title: Laser enhanced photo-catalytic removal of phenol from water using p-type NiO semiconductor catalyst.
abstract: Phenol is a carcinogen to humans and is a serious health concern, even at low concentrations. The efficient removal of phenol inside waste water is highly desirable. Laser induced photo-catalysis has been applied for removal of phenol from waste water using p-type NiO semiconductor catalyst for the first time. The characteristics of phenol removal using laser induced photo-catalytic process were investigated. The dependence of phenol removal on laser energy (100-250 mJ) and laser irradiation time (0-60 min) was studied. The rate of phenol removal process was characterized using UV absorption spectrometry, Raman spectroscopy and gas chromatography. In addition, the role of pH changes during the removal process was also investigated. Laser induced photo-catalytic process is highly efficient in removal of phenol in water over a short period of time (in minutes) as compared to conventional methods using lamps (hours). The phenol removal process pursued the first order kinetics with decay constant=0.0125 min(-1).
authors.affiliation: Laser Research Laboratory, Physics Department, King Fahd University of Petroleum & Minerals, Box 5047, Dhahran 31261, Saudi Arabia. magondal@kfupm.edu.sa
authors.forename: M A
authors.initials: MA
authors.lastname: Gondal
authors.forename: M N
authors.initials: MN
authors.lastname: Sayeed
authors.forename: Z
authors.initials: Z
authors.lastname: Seddigi
mesh_terms: D002384:Catalysis; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D007834:Lasers; D009532:Nickel / Q000737:chemistry*; D019800:Phenol / Q000737:chemistry / Q000528:radiation effects; D010777:Photochemistry; D014865:Waste Disposal, Fluid / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000737:chemistry / Q000528:radiation effects
chemical_list: D014874:Water Pollutants, Chemical; D019800:Phenol; D009532:Nickel; C028007:nickel monoxide