ClO_2气相氧化NO和SO_2的特性及反应机理

Research on gas-phase oxidation properties of ClO_2 on NO and SO_2

考察了ClO_2气相氧化NO和SO_2的特性,并对反应机理进行了分析,结果表明:在气相无水条件下,SO_2几乎不被ClO_2氧化,而对NO表现出较强的氧化性能,在温度30℃,n(ClO_2)/n(NO)=1,停留时间5 s条件下,NO氧化率可高于90%;当气相中水分大于0.45%后,ClO_2气相氧化NO的反应历程基本不发生改变,但SO_2将被优先氧化,即ClO_2对SO_2和NO的氧化能力发生了反置。在30~150℃范围内,升高温度将使得NO和SO_2氧化率显著下降,超过150℃后,氧化率下降幅度变缓。气相中氧含量增加使SO_2氧化率下降,对NO氧化率的影响不显著。

The oxidation properties of gas-phase ClO_2 on NO and were investigated. The results showed that SO_2 was barely oxidized by ClO_2 under gas-phase and anhydrous conditions,while NO was easily oxidized under the same conditions. NO oxidation efficiency was higher than 90% under the following conditions： 30 ℃,ClO_2/NO（ mol / mol） = 1,and residence time = 5 s. The mechanism of the gas-phase oxidation of NO by ClO_2 did not change and SO_2 was preferentially oxidized by ClO_2 providing that the H2 O content in the gas phase was greater than 0. 45%,at which point the oxidation selectivity of ClO_2 toward SO_2and NO was reversed. The oxidation efficiency of ClO_2 on SO_2and NO decreased significantly with an increase in the temperature from 30°C to 150°C and decreased slowly at temperatures higher than 150 ℃. The increase in the oxygen content had a negative impact on the SO_2 oxidation efficiency,but had no significant effect on the NO oxidation efficiency.