TiO2-Al2O3复合粉体的制备及光催化性能

Al₂O₃陶瓷膜在过滤染料废水过程中容易被染料大分子堵塞,导致Al₂O₃陶瓷膜水通量下降。以钛酸丁酯、异丙醇铝为前驱体,采用溶胶-凝胶法制备Ti(OH)₄-AlOOH复合溶胶,经450 ℃烧成获得TiO₂-Al₂O₃复合粉体。以SEM、纳米粒度/电位仪作为主要表征手段,研究了不同Ti(OH)₄和AlOOH摩尔比对复合溶胶粒径分布的影响,进而探究TiO₂-Al₂O₃复合粉体的光催化性能。结果表明,Ti(OH)₄和AlOOH摩尔比为0~0.4时,随着Ti(OH)₄和AlOOH摩尔比的增大,胶粒的平均粒径从67.5 nm减小到34.0 nm,Ti(OH)₄-AlOOH复合溶胶的电位从43 mV升高至53 mV。当Ti(OH)₄和AlOOH摩尔比为0.4时,复合粉体对结晶紫的去除率高达79.3%,反应速率常数增大到了0.018 min^-1。TiO₂-Al₂O₃复合粉体制备的陶瓷膜能有效降解表面沉积的大分子,解决了陶瓷膜堵塞的问题。

Preparation and Photocatalytic Performance of TiO2-Al2O3 Composite Powder

The Al₂O₃ ceramic filter membrane is easily clogging by dye macromolecules during the process of filtering dye wastewater, resulting in a decrease in the water flux of the Al₂O₃ ceramic filter membrane. Ti(OH)₄-AlOOH composite sol was prepared by the sol-gel method with butyl titanate and aluminum isopropoxide as precursors, and TiO₂-Al₂O₃ composite powder was obtained by heating at a temperature of 450 ℃. The influence of the molar ratio of Ti(OH)₄ and AlOOH on the particle size distribution of composite sols and the photocatalytic performance of TiO₂-Al₂O₃ composite powders was characterized by using SEM, nanoparticle size/potential meter. The results show that when the molar ratio of Ti(OH)₄ and AlOOH is between 0 and 0.4, the average particle size of the colloidal particles decreases from 67.5 nm to 34.0 nm with the increase of the molar ratio of Ti(OH)₄ and AlOOH, and the Zeta potential of the Ti(OH)₄-AlOOH composite sol increases from 43 mV to 53 mV. When the molar ratio of Ti(OH)₄ and AlOOH is 0.4, the removal rate of crystal violet by composite powder up to 79.3%, and the reaction rate constant increases to 0.018 min^-1. The ceramic membrane prepared by TiO₂-Al₂O₃composite powder can effectively degrade the macromolecules deposited on the surface, and solve the problem of clogging of the ceramic membrane.