Degradation kinetics and mechanism of aniline by heat-assisted persulfate oxidation

• Published in: Journal of environmental sciences (China) 2012-05, Vol.24 (5), p.821-826
• Main Authors: Xie, Xiaofang, Zhang, Yongqing, Huang, Weilin, Huang, Shaobing
• Format: Article
• Language: English
• Subjects: alkalinity; aniline; Aniline Compounds - chemistry; aqueous solutions; Chromatography, High Pressure Liquid; Hot Temperature; Hydrogen-Ion Concentration; kinetic; Kinetics; liquid chromatography; Mass Spectrometry; mechanism; Minerals - chemistry; oxidation; Oxidation-Reduction; persulfate; pH值; Solutions; Sulfates - chemistry; Temperature; 反应动力学; 氧化降解; 水溶液; 苯胺; 过硫酸钾氧化; 降解机制; 降解率
• ISSN: 1001-0742; 1878-7320
• DOI: 10.1016/S1001-0742(11)60844-9

Oxidation of aniline by persulfate in aqueous solutions was investigated and the reaction kinetic rates under different temperature, persulfate concentration and pH conditions were examined in batch experiments. The results showed that, the aniline degradation followed pseudo first-order reaction model. Aniline degradation rate increased with increasing temperature or persulfate concentration. In the pH range of 3 to 11, a low aniline degradation rate was obtained at strong acid system (pH 3), while a high degradation rate was achieved at strong alkalinity (pH 11). Maximum aniline degradation occurred at pH 7 when the solution was in a weak level of acid and alkalinity (pH 5, 7 and 9). Produced intermediates during the oxidation process were identified using liquid chromatography-mass spectrometry technology. And nitrobenzene, 4-4′-diaminodiphenyl and 1-hydroxy-1,2-diphenylhydrazine have been identified as the major intermediates of aniline oxidation by persulfate and the degradation mechanism of aniline was also tentatively proposed.