从工业废水中回收乙酸的方法研究进展

A review on recovery technologies of acetic acid from industrial wastewater

随着我国工业水平的不断提高，含有乙酸的废水产生量越来越大。乙酸的含量一般在1%～30%（质量分数），使废水不仅表现为强酸性，而且化学耗氧量高，不易直接排放。乙酸与水不易分离也使乙酸废水在工业上难以处理，研究从废水中回收乙酸的方法具有重要意义。本文简要介绍了近几年国内外从工业废水中回收乙酸的进展，主要包括膜分离法、吸附法、萃取法、萃取酯化法、精馏法，并分析了每种方法的优缺点以及当前的研究水平。指出：双极膜电渗析和渗透汽化法适合乙酸质量分数在1%左右的废水处理；吸附法和反应萃取法适用于乙酸含量在10%以下的废水处理，30%以下的乙酸废水可以借助反应精馏进行分离。最后分析了膜分离法和吸附法处理含乙酸废水的工业应用尚需解决的关键问题。

Increasing industrial wastewater containing acetic acids in has been a concern. Acetic acid ranged from 1%-30%by weight,causing strong acidity in wastewater and high chemical oxidation demand,which makes it infeasible to discharge directly. It is also difficult to separate acetic acid from wastewater. This paper reviewed the wastewater acetic acid recovery technologies , including membrane separation,adsorption,extraction,extractive esterification and distillation. Both advantages and disadvantages of these technologies and current research progresses were also discussed. Research indicated that bipolar membrane electrodialysis and pervaporation are suitable to deal with the wastewater with 1% acetic acid;adsorption and reactive extraction are fit for 10% acetic acid wastewater;wastewater with 30%acetic acid can be handled on the support of reactive distillation;extractive distillation is more used for acetic acid solutions beyond 35%. This paper also analyzed the existing problems in membrane separation and adsorption for the disposal of acetic acid wastewater .