多级孔TiO_2/ZSM-5催化剂的孔道效应对亚甲基蓝催化降解性能影响

Effect of Pore Structure of Hierarchical TiO_2/ZSM-5 Catalyst on the Degradation Properties of Methylene Blue

以廉价凹凸棒石为原料,通过调控介孔模板剂聚乙二醇(PEG-1000)用量用水热合成法制得多级孔ZSM-5分子筛,并用溶胶-凝胶法制备了TiO_2/ZSM-5光催化剂。通过FT-IR、XRD、SEM和N2吸附-脱附对多级孔TiO_2/ZSM-5光催化剂的官能团、晶体结构、形貌和孔道特征进行表征,并对典型的亚甲基蓝印染废水进行光催化实验,考察模板剂用量和TiO_2负载量对光催化剂孔道效应和催化性能的影响。结果表明:ZSM-5分子筛作为载体,其介孔体积与介孔模板剂PEG用量成正比,调节PEG用量可定向控制载体的孔道结构;TiO_2负载量在一定程度上影响光催化效率和载体孔体积。当PEG为0.16 g,TiO_2负载量为10%时,多级孔TiO_2/ZSM-5具有良好光催化活性,光照40min光催化降解率可达90%。

The ZSM-5 hierarchical zeolite was successfully synthesized with cheap attapulgite by hydrothermal synthesis and regulating the dosage of Polyethylene glycol(PEG-1000)which was used as mesoporous template,and the TiO2/ZSM-5 catalyst was synthesized by sol-gel method.The functional groups,crystal structure,morphology and pore characteristics of hierarchical TiO2/ZSM-5 catalyst were characterized by FT-IR,XRD,SEM and N2 adsorption-desorption.Photocatalytic experiments using the typical methylene blue dyeing wastewater,to inspection the amount of templating agent and the loading of TiO2 how to affect the pore structure of TiO2/ZSM-5 catalyst.The results show that as mesoporous template,the amount of PEG is proportional to the mesoporous volume of carrier which can be adjusted to directionnally control the pore structure of the carrier,the TiO2 loading affects the photocatalytic efficiency and the carrier pore volume to some extent.When the PEG is 0.16 g and the TiO2 loading is10%,the hierarchical TiO2/ZSM-5 has good photocatalytic activity,and the photocatalytic degradation rate can reach 90%after 40 min illumination.