【摘要】 在253.7nm紫外光作用下,研究纳米TiO2光催化氧化流动态甲醇的机制,结果表明,甲醇的光催化降解不受水汽的影响,只受氧气含量的影响.在不含氧气的情况下,即使有足量的水汽,甲醇都不会有明显的降解.TiO2受光诱导生成空穴-电子对后,空穴直接氧化甲醇,生成的甲醇正离子在氧气作用下进一步被氧化,形成各种氧化产物.甲醇氧化过程是多通道反应,宏观表现为准一级反应.空气和氧气条件下甲醇的总降解速率常数分别为9.78×10-3和1.79×10-2s-1.更多还原

【Abstract】 Nano TiO2 photocatalytic decomposition of flow gas-phase methanol was investigated under 253.7 nm UV light.The result indicated that oxygen content exerted a significant influence on methanol photocatalytic decomposition.In the absence of oxygen,there was no distinct decomposition even with abundant water vapor.It was concluded that after hole-electron pairs were induced by ultraviolet light,the hole then oxidized methanol directly,forming methanol free radical cation,which would be further oxidized in the presence of oxygen.Methanol oxidation process was a multi-path reaction,and in macro view a pseudo-first-order reaction with decomposition rate constant of 9.78×10-3 s-1 in the presence of air and 1.79×10-2 s-1 in the presence of oxygen.更多还原