类芬顿铁基双金属催化过硫酸盐降解苯胺

Degradation of aniline with persulfate catalyzed by Feton-like iron-based bimetallic catalysts

为了考察类芬顿铁基双金属催化剂催化过硫酸盐降解污染物的效能,以苯胺作为目标污染物,研究了催化剂质量浓度、过硫酸钠质量浓度、pH值和反应时间等因素对苯胺降解的影响规律,并利用紫外光谱检测苯胺降解中特征峰的变化,初步探讨苯胺降解机理。试验结果表明,苯胺去除率随着氧化剂和催化剂质量浓度的增加而提高;随着反应时间的延长而提高;随着pH值增加先增大后减小,并在pH=6时去除率最佳。对比苯胺降解前后的紫外光谱图可知,降解之后的苯胺在波长为545 nm处的特征吸收峰几乎消失,说明苯胺基本降解完全,最终转化为小分子物质CO_2和H_2O。当催化剂质量浓度为0.1 g/L,氧化剂质量浓度为0.1 g/L,pH=6,反应时间达到20 min时,5 mg/L的苯胺废水经过催化氧化后质量浓度低于0.03 mg/L,达到国家标准规定的苯胺排放值以下。

Aniline is used as the target pollutant to investigate the effect of Fe-based bimetallic catalysts on the degradation of pollutants. The effects of the dosages of catalyst and persulfate, pH value and re- action time on aniline degradation are studied. The degradation mechanism of aniline is discussed by UV detection. The experimental results show that the removal rate of aniline increases with the in- crease of the oxidant, catalyst, and reaction time. Besides, the removal rate of aniline increases first and then decreases with increase of pH value, and the removal rate is the best at pH 6. Comparing the UV spectra before and after degradation, the characteristic absorption peaks of the aniline at the wave- length of 545 nm disappeared, indicating that the aniline is completely degraded and converted into small molecules of CO2 and H2O. The results show that when the dosage of catalyst is 0.1 g/L, the dos- age of oxidant is 0.1 g/L, pH value of 6 and the reaction time is above 20 min, the concentration of 5 mg/L aniline wastewater can reach the national standard law below the discharge value of 0.03 mg/L.