Fe/Mn-SAC催化粒子电极三维电Fenton降解硫化矿浮选废水中巯基捕收剂的机理研究

The typical mercapto collectors (butyl xanthate and aniline aerofloat) residual in nonferrous metal sulfide mineral floatation wastewater exert severe deterioration on ecological environment of mine district due to the high toxicity and poor degradability. To solve the environmental problems caused by mercapto collectors, three-dimensional electro-Fenton system based on electro-Fenton coupled with three-dimensional electrodes is proposed in this project to degrade the mercapto collectors, which exerts both advantages of electro-Fenton and three-dimensional electrodes. The project will be conducted with the floating wastewater for sulfide lead-zinc ores in Hunan Huangshaping as the object to be treated. Firstly, a binary Fe/Mn-SAC (Fe/Mn loaded sludge deserved activated carbon) catalytic particle electrode will be synthesized from the raw materials of sewage sludge, waste iron sludge and electrolytic manganese slag via one-step method, combining the carbonization and Fe/Mn-loading process. Three-dimensional electro-Fenton system will be set up by employing the synthesized Fe/Mn-SAC as catalytic particle electrodes to degrade mercapto collectors. Secondly, to achieve the optimized control for degradation process of mercapto collectors by three-dimensional electro-Fenton, the influence mechanism of mercapto collectors removals by three-dimensional electro-Fenton will be illuminated based on statistical analysis methods and the main electrochemical and chemical reactions. Thirdly, the characteristics of the synthesized Fe/Mn-SAC catalytic particle electrode will be measured and analyzed with BET, FTIR, XPS et. al. A quantitative relationship model will be established between the characteristics of Fe/Mn-SAC catalytic particle electrode and degradation/catalytic processes of mercapto collectors within the three-dimensional electro-Fenton system by Back Propagation neural network. Finally, the degradation and catalytic mechanism of mercapto collectors by three-dimensional electro-Fenton with Fe/Mn-SAC catalytic particle electrodes will be revealed from the aspect of Fe/Mn-SAC characteristics, catalytic processes and thiol degradation, based on the developed quantitative relationship model, thiol degradation pathway as well as reaction kinetics, H2O2 generation kinetics model, radical scavenging tests and the variations of chemical binding state and functional groups on Fe/Mn-SAC surface. This project intends to provide technical support and theoretical guide for efficient treatment and recycling of nonferrous metal sulfide mineral floatation wastewater, with academic and practical significances.

针对有色金属硫化矿浮选废水中典型的有毒、难降解巯基类捕收剂（丁基黄药、苯胺黑药）对矿山生态环境的严重破坏，本项目以湖南省黄沙坪铅锌硫化矿浮选废水为处理对象，采用剩余污泥、铁泥和电解锰废渣等原材料，制备双组分Fe/Mn-SAC催化粒子电极，构建高效降解巯基捕收剂的三维电Fenton体系；运用统计学分析方法，结合（电）化学反应，解析其影响机制；利用BET、FTIR、XPS等检测技术，表征Fe/Mn-SAC特性；采用BP神经网络，构建Fe/Mn-SAC特性与巯基捕收剂三维电Fenton降解催化反应过程的量化关系模型，结合反应动力学、H2O2生成动力学模型、自由基捕获技术、双组分催化物种化学结合态变化、巯基降解路径，从催化粒子电极特性、催化反应过程、巯基降解等角度揭示巯基捕收剂Fe/Mn-SAC催化粒子电极三维电Fenton降解催化反应机理，为有色金属硫化矿浮选废水的高效处理提供理论和技术支撑。

针对有色金属硫化矿浮选废水中残留的难降解巯基捕收剂（苯胺黑药、丁基黄药）对矿山生态环境的严重破坏，本项目围绕Fe/Mn双组分催化粒子电极三维电Fenton降解巯基捕收剂的机理开展研究，通过制备Fe/Mn双组分催化粒子电极，构建三维电Fenton降解浮选废水中残留的巯基捕收剂，考察巯基捕收剂降解效能，解析降解催化反应机理。采用循环热解法分别制备了Fe/Mn-GAC和Fe/Mn-SAC双组分催化粒子电极（催化剂），运用响应面法对主要制备条件参数进行分析和优化，优化得到最优制备工艺参数为铁锰比9.50、制备温度362.07℃、总离子浓度1.09 mol/L。对制备的Fe/Mn双组分催化粒子电极（催化剂）的相关特性进行了表征分析，适量的Mn掺入增加了Fe3-xMnxO4的丰度，Mn(III)和Mn(IV)为主要存在形态；制备的Fe/Mn双组分催化粒子电极（催化剂）具有良好的空隙发育和较高的比表面积、铁锰双金属氧化物掺杂负载，这些特性为其作为高效稳定的催化粒子电极提供了有利条件。Fe/Mn双组分催化粒子电极（催化剂）在Fenton和三维电Fenton体系中均表现出较高的（电）催化活性，对苯胺黑药、丁基黄药的降解率和矿化率均较高，丁基黄药较苯胺黑药易降解，但进一步矿化较难。特殊的铁锰双金属氧化物掺杂显著提升了（电）催化活性，Mn通过直接和间接方式参与催化反应过程，增加催化活性位点和自由基产量，H2O2的催化分解和自由基的生成涉及Fe/Mn双组分催化粒子电极中的多种催化活性物种和多个催化活性位点，Mn的掺杂促进了电子传递并直接参与催化过程，进而提升催化活性和H2O2有效分解利用率。项目研究可应用于硫化矿浮选废水的高效处理及各种有机污染废水的处理，对于促进选矿废水高效处理和电化学水处理技术应用发展具有显著作用，为有色金属硫化矿浮选废水的高效处理提供理论和技术支撑。