从对羟基苯甲腈废水中回收苯酚和对羟基苯甲腈产品的技术研究

Study on the Technology of Recovering Phenol and p-Hydroxy Benzonitrile from p-Hydroxybenzonitrile Wastewater

利用对羟基苯甲酸经酰胺化脱水生产对羟基苯甲腈的工业生产过程中,会产生大量含酚的有机废水,对其进行一系列预处理:沉降、萃取、酸化、精馏、蒸馏等,回收得到一种重要的有机化工原料苯酚,不仅可以降低废水COD含量、减轻后续处理成本从而提高企业的经济效益,同时整个生产过程不会造成新的三废污染,具有良好的社会效益。试验研究表明,工艺上具有可行性。其中苯酚产品精馏回收率可达86.0%,产品质量可达99.5%以上,对羟基苯甲腈产品回收率可达90.0%以上,经济效益显著。

In the industrial production process of producing p-hydroxy benzonitrile from 4-hydroxybenzoic acid by amidation dehydration,a large amount of organic wastewater containing phenol will be produced.A series of pre-treatment will be carried out for it:sedimentation,extraction,acidification,rectification,distillation,etc.,and an important organic chemical raw material phenol will be recovered,which can not only reduce the COD content of wastewater and reduce the cost of subsequent treatment,thus improving the economic benefits of enterprises.At the same time,the entire production process will not cause new three waste pollution and has good social benefits.The experimental research shows that the process is feasible.Among them,the rectification recovery rate of phenol product can reach 86.0%,the product quality can reach more than 99.5%,and the recovery rate of p-hydroxy benzonitrile product can reach more than 90.0%,with significant economic benefits.