A bimetallic catalyst, Co-Mn oxide (CoMnOx), was prepared via sol-gel method to activate peroxymonosulfate (PMS) to produce oxygen species for degradation of acid orange 7 (AO7). The effects of CoMnOxdosage, PMS dosage, AO7 dosage, and initial pH on removal efficiency of AO7 were investigated. The experimental results indicated that high CoMnOx and PMS dosage had a prominent impact on the degradation of AO7, weak acid initial pH condition enhance the degradation efficiency, but the increasing of AO7 dosage had anopposite effect, the degradation rate of AO7 could reach 95.28％ under the best reaction condition. By adding different radical scavengers: ethylalcohol (EA) and tertbutylalcohol (TBA), the oxygen species were identified as sulfate radical (SO4-·) and hydroxyl radical (OH·)in which SO4-·made the predominant contribution. The catalyst was characterized by X-ray photoelectron spectroscopy (XPS), X-ray diffraction (XRD). The results showed that the major component of the CoMnOx catalyst was MnCo2O4, in which the mole percentage of Co2+, Co3+, Mn2+, Mn3+, lattice oxygen and surface hydroxyl oxygen were 27.94％, 6.16％, 11.42％, 19.99％, 25.99％, 8.68％.%为了研究CoMnOx在常温下活化过硫酸氢钾(PMS)产生硫酸根自由基(SO4-·)降解酸性偶氮染料酸性橙7(AO7)的效能,采用溶胶-凝胶法制备CoMnOx双金属催化剂,考察了CoMnOx投量、PMS投量、AO7初始浓度以及初始pH对PMS/CoMnOx体系降解AO7效果的影响.结果显示,CoMnOx和PMS投量的增加对AO7的去除率均有提升效果,而随着AO7初始浓度的增加,PMS/CoMnOx体系对其的去除率逐渐降低,在最优条件下反应20min后AO7的去除率达95.28％,较单金属催化效果提升显著,体系初始pH值对AO7降解有显著影响,弱酸性条件下有利于CoMnOx催化PMS氧化反应的进行.通过投加乙醇和叔丁醇两种不同种类的猝灭剂,证实了AO7的降解主要是SO4-·和·OH共同作用的结果,其中SO4-·起主导作用.利用X射线衍射(XRD)、X射线光电子能谱(XPS)对催化剂进行表征,结果表明催化剂的主要存在形式为MnCo2O4其中Co2+、Co3+、Mn2+、Mn3+、晶格氧、羟基氧的物质的量百分比分别为27.94％、6.16％、11.42％、19.99％、25.99％、8.68％.
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