脉冲气液两相放电等离子体耦合Fe改性的TiO2催化剂降解废水中的4-氯酚

为了提高酚类废水的降解效果，本文以4-氯酚为处理对象建立了多针-板式高压脉冲气液两相放电等离子体催化体系。实验制备了系列催化剂并进行了表征分析，考察了各因素对4-氯酚降解的影响，并分析了降解过程总有机碳（TOC）、中间产物及其浓度变化。结果表明，催化剂焙烧温度及投加量对降解率有很大影响；4-氯酚浓度为150mg/L时，在电极间距10mm、脉冲电压26kV、脉冲频率70Hz、曝气量4L/min条件下，添加0.05g焙烧温度为500℃的Fe-TiO₂催化剂与放电等离子体耦合降解效果最好。中间产物对苯酚、对苯醌、4-氯邻苯二酚在放电过程中浓度随着放电时间的延长先增大后减小，最后都趋于零。催化剂表征显示脉冲放电可以改变催化剂的晶形和结构，且掺杂Fe改性的Fe-TiO₂催化性能较好，能进一步提升4-氯酚的降解率。

4-Chlorophenol containing wastewater joint treated by pulsed discharge plasma in gas-liquid two phase and Fe-modified TiO2 catalyst

In order to improve the degradation of phenols in wastewater, a multi-needle plate catalysis system with high voltage pulsed gas-liquid two-phase discharge plasma was established for the removal of 4-chlorophenol. A series of catalysts were prepared and characterized, and the effects of various factors on 4-chlorophenol degradation were investigated by analysis of TOC, intermediate products and their concentrations in the degradation process. The results showed that catalyst roasting temperature and dosage had a great influence on the degradation rate of 4-chlorophenol. When the concentration of 4-chlorophenol was 150mg/L, under the conditions of electrode spacing 10mm, pulse voltage 26kV, pulse frequency 70Hz, aeration 4L/min, the discharge plasma with the Fe-TiO₂ catalyst of 0.05g calcinated at 500℃ gave the best degradation effect. The concentrations of byproducts such as p-phenol, p-benzoquinone and 4-chlorocatechol increased firstly and then decreased gradually and eventually disappeared with the increase of discharge time. Characterization results showed that the pulse discharge changed the crystal form and structure of the catalyst, and the Fe-TiO₂ modified with Fe had good catalytic performance, which further improved the degradation rate of 4-chlorophenol.