TiO2／Mg（OH）2复合材料对有机污水中甲基橙的光催化降解动力学的研究

采用溶胶一凝胶法制备了纳米TiO2，并以TiO2和镁盐溶液为前驱物用氨气鼓泡法制得了TiO2／Mg（OH）2复合材料．利用氢氧化镁在水溶液中较强的吸附能力和TiO2对有机物的催化降解作用，研究TiO2／Mg（OH）2复合材料对有机污水中的甲基橙暗反应吸附规律和光反应催化降解性能．结果表明：当Ti02／Mg（OH）2加入量为1g·L^-1。时，在可见光下照射180min后，对有机污水中含20mg·L^-1的甲基橙的降解率达到98．00％，同时在同等条件下选用国家标准（30mg·L^-1亚甲基蓝溶液）作为参照时，降解率可达99．20％．TiO2／Mg（OH）2复合材料对污水中甲基橙的催化降解反应较好地符合Langmuir动力学模型，可用一级反应动力学方程进行描述．

Kinetics of photocatalytic degradation of methyl orange in organic waste water by magnesium hydroxide/titanium dioxide composite material

In this paper, TiO2 nanometer powder was prepared by sol -gel method, and TiO2/Mg（OH）2 composite material was prepared by the ammonia bubbling method with nanometer titanium dioxide as the precursor. Mg（ OH）2 has a strong adsorption effect in a liquid, and TiO2 has a high degradation efficiency to organic matter in waste water, TiO2/Mg（OH） 2 composite material was used to deal with the organic waste water. The dark reaction adsorption and the photocatalytic degradation for the methyl orange were researched. The result showed that： when 1 g .L-~TiO2/Mg（OH）2 composite material was put in a methyl orange solution, and the solution was exposed 180 min under visible light, the degradation rate of methyl orange in solution reached 98% . The degradation regularity obeyed the Langmnir Dynamic Model, and the photocatalytic oxidation reaction of the methyl orange with TiO2/Mg（ OH）, composite materials can be described with the first order reaction kinetics eauation.