Qin Qing-Dong, Ma Jun, Liu Ke, Yang Yi-Xin
School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Huan Jing Ke Xue. 2007 Apr;28(4):766-71.
Degradation of nitrobenzene by ozone/zeolite process was investigated in a continuous flow reactor. The results showed that nitrobenzene was degraded by ozone/zeolite process efficiently in comparison to ozone alone. The removal of nitrobenzene was 100% in 7 minutes. The reaction followed pseudo-first-order kinetics. By investigating the effect of scavenger on nitrobenzene removal, it is concluded that nitrobenzene was mainly degraded by hydroxyl radicals in solution. Increasing zeolite dosage and ozone concentration also enhanced nitrobenzene removal. However, there was an optimum removal rate among zeolite dosages. The relationship between the ozone concentrations and the kinetic constants was linear. At the same time, nitrobenzene decomposition was independent of influent nitrobenzene concentration during ozone/zeolite process. Additionally, the degradation rate of ozone/zeolite process was inhibited significantly by increasing ionic strength. When the ionic strength concentration increased from 0 to 1 x 10(-3) mol/L, the removal of nitrobenzene by ozone/zeolite process decreased from 81.2% to 31.6% correspondingly. pH mainly affected the decomposition rate of ozone. As pH decreased, the degradation rate of nitrobenzene by ozone/zeolite process decreased too. Zeolite had a relatively longer lifetime.
在连续流反应器中研究了臭氧/沸石工艺对硝基苯的降解。结果表明，与单独使用臭氧相比，臭氧/沸石工艺能有效降解硝基苯。7分钟内硝基苯的去除率达100%。该反应遵循准一级动力学。通过研究清除剂对硝基苯去除的影响，得出硝基苯主要在溶液中被羟基自由基降解的结论。增加沸石用量和臭氧浓度也能提高硝基苯的去除率。然而，在不同的沸石用量中存在一个最佳去除率。臭氧浓度与动力学常数之间呈线性关系。同时，在臭氧/沸石工艺中，硝基苯的分解与进水硝基苯浓度无关。此外，增加离子强度会显著抑制臭氧/沸石工艺的降解速率。当离子强度浓度从0增加到1×10⁻³mol/L时，臭氧/沸石工艺对硝基苯的去除率相应地从81.2%降至31.6%。pH主要影响臭氧的分解速率。随着pH降低，臭氧/沸石工艺对硝基苯的降解速率也降低。沸石具有相对较长的使用寿命。
