羟基乙酸生产废水的资源化研究

Utilization of Wastewater from the Production of Glycolic Acid

采用浓缩结晶法回收羟基乙酸生产废水中的硫酸铵.研究了脱水率对硫酸铵回收率及硫酸铵晶体中羟基乙酸的吸附损失等的影响,确定了适宜的回收工艺条件;以PCW-6为萃取剂,采用络合萃取法回收废水中的羟基乙酸,探讨了各因素(酸度、络合剂浓度、油水比、温度、萃取平衡时间)对羟基乙酸萃取率的影响;确定以NaOH溶液作为反萃剂,讨论了萃取剂用量对反萃率的影响等,确定和优化了萃取和反萃的工艺条件.结果表明,在本研究的最佳工艺条件下,硫酸铵的总回收率接近100%,羟基乙酸的回收率可达92%.

Applying concentrated crystallization process to reclaim ammonium sulfate from the wastewater from the production of glycolic acid, the paper studied the effects of dehydration ratio to the recovery of ammonium sulfate and absorption loss of glycolic acid in ammonium sulfate crystal, and ascertained the fitting recovering technical conditions, By way of complex extraction with PCW-6 extractant to recover glycolic acid from the wastewater, the paper discussed different effects of each factor （ such as acidity, extractant concentration, oil-water ratio, temperature, and equilibrium time） to the extracting efficiency. Using NaOH solution as stripping agent, the paper studied the effect of NaOH dosage to the stripping efficiency and so on, and ascertained and optimized the experimental conditions. The result shows that under the ascertained conditions the recovery of ammonium sulfate approximates to 100%, and the percent recovery of glycolic acid comes to 92%.