2.浙江泷赢环境科技有限公司,杭州 310012
1.College of Environment, Zhejiang University of Technology, Hangzhou 310032, China
2.Zhejiang Longying Environment Technology Co. Ltd., Hangzhou 310012, China
将Ce掺杂ZnO光催化剂通过负载活性炭 (AC)的方式制备Ce-ZnO/AC吸附-催化复合材料,并以对二甲苯为典型挥发性有机污染物(VOC),研究其在真空紫外体系中光催化转化性能。结果表明:活性炭的负载能有效提高臭氧的利用效率,强化对二甲苯的去除率和矿化率;当Ce-ZnO与活性炭的负载比例为1∶2时,复合材料的光催化性能达到最优,此时对二甲苯的转化率达到95%以上;活性炭的负载不仅可使污染物与催化剂充分接触,还可有效利用臭氧从而产生·OH等自由基,协同促进对二甲苯的降解,同时更多的中间产物被降解。复合催化材料显示了良好的稳定性,在利用5次后,仍可再生恢复其光催化性能至初始状态。相对于单独的真空紫外光解,Ce-ZnO/AC吸附-催化复合材料与真空紫外体系耦合降解二甲苯的能量利用率提高了2倍,经济性好。
An adsorption-catalytic composite catalyst Ce-ZnO/AC was prepared by loading of activated carbon (AC) on Ce-doped ZnO photocatalyst. The photocatalytic degradation experiments were carried out using p-xylene as a model volatile organic compound (VOC) in photocatalytic reactor, and the photocatalytic and conversion of p-xylene in vacuum ultraviolet irradiation environment was studied. The results showed that the loading of activated carbon could increase the ozone utilization efficiency, and enhance the removal rate and mineralization rate of p-xylene. The composite catalyst achieved the best effect when the ratio of Ce doped ZnO to activated carbon was 1∶2, and the conversion rate of p-xylene reached over 95%. The loading of activated carbon not only promoted the contact between pollutants and the catalyst, but also effectively utilized the ozone to generate free radicals such as ·OH, which could synergistically promote the degradation of p-xylene and more intermediates compared to the catalytic without active carbon. The composite catalyst also showed good stability and could be regenerated and recovered its initial adsorption-catalytic performance after five cycles. The energy efficiency of composite catalyst increased by double compared to VUV alone, and it had good economic effect.
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Schematic diagram of the photo-reactor system.
在暗反应过程中 Ce-ZnO∶AC=1∶2时对二甲苯的吸附
Adsorption of p-xylene by composite catalyst with Ce-doped ZnO∶AC = 1∶2 during dark reaction
concentration and p-xylene removal efficiency under different processes of VUV-PCO system
concentration and p-xylene removal efficiency under different ratios of Ce-doped ZnO to activated carbon
对二甲苯在不同工艺下光催化降解的气相中间产物
Gas phase intermediates of p-xylene photo photocatalytic degradation under different processes
Catalytic stability of the VUV-PCO
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