Yang Yi-xin, Ma Jun, Qin Qing-dong, Zhao Lei, Wang Sheng-jun, Zhang Jing
School of Municipal and Environmental Engineering, Harbin Institute of Technology, Harbin 150090, China.
Huan Jing Ke Xue. 2006 Oct;27(10):2028-34.
Nanosized TiO2 catalyzed ozonation of trace nitrobenzene in water was carried out in an agitated slurry semi-batch. It demonstrated that removal rate of nitrobenzene with catalytic ozonation increased by 44% than ozonation alone. Effect of heat treatments of TiO2, catalyst mass, the initial concentration of ozone and nitrobenzene, and pH were investigated respectively. TiO2 calcined at 550 degrees C showed the best catalytic activity. In the presence of TiO2 calcined at 550 degrees C, about 56.57% of nitrobenzene in the solution could be ozonated. Both ozone dosage and initial concentration of nitrobenzene exerted a positive influence on the catalytic ozonation. But the increase of the catalyst mass did not yield any significant increase of the nitrobenzene removal. The efficiency of catalytic ozonation was special lower at acid pH than basic pH. It was also observed that both ozonation and catalytic ozonation were significantly influenced by tert-butyl alcohol, which testified that nanosized TiO2 catalyzed ozonation of nitrobenzene follows a radicaltype mechanism.
在搅拌淤浆半间歇式反应器中进行了纳米二氧化钛催化臭氧化水中痕量硝基苯的实验。结果表明，催化臭氧化对硝基苯的去除率比单独臭氧化提高了44%。分别考察了二氧化钛的热处理、催化剂用量、臭氧和硝基苯的初始浓度以及pH值的影响。在550℃煅烧的二氧化钛表现出最佳的催化活性。在550℃煅烧的二氧化钛存在下，溶液中约56.57%的硝基苯可被臭氧化。臭氧用量和硝基苯的初始浓度对催化臭氧化均有积极影响。但催化剂用量的增加并未使硝基苯的去除率显著提高。催化臭氧化在酸性pH值下的效率特别低于碱性pH值。还观察到，叔丁醇对臭氧化和催化臭氧化均有显著影响，这证明纳米二氧化钛催化臭氧化硝基苯遵循自由基型机理。
