甲基对硫磷磁性印迹复合光催化剂的制备及其光催化性能研究

Synthesis and photocatalytic property of TiO2-MPIPs

以自制的Fe3O4@SiO2@TiO2为载体,甲基对硫磷(MP)为模板分子,甲基丙烯酸(MAA)和4-乙烯基吡啶(4-VP)为功能单体,乙二醇二甲基丙烯酸酯(EGDMA)为交联剂,采用表面分子印迹法制备了磁性分子印迹复合光催化剂TiO2-MPIPs,并对其进行表征和光催化特性研究。结果表明:当n(MP)∶n(MAA+4-VP)∶n(EGDMA)为1∶8∶18,乙烯基改性Fe3O4@SiO2@TiO2用量为33mg时,光催化性能达到最佳。TiO2-MPIPs对模板分子MP具有良好的特异性识别和光催化降解作用,45min内快速达到吸附平衡,最大吸附容量为44.5mg/g,紫外光照射70min,对MP的降解率达到96.8%;与乐果相比,TiO2-MPIPs对MP的光催化降解选择性系数为2.73,是磁性非分子印迹复合光催化剂TiO2-NIPs或未改性Fe3O4@SiO2@TiO2选择性系数的3.10倍、2.55倍。

By using Fe3 O4@SiO2@TiO2 as the carrier,methyl parathion(MP)as the template molecule,methacrylic acid(MAA)and 4-vinylpyridine(4-VP)as the functional monomer,and ethyleneglycol dimethacrylate(EGDMA)as the crosslinking agent,the magnetic molecularly imprinted composite photocatalyst(TiO2-MPIPs)was prepared by surface polymerization method,and studied its characterization and photocatalytic properties.The results shown that when the ratio of n(MP)∶n(MAA+4-VP)∶n(EGDMA)was 1∶8∶18,and the amount of Fe3 O4@SiO2@TiO2 modified by ethylene was 33 mg,the photocatalytic performance was the best.TiO2-MPIPs had good specific recognition and photocatalytic degradation of the template molecule MP and quickly reached the adsorption equilibrium within 45 minutes with the maximum adsorption capacity at 44.5 mg/g and the degradation rate of MP at 96.8%after70 minutes\UV irradiation.TiO2-MPIPs selectivity coefficient of photocatalytic degradation for MP was 2.73 as compared to that with dimethoate,3.10 times and 2.55 times that of the magnetic non molecularly imprinted composite photocatalyst(TiO2-NIPs)and the carrier(Fe3 O4@SiO2@TiO2)respectively.