Kinetics of the Oxidation of Hydrogen Sulfide by Atmospheric Oxygen in an Aqueous Medium

作     者：Deepak Singh Rathore Vimlesh Kumar Meena Chandra Pal Singh Chandel Krishna Swarup Gupta 

作者机构：Atmospheric Chemistry LaboratoryDepartment of ChemistryUniversity of RajasthanJaipur302004India 

出 版 物：《Journal of Atmospheric Science Research》 (大气科学研究（英文）)

年 卷 期：2021年第4卷第3期

页      面：46-59页

学科分类：081704[工学-应用化学] 07[理学] 070304[理学-物理化学(含∶化学物理)] 08[工学] 0817[工学-化学工程与技术] 0703[理学-化学] 

主　　题：Hydrogen sulfide Oxygen Oxidation Kinetics Effect of organics 

摘      要：Hydrogen sulfide is an important acid rain precursor and this led us to investigate the kinetics of its oxidation in aqueous phase by atmospheric *** kinetics was followed by measuring the depletion of oxygen in a *** reaction was studied under pseudo order conditions with[H2S]in *** kinetics followed the rate law:-d[O_(2)]/dt=k[S][O_(2)]_(t)(A)Where[S]represents the total concentration of hydrogen sulfide,[O_(2)]_(t)is the concentration of oxygen at time t and k is the second order rate *** equilibria(B-C)govern the dissolution of H_(2)S;the sulfide ion in water forms different species:H_(2)S K1→←HS^(-)+H_(+)(B)HS^(-)K2→←S^(2-)+H^(+)(C)Where K_(1)and K_(2)are first and second dissociation constants of H_(2)***,H_(2)S is present as undissociated H_(2)S,HS^(-)and S^(2-)ions,nature of[H^(+)]dependence of reaction rate required only HS^(-)to be reactive and *** rate law(A)on including[H^(+)]dependence became Equation(D).-d[O_(2)]/dt=k_(1)K_(1)[H^(+)][S][O_(2)]_(t)/([H^(+)]^(2)+K_(1)[H^(+)]+K_(1)K_(2))(D)Our results indicate anthropogenic VOCs such as acetanilide,benzene,ethanol,aniline,toluene,benzamide,o-xylene,m-xylene,p-xylene and anisole to have no significant effect on the reaction rate and any observed small effect is within the uncertainty of the rate measurements.