[19] L Zhang P Li Z Gong and X Li ldquoPhotocatalytic degradationof polycyclic aromatic hydrocarbons on soil surfaces using TiO

2

under UV lightrdquo Journal of Hazardous Materials vol 158 no 2-3 pp 478ndash484 2008

[20] O T Woo W K Chung K H Wong A T Chow andP K Wong ldquoPhotocatalytic oxidation of polycyclic aromatichydrocarbons intermediates identification and toxicity testingrdquoJournal of Hazardous Materials vol 168 no 2-3 pp 1192ndash11992009

[21] J Gu D Dong L Kong Y Zheng and X Li ldquoPhotocatalyticdegradation of phenanthrene on soil surfaces in the presence ofnanometer anatase TiO

2under UV-lightrdquo Journal of Environ-

mental Sciences vol 24 no 12 pp 2122ndash2126 2012[22] N Vela M Martınez-Menchon G Navarro G Perez-Lucas

and S Navarro ldquoRemoval of polycyclic aromatic hydrocarbons(PAHs) from groundwater by heterogeneous photocatalysisunder natural sunlightrdquo Journal of Photochemistry and Photo-biology A Chemistry vol 232 pp 32ndash40 2012

[23] J Theurich D W Bahnemann R Vogel F E Ehamed GAlhakimi and I Rajab ldquoPhotocatalytic degradation of naph-thalene and anthracene GC-MS analysis of the degradationpathwayrdquo Research on Chemical Intermediates vol 23 no 3 pp247ndash274 1997

[24] S Das M Muneer and K R Gopidas ldquoPhotocatalytic degra-dation of wastewater pollutants Titanium-dioxide-mediatedoxidation of polynuclear aromatic hydrocarbonsrdquo Journal ofPhotochemistry and Photobiology A Chemistry vol 77 no 1 pp83ndash88 1994

[25] N A Laoufi D Tassalit and F Bentahar ldquoThe degradationof phenol in water solution by TiO

2photocatalysis in helical

reactorrdquo Global NEST Journal vol 10 no 3 pp 404ndash418 2008

[26] J S Miller and D Olejnik ldquoPhotolysis of polycyclic aromatichydrocarbons in waterrdquo Water Research vol 35 no 1 pp 233ndash243 2001

[27] Z Luo K Katayama-Hirayama T Akitsu and H KanekoldquoPhotocatalytic degradation of pyrene in porous PtTiO

2-SiO2

photocatalyst suspension under UV irradiationrdquo Nano vol 3no 5 pp 317ndash322 2008

[28] DDong P Li X LiQ Zhao Y Zhang andC Jia ldquoInvestigationon the photocatalytic degradation of pyrene on soil surfacesusing nanometer anatase TiO

2under UV irradiationrdquo Journal

of Hazardous Materials vol 174 no 1ndash3 pp 859ndash863 2010

Submit your manuscripts athttpwwwhindawicom

Hindawi Publishing Corporationhttpwwwhindawicom Volume 2014

Inorganic ChemistryInternational Journal of

Hindawi Publishing Corporation httpwwwhindawicom Volume 2014

International Journal ofPhotoenergy


Carbohydrate Chemistry

International Journal of


Journal of

Chemistry


Advances in

Physical Chemistry

Hindawi Publishing Corporationhttpwwwhindawicom

Analytical Methods in Chemistry

Journal of

Volume 2014

Bioinorganic Chemistry and ApplicationsHindawi Publishing Corporationhttpwwwhindawicom Volume 2014

SpectroscopyInternational Journal of


The Scientific World JournalHindawi Publishing Corporation httpwwwhindawicom Volume 2014

Medicinal ChemistryInternational Journal of


Chromatography Research International


Applied ChemistryJournal of



Theoretical ChemistryJournal of


Journal of

Spectroscopy

Analytical ChemistryInternational Journal of


Journal of


Quantum Chemistry


Organic Chemistry International

ElectrochemistryInternational Journal of



CatalystsJournal of


CB

VB

UV

eminus

h+

O2

O2minus∙

Reduction

H2O∙OHO

O +O2

Oxidation

Scheme 1 Mechanism diagram of photocatalytic degradation for Anthracene

reactions started by hydroxyl radical on the TiO2surface

Recombination for the produced hole from valance band andseparated electron from conductive band it can appear eitherin the volume or on the surface of the semiconductor particleaccompanied with heat releasing To this end both UV lightsource and TiO

2are necessary for photooxidation reaction

to occur [18] The photodegradation of PAHs compounds inwater using TiO

2catalyst has proved high efficiency in [19]

Furthermore many researchers dealt with the PAHs inwater by photocatalytic degradation for TiO

2 Woo et al

in [20] investigated photocatalytically oxidation using TiO2

of 5 selected PAHs namely naphthalene acenaphthylenephenanthrene Anthracene and benzo[a]anthracene Gu etal in [21] studied degradation of phenanthrene on soilsurfaces photocatalytically with the addition of nanopar-ticulate anatase TiO

2under UV-irradiation Vela et al in

[22] discussed photocatalytic processes using semiconductormaterials (ZnO and TiO

2) to remove the residual con-

centrations of several PAHs from groundwater Theurichet al in [23] reported themechanism of the photocatalytictransformation of naphthalene and Anthracene qualitativelyin aqueous suspensions of titanium dioxide Indeed catalystTiO2can play as efficient photocatalyst in the oxidation of

PAHs and convert it to safer compounds especially withAnthracene Fluorene and Naphthalene by artificial or sun-light illumination [19 24] To this end our aim in the presentpaper is to study the effect of photocatalytic reactions onthe degradation of Anthracene using titanium dioxide underdifferent experimental conditions

UV illumination of TiO2yields valence band holes and

conduction band electrons (1) which interactwith the surfaceadsorbedmolecular oxygen to give superoxide radical anionsO2

minus∙ (2) and finally the water produces radicals of HO∙ (3)[25] These radicals oxidize target molecule (Anthracene) toAnthraquinone (4)

TiO2+ ℎ] 997888rarr h+vb + e

minus

cb (1)

eminuscb +O2 997888rarr O2

minus∙ (2)

h+vb + TindashOH2 997888rarr HO∙ads +H+ (3)

HO∙ads + Anthracene 997888rarr Anthraquinone (4)

2 Experimental Procedure

21 Chemicals and Reagents Anthracene was purchasedfrom Sigma Aldrich Germany and used without furtherpurification Acetonitrile (anhydrous ge9998) Dichloro-methane (anhydrousge9998)Acetone ethyl acetate (anhy-drous ge9998) and methanol HPLC-gradient grade werepurchased also from Sigma Aldrich Germany Titaniumdioxide particles were purchased from Degussa (P25)anhydrous Na

2SO4(extra pure Allied Signal Riedel-demdash

Germany)

22 Preparation of Stock Solution of Anthracene A set ofdilutions of Anthracene solution at the concentration of100mgL were made in the following solvents methanoldichloromethane acetonitrile ethyl acetate and acetoneAnthracene solutions in the above solvents were preparedand stored in room temperature (20 plusmn 2∘C) in dark placeto keep it from the light degradation Calibration curvefor Anthracene solution has been achieved by preparationseveral concentrations (01 05 1 2 4 8 16 and 30) mgL Allglassware used for experiments was washed in chromic acidmixture for 12 h with methanol deionized water and acetoneand then dried at 110∘C for 3 h

23 Solid Phase Extraction and Sample Preparation Solidphase extraction (SPE) method was used to extract theAnthracene from the mixture (aqueous solution at differentsolvents) by Supelcoclean ENV-18 solid phase extractiontube After passing the specific volume of aqueous solutionthrough extraction column the extract was treated withanhydrous Na

2SO4to remove all the water content from the

extract and then it was concentrated by rotary evaporator(BUCHI-RE121-Swizerland made) in temperatures below35∘C by water bath (BUCHI 461MetrohmSwiss made) to bein volume 1mLThen sampleswere analyzed byGC2010 (Shi-madzu Japan) The study revealed that the Anthracene levelhad no effect on the percent decrease of the compoundduringevaporation process for the solvent The average recovery ofanalytes for every liquid media and corresponding relativestandard deviations RSD (119899 = 5) were represented in Table 1Chromatographic conditions are listed in Table 2








119862

119905= 119862

0sdot 119890

minus119896119905 (5)

or

ln(119862

0

119862

119905

) = 119896119905 (6)






ln C

0C

t

0123456789

0 30 60 90 120 150 180 210Time (min)

25ppm10ppm ppm1

ppm5




00005

0010015

0020025

0030035

0040045

005


k(m

inminus1)


0

1

2

3

445

35

25

15

05

5

0 30 60 90 120 150 180 210Time (min)

ln C

0C

t

30815K29815K

28815K27815K





31 32 33 34 35 36 370

minus1

minus2

minus3

minus4

minus5

ln k

(1000T) (K)



2at (27815ndash30815) K

Time (min)

ln C

0C

t

10

9

8

7

6

5

4

3

2

1

0

0 30 60 90 120 150 180 210

1mWcm2

15mWcm2

20mWcm2

25mWcm2


00 05 1 15 2 25 3

0005001

0015002

0025003

0035004

0045005

k(m

inminus1)



25

50

75

00

TIC15205 (1217)18015 (1245)

25 50 75 100 125 150 175 200 225 250

(times1000000)


()

1500 1750 2000 2250 2500 2750 3000 3250 3500

0

50

100138

170

302217 310253 280 323 334 346


25 50 75 100 125 150 175 200 225 250

TIC

05

10

(times10000000)


()

1500 1750 2000 2250 2500 2750 3000 3250 3500

0

50

100 137

160

244 274207 296 310324 333 346







O O





4 Conclusions




Acknowledgments



References















2in photocatalytic








2














2-SiO2














Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of








119862

119905= 119862

0sdot 119890

minus119896119905 (5)

or

ln(119862

0

119862

119905

) = 119896119905 (6)






ln C

0C

t

0123456789

0 30 60 90 120 150 180 210Time (min)

25ppm10ppm ppm1

ppm5




00005

0010015

0020025

0030035

0040045

005


k(m

inminus1)


0

1

2

3

445

35

25

15

05

5

0 30 60 90 120 150 180 210Time (min)

ln C

0C

t

30815K29815K

28815K27815K





31 32 33 34 35 36 370

minus1

minus2

minus3

minus4

minus5

ln k

(1000T) (K)



2at (27815ndash30815) K

Time (min)

ln C

0C

t

10

9

8

7

6

5

4

3

2

1

0

0 30 60 90 120 150 180 210

1mWcm2

15mWcm2

20mWcm2

25mWcm2


00 05 1 15 2 25 3

0005001

0015002

0025003

0035004

0045005

k(m

inminus1)



25

50

75

00

TIC15205 (1217)18015 (1245)

25 50 75 100 125 150 175 200 225 250

(times1000000)


()

1500 1750 2000 2250 2500 2750 3000 3250 3500

0

50

100138

170

302217 310253 280 323 334 346


25 50 75 100 125 150 175 200 225 250

TIC

05

10

(times10000000)


()

1500 1750 2000 2250 2500 2750 3000 3250 3500

0

50

100 137

160

244 274207 296 310324 333 346







O O





4 Conclusions




Acknowledgments



References















2in photocatalytic








2














2-SiO2














Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


31 32 33 34 35 36 370

minus1

minus2

minus3

minus4

minus5

ln k

(1000T) (K)



2at (27815ndash30815) K

Time (min)

ln C

0C

t

10

9

8

7

6

5

4

3

2

1

0

0 30 60 90 120 150 180 210

1mWcm2

15mWcm2

20mWcm2

25mWcm2


00 05 1 15 2 25 3

0005001

0015002

0025003

0035004

0045005

k(m

inminus1)



25

50

75

00

TIC15205 (1217)18015 (1245)

25 50 75 100 125 150 175 200 225 250

(times1000000)


()

1500 1750 2000 2250 2500 2750 3000 3250 3500

0

50

100138

170

302217 310253 280 323 334 346


25 50 75 100 125 150 175 200 225 250

TIC

05

10

(times10000000)


()

1500 1750 2000 2250 2500 2750 3000 3250 3500

0

50

100 137

160

244 274207 296 310324 333 346







O O





4 Conclusions




Acknowledgments



References















2in photocatalytic








2














2-SiO2














Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of


O O





4 Conclusions




Acknowledgments



References















2in photocatalytic








2














2-SiO2














Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of





2in photocatalytic








2














2-SiO2














Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of










Journal of

Chemistry


Advances in

Physical Chemistry



Journal of

Volume 2014














Journal of

Spectroscopy



Journal of


Quantum Chemistry






CatalystsJournal of

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