沥青基球状活性炭担载TiO_2制备光催化剂及其降解甲基橙的研究

Study on Preparation of TiO_2/PSAC Composite Photocatalyst and Degradation of Methyl orange

以微孔型沥青基球形活性炭(PSAC)为载体,钛酸四正丁酯为钛源,采用溶胶-凝胶法和浸渍-烧结法分别制备了TiO2/PSAC复合材料.通过XRD、SEM、EDS、TGA等分析技术对PSAC及TiO2/PSAC复合材料的结构进行了表征;以水溶性有机物甲基橙(MO)为探针,考察了两种方法制备的复合材料对于目标降解物的光催化降解性能以及循环反应性能.结果表明,两种方法制备所得样品均为微孔结构,且具备了光催化降解MO的活性.其中,溶胶-凝胶法所制备的TiO2/PSAC复合光催化剂在高纯氮气环境下于450℃煅烧后,TiO2晶型为锐钛矿型,并以薄膜形式涂覆在PSAC表层,在紫外光照射下对MO的光催化降解率可达96.7%,第三周期反应结束后降解率仍能保持在84.0%,分别高于浸渍-烧结法制备样品的90.1%和69.1%,而纯PSAC吸附对于MO的去除率为55.0%左右.

The TiO2/PSAC composites were prepared by sol-gel method and impregnation-calcination method,respectively,with tetrabuty tinanate as titanium source and pitch-based spherical activated carbon（PSAC） as carrier.The composite catalysts were characterized by XRD,SEM,EDS,TGA.The photocatalytic degradation activity and cyclic reaction of samples were studied using methyl orange as probe.The results indicated that the samples synthesized from the two methods exhibits microporous structure and shows high photocatalytic activity.The composite prepared by sol-gel method sintered at 450℃ in a N2 atmosphere has an anatase crystal model coating on the surface of carrier,and its photocatalytic activities for MO can reach 96.7% after cycle reaction,84.0% after third cycle,while the activities of composite sample prepared by impregnation-calcination method can just reach 90.1% and 69.1%,respectively,superior to pure PSAC just about 55.0%.