活性炭吸附-脉冲放电等离子体/催化降解水中典型全氟化合物的研究

Perfluorinated compounds (PFCs) are a family of persistent organic pollutants (POPs) existing in the environment, which are incredibly resistant to breakdown due to the stable molecular structure, causing various harms. The low concentration PFCs can be adsorbed by activated carbon (AC) effectively, but not be removed completely, which is easy to cause secondary pollution; non-thermal plasma can be obtained at ordinary temperatures and pressures, and generate chemical reactions which are hard to react in traditional chemical methods, also produce strong oxidized active substances to eliminate contaminants, becoming one of the effective ways to degrade organic pollutants. Because the active materials of pulsed discharge plasma are more and strong, to solve the pollution problem of low concentration PFCs in water, this project use granular activated carbon to concentrate PFCs, and then the adsorbed PFCs is degraded by the effects of pulsed discharge plasma and heterogeneous catalysis. Those catalytic processes are based on the reaction of discharge streamer catalysis and ozone catalysis, and could enhance the amount of active species, increase the removal of PFCs and energy efficiency of the discharge treatment. The essence of PFCs degradation and AC regeneration in discharge plasma / catalysis is illuminated by diagnosing the function relationship between active species and PFCs in discharge, building the plasma catalysis effect and analyzing the PFCs degradation pathway. This study could provide references for the low concentration and refractory POPs removal by discharge plasma technology.

全氟有机化合物（PFCs）是一类广泛存在于环境中的持久性有机污染物（POPs），因分子结构极稳定，在环境中缺乏天然降解途径而造成多方面危害。通过活性炭吸附是去除水中有机污染物的有效手段，但未对其彻底降解，易造成二次污染；而常温常压下产生的低温等离子体可发生传统化学方法难以实现的化学反应，生成强氧化性活性物质，是降解有机污染物的有效方法之一。本项目依据脉冲放电等离子体产生活性物质强且多的特点，针对水中低浓度PFCs污染问题，先用活性炭对其吸附，再用脉冲放电激发活性炭负载金属氧化物的多相催化效应，产生流光催化和臭氧催化等反应过程，增加活性物质数量，提高PFCs去除效果及放电能量利用效率。通过诊断放电过程中活性物质与PFCs的作用关系、实现等离子体催化效应以及解析PFCs降解途径，阐明放电等离子体/催化降解PFCs及再生活性炭的本质。本研究将为放电等离子体技术处理低浓度、难降解POPs提供参考。

全氟有机化合物（PFCs）是一类广泛存在于环境中的持久性有机污染物，因分子结构极稳定，在环境中缺乏天然降解途径而造成多方面危害。本项目以典型PFCs作为目标污染物，在活性炭吸附-气相沿面放电等离子体体系中，系统考察PFCs在不同放电电压、放电频率、通气速率、活性炭投加量等条件下的降解特性，明确了PFCs在协同系统中的最佳处理条件。以浸渍法在活性炭上负载铁锰双金属氧化物，将制备的负载型活性炭加入放电等离子体系统中，考察了不同电气条件放电电压、放电频率、空气流量、催化剂投加量等对PFCs的降解特性，获得了此协同体系降解典型PFCs的处理条件范围。应用自由基掩蔽实验确定了本体系的降解主要活性物质。应用液相-质谱联用考察了PFCs降解过程中主要的降解副产物的生消规律。结合活性炭样品的表征结果、PFCs降解与主要活性物质产生及利用的规律，综合分析并阐明了等离子体/负载型活性炭催化处理PFCs的机理。本项目共发表SCI研究论文12篇，申请发明专利2项，指导硕士研究生3名。