纳米二氧化钛粉体光催化染料脱色的研究

Research on Nano-TiO_2 Powder in Photocatalysising Decoloration of Dye

以钛酸四丁酯为原料,采用溶胶-凝胶法制备了纳米二氧化钛粉体.经XRD对制得的粉体进行了表征.以溶胶-凝胶法制得的二氧化钛粉体,利用紫外光催化反应装置,考察了溶液初始浓度变化、催化剂投加量以及pH值、光催化时间对甲基红降解率的影响.结果表明:随着溶液初始浓度增加,甲基红的降解率降低;染料在强酸性环境中的降解好于碱性环境,酸性环境中更容易进行光催化降解反应,去除率以及反应速率都大于碱性条件下的值.其中,当pH=3.0时,甲基红溶液在固定时间内的去除率最大;TiO2粉末投加量为0.7 g/L时,其具有良好的光催化脱色性能,经7 h光照,甲基红染料废水脱色效果好.

Nanosized titanium dioxide powder is prepared by sol-gel methods from tetrabutyl titanate. Prepared powder is charaterized by XRD technique. The decoloration of the dye is studied in Nano-TiO2 Powder which is prepared by sol-gel methods, decoloration rate of methyl red is studied by using ultra-violet lamp. The experiment led up to the fact that：as the increase of initial concentration , the degradation ratio of the methyl red is decreased; degradation ratio of the methyl red in the acidic environment is better than in the alkali environment , both removal ratio and reaction rate are greater than those in the alkali environment, when pH is 3.0, removal ratio of methyl red is maximum in the fixed time; at the recruitment of TiO2 is 0.7 g/L , decoloration rate is good. After seven hours illuminating, decolouration rate of the methyl red is good.