氟苯再生酸氧化过滤—冷却结晶—吸附—减压浓缩净化工艺

Purification of regenerated acid of fluorophenyl by oxidation,crystallization,adsorption and vacuum concentration processes

为了开发一种氟苯再生酸的资源化利用途径,对某生产氟苯及其系列产品的化工厂排出的废酸进行了研究,提出了氧化过滤—冷却结晶—吸附—减压浓缩的净化工艺,并且在吸附阶段,通过自制改性的活性炭作为吸附剂来对氧化、结晶的酸液进行吸附,COD去除率高达96.8%。同时确定了氧化过滤阶段的最佳工艺条件:废酸/氧化剂为4∶1,温度为110℃,反应时间为120 min,吸附阶段的最佳工艺条件:吸附剂的投加比为10 g·L^(-1),吸附时间为12 h,吸附温度为30℃。结果表明,COD去除率高达99.4%,净化后废酸的硫酸含量达到82.4%。

In order to develop a resourceful way of utilizing regenerated fluorophenyl acid,purification processes based on waste acid produced in fluorobenzene factories were developed. These processes included oxidation,crystallization,adsorption,and vacuum concentration. Homemade modified activated carbon was used in the adsorption stage,and the optimum technical conditions for oxidation were a 4 ∶ 1 ratio of waste acid to oxidant,110 ℃,and 120 min reaction time. The optimum conditions for adsorption were 10 g·L^-1of adsorbent,a 12 h adsorption period,and an adsorption temperature of 30 ℃. The results indicated that the removal rate of COD was up to 99. 4%,and that the content of sulfate reached 82. 4% after purification.