1. 1. 2. 3. © Laser-Enhanced Photocatalytic Degradation Of Organic Pollutants From Water Using ZnO Semiconductor Catalyst Gondal, MA; Sayeed, MN TAYLOR FRANCIS INC, JOURNAL OF ENVIRONMENTAL SCIENCE AND HEALTH PART A-TOXIC/HAZARDOUS SUBSTANCES ENVIRONMENTAL ENGINEERING; pp: 70-77; Vol: 43 King Fahd University of Petroleum & Minerals http://www.kfupm.edu.sa Summary Wastewater contaminated with organic pollutants creates serious environmental problems. Laser induced photocatalysis has been investigated for removal of organic pollutant like phenol from water. The important mechanism for degradation of phenol by UV laser irradiation is redox reactions triggered by semiconductor catalyst in presence of water. In this study the potential of a ZnO semiconductor catalyst has been explored as an effective catalyst for the photodegradation of phenol using a Nd:YAG laser-emitting at 355 nm in UV-radiation in a batch reactor. The influences of different parameters such as catalyst concentration, UV-radiation intensity, and pH on the extent of photo degradation have been investigated. Overall degradation of phenol achieved was 70% after 60 minutes of laser irradiation of 100 ppm phenol solution in water. The reaction rate constant fit a first-order reaction model for phenol degradation and was estimated as 0.0088 min(-1). This study proved that laser induced photocatalytic removal of phenol is highly efficient as compared with the broadband spectral sources such as lamps being applied in majority of setups worldwide. References: *CDC, 1976, DHEW PUBL AKSU Z, 2005, REV PROCESS BIOCH, V40, P997 BEHNAJADY MA, 2006, J HAZARD MATER, V133, P226, DOI Copyright: King Fahd University of Petroleum & Minerals; http://www.kfupm.edu.sa

2. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. 19. 20. © 10.1016/j.hazmat.2005.10.022 BERTONCINI C, 2003, CARBON, V41, P1101, DOI 10.1016/S0008-6223(03)00015-0 BRANDT S, 1997, BIOTECHNOL BIOENG, V55, P480 DENIZLI A, 2004, PROCESS BIOCHEM, V39, P2025, DOI 10.1016/j.procbio.2003.10.003 DENIZLI A, 2005, BIORESOURCE TECHNOL, V96, P59, DOI 10.1016/j.biortech.2003.11.029 GONDAL MA, 2004, APPL CATAL A-GEN, V268, P159, DOI 10.1016/j.apcata.2004.03.030 GONDAL MA, 2004, CHEM PHYS LETT, V385, P111, DOI 10.1016/j.cplett.2003.12.066 GONDAL MA, 2004, CHEM PHYS LETT, V392, P372, DOI 10.1016/j.cplett.2004.05.092 GONDAL MA, 2004, J MOL CATAL A-CHEM, V222, P259, DOI 10.1016/j.molcata.2004.08.022 GONDAL MA, 2005, ENERG SOURCE, V27, P1151, DOI 10.1080/00908310490479574 21. GRZECHULSKA J, 2002, APPL CATAL B-ENVIRON, V36, P45 22. HAMEED A, 2004, J MOL CATAL A-CHEM, V219, P109, DOI 23. 10.1016/j.molcata.2004.04.042 24. HAMEED A, 2005, J MOL CATAL A-CHEM, V227, P241, DOI 25. 10.1016/j.molcata.2004.10.053 26. HAMEED A, 2005, J MOL CATAL A-CHEM, V233, P35, DOI 27. 10.1016/j.molcata.2005.02.009 28. HERRMANN JM, 2005, TOP CATAL, V34, P49, DOI 10.1007/s11244-005- 3788-2 29. KAWAGUCHI H, 1993, ENVIRON TECHNOL, V14, P289 30. KHALID M, 2004, IND ENG CHEM RES, V43, P5275, DOI 10.1021/ie0400447 31. LI LS, 2006, J HAZARD MATER, V128, P145, DOI 32. 10.1016/j.jhazmat.2005.07.050 33. LING CM, 2004, CHEMOSPHERE, V57, P547, DOI 34. 10.1016/j.chemosphere.2004.07.011 35. MACHADO AEH, 2003, J PHOTOCH PHOTOBIO A, V155, P231 36. MINSKER KS, 2001, THEOR FOUND CHEM ENG, V35, P162 37. MUNAF E, 1997, ENVIRON TECHNOL, V18, P355 38. OKUYA M, 2002, SOL ENERG MAT SOL C, V70, P425 39. OLLIS DF, 1991, ENVIRON SCI TECHNOL, V25, P1522 40. SAKTHIVEL S, 2002, J PHOTOCH PHOTOBIO A, V148, P283 41. SALAICES M, 2004, CHEM ENG SCI, V59, P3, DOI 10.1016/j.ces.2003.07.015 42. SCHIAVELLO M, 1987, NATO ASI SER C-MATH, P238 43. SENEL S, 2006, J HAZARD MATER, V138, P317, DOI 44. 10.1016/j.jhazmat.2006.05.121 Copyright: King Fahd University of Petroleum & Minerals; http://www.kfupm.edu.sa

3. 45. 46. 47. 48. © SLEIN MW, 1980, DEGRADATION CHEM CAR YAHAYA H, 2004, CHEM PHYS LETT, V400, P206 YUN CY, 2002, APPL SURF SCI, V200, P239 ZHAN HQ, 1998, DYES PIGMENTS, V37, P231 For pre-prints please write to: magondal@kfupm.edu.sa Copyright: King Fahd University of Petroleum & Minerals; http://www.kfupm.edu.sa