TiO2/EP光催化降解水体中微污染磺胺嘧啶的研究

制备了膨胀珍珠岩（EP）为载体的TiO2催化剂（TiO2/EP）,对使用较为广泛的抗生素磺胺嘧啶（SDZ）进行了光催化降解研究,探讨了TiO2的负载量、溶液的初始浓度、初始pH、无机离子（HCO3^-、SO4^2-和Cl^-）和腐殖酸（HA）对SDZ降解效果的影响。结果表明：SDZ的光催化降解符合一级反应动力学方程;当TiO2最佳负载量为20 wt%,SDZ浓度为5 mg/L,pH=6.7,紫外光照射强度为1 000μW/cm^2,反应时间为45 min时,SDZ的降解率达到96%;HCO3^-在低浓度时能促进SDZ的光催化降解,高浓度时促进作用不明显;SO4^2-和Cl^-对SDZ的光催化降解有轻微的抑制作用;HA对SDZ光催化降解有显著的抑制作用,浓度越高,抑制作用越强。UV-TiO2/EP是一种去除水体中微污染SDZ的有效方法。

Photocatalytic degradation of trace sulfadiazine in aqueous solution by TiO2 immobilized on expanded perlite

In this article,the degradation of trace sulfadiazine in water by TiO2/EP was investigated.The effects of quantity of TiO2 loading,concentration of sulfadiazine,pH value of solution,inorganic ions（HCO3^-,SO4^2- and Cl^-）and humic acid were investigated.The results showed that the degradation reaction follows the characteristic first-order reaction kinetics.The degradation efficiency of SDZ reached 96% under the conditions： the initial concentration of SDZ was 5 mg/L,the optimal quantity of TiO2 loading was 20 wt%,the pH was 6.7,light intensity was 1 000 μW/cm^2 and the reaction time was 45 min.The degradation efficiency of SDZ was enhanced at low concentration and was not remarkable at high concentration by HCO3^-,but it was inhibited by the SO4^2- and Cl-slightly,and the degradation efficiency of SDZ was inhibited by HA significantly,the inhibition was stronger as the concentration was higher.The experiment showed that UV-TiO2/EP is an effective method to remove trace sulfadiazine in water.