膨润土负载锌-钴催化臭氧处理模拟染料废水

Bentonite supported Zn-Co ozone catalyst for treatment of simulated dye wastewater

为获得高效的臭氧催化剂,以膨润土作为载体,选择Fe^(3+)、Cu^(2+)、Mn^(2+)、Ni^(2+)、Co^(2+)、Zn^(2+)为活性组分,通过溶液混合法制备负载型催化剂,并以酸性大红模拟印染废水探讨负载型催化剂在催化氧化体系中对酸性大红的降解速率及动力学特点,最终筛选得到最优活性组分;根据正交试验设计获得催化剂最佳制备条件,并通过X射线衍射仪和扫描电子显微镜对其进行表征。试验结果表明:最佳双组分催化剂为膨润土负载Zn-Co催化剂;膨润土负载Zn-Co半峰宽小,晶型好;双组分催化剂最佳制备条件为:煅烧温度400℃,煅烧时间3 h,组分浓度1.2 mol/L,锌钴的量比1∶1,淀粉质量1.5 g(对应60 g膨润土)。用在此条件下制得的催化剂处理模拟染料废水时,通入臭氧反应10 min,即可去除99.92%的酸性大红;且催化剂重复利用4次后,其去除率仍达81.44%。

In order to obtain an efficient ozone catalyst, bentonite was used as carrier, and Fe3+, Cu2+, Mn2+, Ni2+, Co2+ and Zn2+ were selected as active components to prepare supported catalysts by a solution mixing method. The influence of supported catalysts on degradation rate and kinetic characteristics of acid red in catalytic oxidation system were studied, and then the best active components were obtained. According to orthogonal experimental design, the best catalyst preparation conditions were achieved, and characterized by X-ray diffraction and scanning electron microscopy. The results show that the best two-component catalyst is bentonite supported Zn-Co. The optimum conditions for the preparation of the two-component catalyst are as followed: the calcination temperature is 400 ℃, calcination time is 3 h, component concentration is 1.2 mol/L, mole ratio of Zn and Co is 1∶1 and starch content is 1.5 g(in terms of 60 g bentonite). The catalyst prepared under the conditions catalyzes the oxidation of acid red with ozone, and the removal rate reaches 99.92% after 10 min of ozone reaction. After the catalyst is reused for 4 times, the removal rate still reaches 81.44%.