Page - 86 - in Advanced Chemical Kinetics

ofH2O2wasexposed toUVirradiation,while another set of experimentswas freeofH2O2 to calculate kUV. The concentration ofH2O2waskept higher for ensuringproductionof efficient •OHwithUV-photocatalysis. Figure 2 showsdegradation curves for BZF and p-CBA, bothBZFand p-CBAwere found to follow pseudo-first order degradation kinetics. The second order rate constant of •OHwith p-CBAis5.0 109M 1s 1 [20].Bysubstitutingpseudo-firstorderdegradationconstants(kUV=H2O2 and kUV) values in Eq. (15), the bimolecular rate constant of •OHwith BZFwas calculated and foundout tobe5.66 109M 1s 1. 3.Conclusions Theoverall conclusionof this chapter is that, in radiation chemistry tohaveagoodknowledge about the mechanism of a reactionmechanism it is necessary that one must have sufficient understanding about the free radical kinetics. In addition, competition kineticsmodel can be successfulappliedforthedeterminationofunknownrateconstantsofreactivespecieswithsolute molecule.Thecompetitionkineticscannotonlybeappliedfor●OHrateconstantswiththesolute butalsoformeasurementofeaq and●Hwiththetargetspecies.Thecompetitionkineticsmethod isvalidatedby takingciprofloxacin,norfloxacinandbezafibrateas example compounds.How- ever, itshouldbemakesurethatcompetingreactionsdonotdisobeythekineticsrules. Authordetails MurtazaSayed1*,LuqmanAliShah1, JavedAliKhan1,NoorS.Shah1,2,RozinaKhattak3and HasanM.Khan1 *Addressall correspondence to:murtazasayed_407@yahoo.com 1 RadiationandEnvironmentalChemistryLaboratory,NationalCentreofExcellence in PhysicalChemistry,UniversityofPeshawar,Pakistan 2 DepartmentofEnvironmentalSciences,COMSATSInstituteof InformationTechnology, Vehari,Pakistan 3 DepartmentofChemistry,ShaheedBenazirBhuttoWomenUniversity,Peshawar,Pakistan References [1] Spinks JWT,Woods RJ. An Introduction to RadiationChemistry. John-Wiley and Sons, Inc.,NewYork;1990. [2] FrickeH,HartEJ.Chemicaldosimetry. In:RadiationDosimetry2.AcademicPress,New York;1966.pp.167-239 Advanced Chemical Kinetics86