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采用碳纳米管(CNT)活化过一硫酸盐(PMS)的方法产生自由基,研究氯离子(Cl-)对 CNT/PMS 体系氧化降解金橙 G(OG)的影响.发现Cl-对CNT/PMS体系氧化降解OG的过程具有双重影响,低浓度Cl-会抑制OG的脱色,高浓度Cl-会促进OG的脱色；无CNT存在时Cl-会直接与PMS作用使OG脱色.研究了CNT/PMS/Cl-体系降解OG的主要影响因素(PMS浓度、反应温度、OG初始浓度、Cl-浓度、初始pH)和反应机制,结果表明PMS浓度为1.6mmol/L、反应温度为25℃时、OG初始浓度为0.8mmol/L、Cl-浓度为50mmol/L和pH=7的条件下,25min内OG脱色率可达到100%,反应体系的活化能为88.45kJ/mol；随着初始pH升高, OG脱色率先减后升,降解OG的活性物质为SO4-?和 HOCl.对 OG 降解过程的矿化率分析表明,CNT 存在条件下 OG 的矿化率要比无 CNT 存在时要好；然后通过紫外可见扫描光谱扫描和GC-MS分析,发现OG分子中偶氮键及萘环结构被破坏后,生成了其他小分子物质.“,”The radical was formed by the carbon nanotube (CNT) activation of peroxymonosulfate (PMS). Effect of chloride ion (Cl-) on degradation of Orange G (OG) by CNT/PMS system were investigated. Cl-had a dual effect on OG decolorization in the CNT/PMS system. Low dosage of Cl-could inhibit OG decolorization, whereas high dosage could promote its decolorization. Meanwhile, Cl-could directly react with PMS alone to decolorize OG. In the CNT/PMS/Cl-system, effect of various factors were explored, including PMS dosage, reaction temperature, initial concentration of OG, Cl-concentration, and initial pH, and the degradation mechanism was further proposed. The results indicated that 100%decolorization of OG was observed after 25min when 1.6mmol/L of PMS, 0.08mmol/L of OG, 50mmol/L of Cl- were present at 25℃. The activation energy of reaction system was determined to be 88.45kJ/mol. With the increasing initial pH, OG decolorization was decreased first and then gradually increased. Both of SO4-? and HOCl were found to be responsible for OG degradation. The mineralization rate during the degradation of OG were analyzed, and higher mineralization rate was observed when CNT was present in the system. From the analysis of UV-vis spectra and GC-MS, the azo band and naphthaline ring of OG were destroyed to generate other small intermediates.