纳米铁酸铜催化剂活化过一硫酸盐降解苯胺废水

Aniline wastewater degradation by nano copper ferrite catalyst activated peroxymonosulfate

使用溶胶凝胶法制备纳米铁酸铜催化剂,并用于活化过一硫酸盐催化降解苯胺废水。探究了纳米铁酸铜投加量、过一硫酸盐投加量和pH对苯胺降解率的影响。结果表明,在纳米铁酸铜投加量为2.0g/L、过一硫酸盐投加量为0.2g/L、pH=7.0的条件下,纳米铁酸铜活化过一硫酸盐催化降解苯胺废水的效果最好,反应60min,100mL质量浓度为10mg/L的苯胺降解率可达99%。纳米铁酸铜在反应过程中的总铁溶出量仅为0.87mg/L,总铜溶出量仅为0.03mg/L。苯胺的降解途径:一是苯胺中的氨基被自由基攻击,生成亚硝基苯,继续氧化生成硝基苯,然后开环矿化为CO_2和H_2O;二是氨基对位苯环上的氢原子被羟基取代生成对羟基苯胺,对羟基苯胺被自由基攻击生成亚氨基苯醌,进一步反应生成对苯醌,然后开环矿化为CO_2和H_2O。

Nano copper ferrite catalyst was fabricated using sol-gel method and applied for activation peroxymonosulfate to degrade aniline.The key parameters including catalyst dosage,peroxymonosulfate dosage and pH were optimized.Results showed that the degradation rate of aniline could reach optimal(99%)under the catalyst dosage of 2.0 g/L,permonosulfate dosage of 0.2 g/L,and pH of 7.0 within 60 min for 100 mL 10 mg/L aniline wasterwater.The total iron releasing of catalyst was only 0.87 mg/L,and the total copper releasing 0.03 mg/L.The possible transformation pathway were proposed:amino group was attacked by radicals and turned into nitrosobenzene,and then oxidized into nitrobenzene;hydrogen in para-position of amino group was replaced by hydroxyl,then turned into iminophenone and benzoquinone;finally,nitrobenzene and benzoquinone were degraded into CO2 and H2O.