摘要
选用 2 5 3 7nm的紫外光为激发光源 ,对品红 /过氧化氢体系中的紫外光解离进行了研究 .结果表明 ,该体系中品红的解离近似为表观一级反应 ,解离反应的速率常数为 0 0 386 7s- 1.品红水溶液的脉冲瞬态光谱结果表明 ,品红主要与OH自由基反应而导致脱色 ,其在 5 4 0nm处的脱色与 34 0nm处的瞬态吸收存在很好的相关性 ,品红在5 4 0nm处脱色为一级反应 ,速率常数为 8 1 0× 1 0 5s- 1,34 0nm处新的瞬态物种生成较快而衰减较慢 ,其衰减速率为 5 33× 1 0 3 s- 1.
The photolysis at 253.7nm UV of fuchsine /hydrogen peroxide is researched by such analysis method as UV-VIS spectrum,pulse transient spectrum,etc.Experiment results indicate that the degradation dynamics of fuchsine at 253.7nm UV/H 2O 2 is approxiately 1 st order reaction.The rate constant is 0.03867s -1. Pulse transient spectrum indicates that fuchsine decourizes mainly for its reaction with hydroxyl radical.The decourization in 540nmm has good relativity with the transient absorbance in 340nm.Fuchsine decolourization in 540nm is fitted 1 st order reaction,the rate constant is 8.10×10 5s -1.New transient kind produces faster,and falls slower,its slow falling rate constant is 5.33×10 3s -1.The mechanism of fuchsine degradation by UV/H 2O 2 is discussed.
出处
《环境化学》
CAS
CSCD
北大核心
2002年第4期344-348,共5页
Environmental Chemistry
