Heterogeneous Photocatalytic Degradation Kinetic of Gaseous Ammonia Over Nano-TiO2 Supported on Late

• 作 者: QI-JIN GENG XI-KUI WANG SHAN-F
• 机 构: Department of Chemistry,College of Chemistry and Chemical Engineering,The People's Hospital of Weif
• 出 处: 生物医学与环境科学（英文版）
• 发表日期: 2004年期
• 关键词: TiO2 Gaseous ammonia Latex paint Photocatalytic degradation Kinetic in static st

Objective To investigate the photoeatalytic degradation of gaseous ammonia in static state by using nano-TiO2 as photocatalyst supported on latex paint film under UV-irradiation.Methods Experiments were conducted to study the relationship between the initial concentration of ammonia and the degradation products competing to be adsorbed on catalyst surface.Degradation of ammonia and its products were detected by spectrophotometry and catalytic kinetic spectrophotometry,respectively.Results On the one hand,TiO2 catalyst was excellent for degradation of ammonia,and the crystal phase of TiO2,anatase or rutile,had little effect on degradation of ammonia,but the conversion of ammonia grew with the increase of catalyst content.On the other hand,apparent rate constant and conversion of anmaoma decreased with the increase of initial concentration of ammonia,and the photocatalytic degradation reaction followed a pseudo-first-order expression due to the evidence of linear correlation between-lnC/Co vs.irradiation time t, but the relationship between initial concentration and the degradation products Was not linear in low initial concentration.Conclusion Whether the photocatalytic degradation of ammonia in static state follows a first-order reaction depends on the initial ammonia concentration due to competition in adsorption between reactant and the degradation products.