TiO2/HZSM-5 Was synthesized by a sol-gel method using the supporter of HZSM-5 modified by dif- ferent concentration of phosphoric acid. The photocatalysts were characterized by XRD, SEM, BET, FT-IR and XPS measurements. The results showed that phosphoric acid modification did not change crystalline struc- ture of ZSM-g zeolite and had minor effect on the surface morphology. TiO2 was coated on the surface of the ze-olite as TiO2 where titanium existed in its Ti4＋ oxidation state. There was no direct chemical bonding between TiO2 and the zeolite. Surfaee area of the supported photocatalyst increased drastically with increasing phosphor- ic acid concentration. Degradation rate of reactive brilliant red X-3B varied with phosphoric acid concentration,leading to the optimal concentration of 0.5mol/L. 50% TiO2/0.5HZSM-5 showed much higher photocatalytic activity than TiO2, resulting in 93.4% degradation of the dye after 2 h of irradiation, compared with 61.0%degradation on TiO2.%以不同浓度磷酸改性的HZSM-5为载体,采用溶胶-凝胶法制备得到TiO2/HZSM-5光催化剂,通过XRD、SEM、BET、FT-IR和XPS进行表征。结果表明,磷酸处理没有改变分子筛的晶体结构,对分子筛的表面形貌改变不大,负载后的TiO2包覆在分子筛表面。负载前后的TiO2表现为锐钛矿晶型,钛以四价钛的形式存在,氧化物的组成为TiO2。TiO2与HZSM-5没有发生化学键合作用,负载型光催化剂的比表面积随着磷酸浓度的增加而显著提高。活性艳红X-3B的降解率随磷酸浓度的增加而变化,最佳磷酸处理浓度为0.5mol/L。50%TiO2/0.5HZSM-5较TiO2有更高的光催化活性,紫外光照射2h可使活性艳红X-3B降解93.4%,而染料在TiO2上的降解率只有61.0%。
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