负载型TiO_2复合材料对甲基橙的吸附行为及光催化降解动力学

以4A沸石和天然蛭石为载体,钛酸四丁酯为钛源,采用溶胶-凝胶法制备了TiO2/4A沸石和TiO2/天然蛭石光催化复合材料,研究了复合材料对偶氮染料甲基橙的暗态吸附规律和光降解性能。结果表明:复合材料对甲基橙的吸附规律都较好地符合Langmu ir和Freund lich吸附等温模型;在紫外光辐照30 m in条件下,TiO2/4A沸石和TiO2/天然蛭石光催化材料对6.11×10-5mol/L的甲基橙水溶液的脱色率分别达到78.5%和84.6%,比同种方法制备的纯TiO2(68%)高,而且对甲基橙光催化反应可用一级反应动力学方程进行描述。

Adsorption Behavior and Photocatalytic Discoloration Kinetics of Methyl Orange on Supported TiO2 Composite

TiO_2/zeolite 4A and TiO_2/vermiculite composites were prepared by sol-gel technique with tetrabutyl titanate as the titanium source,and zeolite 4A and natural layered vermiculite as the supports.The adsorption and photocatalytic oxidation proceses of methyl orange on the composites were studied.The results indicate that the adsorption law of methyl orange on the composites fit in well with the Langmuir model and Freundlich model.With 6.11×10~(-5) mol/L of methyl orange solution concentration and 2 g/L of catalyst concentration under UV light irradiation for 30 min,the discoloration rate of methyl orange solution reached 84.6% on TiO_2/vermiculite and 78.5% on TiO_2/zeolite 4A,higher than that on bare TiO_2 prepared by sol-gel technique under same experimental conditions.The kinetics of photocatalytic oxidation fits in with the first-order kinetic model.