改性活性炭强化催化臭氧氧化降解草酸

对工业活性炭进行酸预处理、硝基化和氨基化表面改性，并在半连续反应器中研究其催化臭氧氧化降解草酸的活性. 结果表明，酸预处理的活性炭比表面积、等电点pH值(pHpzc)和碱性官能团含量提高了5%~10%，但催化降解草酸效率降低15.6%，氨基化活性炭的pHpzc和碱性官能团含量分别由2.6和234.8 mmol/g升至7.0和764.5 mmol/g，而硝基化活性炭的pHpzc和表面碱性官能团含量均降低. 在中性和酸性溶液中，两种改性活性炭降解草酸的活性均高于预处理活性炭. 在pH=7的溶液中，氨基化活性炭在45 min内催化降解草酸降解率为42.4%. 加入叔丁醇会抑制活性炭催化降解草酸，活性炭催化臭氧氧化草酸主要是羟基自由基起作用.

Enhanced Catalytic Ozonation of Oxalic Acid over Modified Activated Carbon

Industrial activated carbon(AC) was pretreated by acid solution and modified by nitration and amination.Its catalytic performance was investigated in a semi-batch reactor.After the acid pretreatment,the specific surface area,pHpzc and content of basic groups of AC were increased about 5%～10%,but its catalytic activity decreased 15.6%.The pHpzc and content of basic functional groups on the surface of AC-NH2 were increased from 2.6 and 234.8 mmol/g to 7.0 and 764.5 mmol/g,respectively.But all of them decreased after nitration.The modified AC samples were more active than the original AC and acid pretreated AC in the catalytic ozonation of oxalic acid at acid and neutral conditions.The degradation rate of AC-NH2 catalytic ozonation of oxalic acid was 42.4% in 45 min in the solution at pH=7.Catalytic ozonation of oxalic acid was inhabited by adding tert-butanol.This indicated that the modified activated carbon catalytic ozonation followed the hydroxyl radical reaction mechanism.