Fe3O4@CuO/石墨烯磁性纳米复合材料及其非自由基活化过硫酸盐高效降解氯代芳烃研究

Chlorinated aromatic hydrocarbons are high toxicity and low biodegradability in wastewater. Persulfate activation system has strong oxidation ability and effects on the degradation of refractory pollutants. Inorganic function materials possesses remarkable advantages for activating persulfate in processing chlorinated aromatic hydrocarbons. It has attracted extensive critical attention to improve the degradation efficiency and is an important research subject in the field of material and environment pollutant control. In this project, a new non-radical composite functional material will be prepared for the activation of persulfate with no radical for degradation of chlorinated aromatic hydrocarbons selectively in water. Selective non-radical catalysis will composite with separable supporters and high adsorption materials. A cost-benefit approach to eliminate chlorinated aromatic hydrocarbons efficiently without secondary pollution will be obtained. The catalyst can be easily separated and good reusability. (1) Chloroaniline will be used as target pollutant. Fe3O4@CuO/graphene composite will be designed and prepared to meet the demand of constructing a novel system of non-radical persulfate activation. The operation mechanism of the activated persulfate will be studied. The formation of high chlorinated intermediate products and low polymers will be inhibited during the degradation of chloroaniline by non-radical activating persulfate. Chloroaniline oxidation efficiency will be improved. (2) Research persulfate activation mechanism in chloroaniline degradation by Fe3O4@CuO/graphene composite, illuminate the effect of composite micro-structure on activation and degradation. (3) Study chloroaniline degradation progress in Fe3O4@CuO/graphene-persulfate system to verify the critical factors of intermediate products and low polymers formation. Finally, get applicable persulfate non radical activation functional materials, providing a theoretical and technical basis to improve the degradation efficiency of chlorinated aromatic hydrocarbons pollutants.

污水中的氯代芳烃污染物毒性大、生物降解难，通过无机功能材料活化过硫酸盐降解氯代芳烃具明显优势，是材料和污染控制领域的重要研究课题。本项目拟设计合成具有非自由基活化功能的复合材料，非自由基催化物质与可分离磁性材料和高吸附材料复合，实现氯代芳烃的低成本高效降解、无二次污染以及活化材料的回收循环利用。（1）以氯苯胺为目标污染物，通过设计、合成Fe3O4@CuO/石墨烯复合材料非自由基活化过硫酸盐，抑制含氯中间产物及低聚物的形成，实现氯苯胺高效降解。（2）明确Fe3O4@CuO/石墨烯复合材料微结构和组分与活化过硫酸盐分解氯苯胺效率的关系，阐明其非自由基活化降解氯苯胺的作用机制。（3）研究氯苯胺的降解历程，探明影响含氯中间产物与低聚物形成的关键因素与条件，确立提高氯苯胺降解率的原理和方法。本研究将获得高催化活性、可回收利用的复合功能材料，为其非自由基活化过硫酸盐高效降解氯代芳烃提供理论基础和技术。

难降解有机污染物的去除是水污染控制的热点和难题。氯代芳烃（如多氯联苯、氯苯胺、氯酚等）是废水中重要有机污染物，毒性大，生物降解难，过硫酸盐活化技术氧化降解氯代芳烃具明显优势，是材料和污染控制领域的重要研究课题。但是氯代芳烃在过硫酸盐活化体系存在着产生分子量大、更难以降解的含氯中间产物和低聚物现象，导致降解效率低下。亟待寻找降解氯代芳烃污染物的有效方法。. 本项目通过设计合成具有非自由基活化功能的复合材料Fe3O4@CuO/石墨烯复合材，明确了非自由基活化过硫酸盐的作用机制；构建过硫酸盐非自由基活化体系，抑制含氯中间产物和低聚物的形成，提高过硫酸盐的氧化效率，实现氯苯胺的高效降解。. 研究结果表明，CuO及其复合材料对过硫酸盐的活化是非自由基过程为主，体系中活性氧化性物质是在CuO表面被活化的活性过硫酸盐分子，体系溶液中含有少量的硫酸自由基或羟基自由基，水中共存的氯离子和碳酸氢根离子对目标污染物的降解影响很小，最佳降解pH为中性。CuO/石墨烯复合材料提高了CuO对过硫酸盐的活化能力，电子通过CuO和石墨烯间形成的C-O-Cu键从rGO中的π键转移到CuO表面形成富电子中心，强化了过硫酸盐的非自由基活化。不同形貌CuO对过硫酸盐活化效率具有较大影响，对过硫酸盐的活化效率从大到小排列为片状、纺锤状、球状，片状CuO主要暴露晶面为（0 0 1），纺锤状和球状的（0 0 1）晶面比例较少，过硫酸盐活化对（0 0 1）晶面的具有依赖性。非自由基活化过硫酸盐体系展现了对多种氯化有机物的选择性去除能力。在CuO/rGO-PS非自由基体系，对氯苯胺在体系中最容易被降解，然后是三氯酚、二氯酚和氯酚，带苯环的TCP比含碳碳双键的TCE更容易被降解。. 本项目获得高催化活性的复合功能材料，为系统研究非自由基活化过硫酸盐的作用机制、揭示影响含氯中间产物与低聚物形成的关键因素与条件、获得具有非自由基活化过硫酸盐性能及可回收利用的功能材料奠定科学基础，对污染治理、保护环境具有重要意义。