催化精馏法处理甲醛废水

通过催化精馏方法使废水中甲醛与加入的甲醇反应生成甲缩醛(DMM),同时实现废水中甲醛含量达标及其资源化利用。考察了醇醛摩尔比、反应温度、反应时间、催化剂添加量、塔顶回流比和待处理废水中甲醛质量分数6个因素对废水中甲醛去除率及产品甲缩醛质量分数的影响,结果表明,待处理废水中甲醛质量分数越高,加入的甲醇利用率越高,并总结出甲醛质量分数5%的废水最佳反应条件:反应温度80℃,醇醛摩尔比5,反应时间30 m in,催化剂加入量是待处理废水质量的1%,塔顶回流比3。在最佳条件下塔釜甲醛去除率达90%,塔顶甲缩醛质量分数达40%,废水中甲醛资源化利用率达98%以上。

Research on the Disposal Process of Formaldehyde Wastewater by Catalytic Distillation

In this paper,dimethoxymethane(DMM) was produced by the catalytic distillation in which formaldehyde was the pollutant in waste water and methanol was added.This process reduced the formaldehyde content in waste water within the emission regulation and realized the effective resource utilization according to the pollution(environmental) regulation.Contrast experiments are carried out for evaluating the six effects of the mole ratio of methanol and formaldehyde,reaction temperature,reaction time,the amount of catalyst,top reflux ratio and the formaldehyde content in wastewater on the formaldehyde disposal ratio and the content of DMM.The results have shown that methanol utilization efficiency will be higher as the content of formaldehyde in wastewater increases.Besides,the mole ratio of methanol and formaldehyde about 5,reaction temperature at 80 ℃,reaction time 30 min,the amount of catalyst 1% of the wastewater and the top reflux ratio 3 are the optimal disposal conditions according to the wastewater with 5% formaldehyde.Under those conditions,kettle formaldehyde disposal ratio can reach 90%,top DMM mass fraction 40%,and the formaldehyde utilization efficiency of wastewater above 98%.