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活化过硫酸盐产生硫酸根自由基的高级氧化技术在水环境污染物治理中引起了广泛的关注和研究.本研究采用水热法制备磁性氮掺石墨烯(M-N-G)作为催化剂.利用SEM、BET、XRD和VSM等手段表征材料,系统研究了该材料活化过硫酸盐降解亚甲基蓝的效能.结果表明:M-N-G的比表面积为94.35 m2·g-1,磁性Fe3O4分布在材料表面,能有效的活化过硫酸钾降解亚甲基蓝.当催化剂的用量为200 mg·L~(-1),过硫酸钾浓度为0.4~0.5 mmol·L~(-1)时,在p H=3~6时对10 mg·L~(-1)亚甲基蓝的降解率达90%以上.体系温度在15~32℃时,降解速率常数在0.0227~0.0488 min-1,反应活化能为33.7 k J·mol-1.EPR分析及自由基漼灭实验证明了体系中有羟基自由基和硫酸根自由基产生.TOC分析结果表明:TOC去除率可达50%.M-N-G经过简单的稀硫酸和水洗后,可高效重复利用4次.该技术方法简单、高效、无二次污染,能为有机污染物废水处理提供一种新的方法选择.
Activated persulfate sulfate radical generating advanced oxidation technology in the water environment pollutants caused widespread concern and research.In this study, hydrothermal method for the preparation of magnetic nitrogen-doped graphene (MNG) as a catalyst.Using SEM, BET , XRD and VSM were used to characterize the material. The effect of the material on the degradation of methylene blue by persulfate was systematically studied. The results showed that the specific surface area of MNG was 94.35 m2 · g-1. Magnetic Fe3O4 was distributed on the surface of the material, When potassium sulfate was used to degrade methylene blue, when the amount of catalyst was 200 mg · L -1 and the concentration of potassium persulfate was 0.4 ~ 0.5 mmol·L -1, 10 mg · L -1 The degradation rate of L-methylene blue was over 90% .The degradation rate constant was 0.0227 ~ 0.0488 min-1 and the reaction activation energy was 33.7 kJ · mol-1 at 15 ~ 32 ℃ Free radical scavenging experiments showed that the system has hydroxyl radicals and sulfate radical generation.TOC analysis results show that: TOC removal rate of up to 50% .MNG after a simple dilute sulfuric acid and water can be efficiently reused 4 times. The technical method is simple, efficient, no secondary pollution, organic wastewater treatment can be raised A new method of selection.