构建具有高能晶面暴露的催化材料低温催化氧化氯苯工业废气的研究

Based on the urgent demand in air pollution control of China, this project focuses on the development of efficient catalytic oxidation technology for chlorinated volatile organic compounds (CVOCs, particularly containing chlorobenzene) treatments, aiming to obtain advanced catalysts and effective fabrication methods to drive this technology into industrial application. In virtue of the excellent catalytic performance of high energy crystal surface (HECS), a low-temperature catalytic oxidation of chlorobenzene process was subsequently developed, which explores the coupling mechanism between the Cl- and HECS and evaluates how this coupling affects the thermal stability of the HECS catalysts in catalytic oxidation CVOCs. By means of high resolution transmission electron microscopy (HR-TEM), infrared (FTIR), temperature programmed reduction (TPR), et al., the project then investigates the active centers and catalytic oxidation mechanism of the HECS catalysts, which is expected to lead to the adjustments of proper explored HECS for the catalysts. Meanwhile, this project also puts forward a new fabrication route (using supercritical water as reaction medium) for the syntheses of HECS catalysts, aiming to effectively overcome the bottleneck of these catalysts in industrial-scale production. Eventually, we conduct an industrial fabrication process to coat the resulted powder HECS catalysts onto monolithic honeycomb, attempting to yield the sustainable monolithic honeycomb supported HECS catalysts that are with high mechanical strength, remarkable low temperature activity and good thermal stability and to provide theoretical and practical guidance for the developments of catalytic oxidaiton technologies in CVOCs efficient removal.

本课题基于我国目前在大气污染治理方面的迫切需求，研究开发高毒性含氯挥发性有机物（CVOCs），特别是氯苯类CVOCs的催化治理技术，重点研究可支撑该技术工业应用的核心催化剂配方及整体式催化剂成型工艺；借助高能晶面优异的催化特性，首次尝试将其应用于氯苯的低温催化降解，探索在催化反应过程中Cl-与高能晶面的耦合以及该耦合对高能晶面稳定性的影响；通过HR-TEM、红外、程序升温等表征手段，明确催化剂的活性中心和催化机理，进而优化催化剂晶面的选择性暴露。课题还利用超临界水的特殊环境，构建了高能晶面催化剂的全新制备路径，期望通过该路径的成功构建能解决催化剂工业化扩大生产的问题。最后，基于粉体催化剂的核心配方，课题研究了整体式蜂窝状催化剂的工业成型工艺及关键参数，期望能获得具有较高机械强度、良好低温活性和稳定性、适合工业应用的整体式工业催化剂，为我国CVOCs的高效净化脱除进行理论指导实践的尝试。

当前我国环保形势严峻，废气污染问题尤为突出。挥发性有机物（VOCs），特别是高毒性的含氯挥发性有机物（chlorinated VOCs）的环境风险愈来愈大，其治理需求日趋迫切。催化燃烧法作为一种高效、经济、可行的消除有机氯污染物的方法面临着催化剂易中毒、运行温度高、易导致次生污染等问题。本项目针对含氯VOCs催化氧化过程进行了深入探索，系统研究了氧化物基催化剂在催化氧化含氯VOCs过程中催化剂表面的氯吸脱附行为以及构效关系，特别对反应的副产物种类以及生成路径进行了分析，剖析了反应过程的二次污染并提出了控制策略；另外，为实现粉体催化剂的工业成型，开发了一种涂覆成型的粘结剂配方，显示出良好的工业应用前景。截至目前，本项目研究共发表SCI论文8篇，其中影响因子大于5的论文7篇，包括Appl. Cat. B-Eviron. 1篇，Environ. Sci. Tech. 3篇等，申请国家发明专利1项，培养博士研究生3名（毕业2名），硕士研究生2名，完成了项目的考核目标。