逆流萃取回收废水中N,N-二甲基甲酰胺研究

Study on the Recovery of DMF from Wastewater by Countercurrent Extraction

为回收废水中的N,N-二甲基甲酰胺(DMF),作者以氯仿为萃取剂,在带筛板的夏倍尔萃取塔中进行逆流萃取实验,考察了萃取级数、搅拌转速、停留时间和溶剂比对DMF萃取效果的影响,得到了较佳的工艺条件:萃取级数为5级,搅拌转速为260~320 rpm,每级停留时间为15 min,溶剂比为2。在上述条件下,当废水中初始DMF含量在4%~5%时,萃余相中DMF含量低于0.1%。

To recover DMF from wastewater,countercurrent extraction experiments were performed in sieve plate Scheibel extraction column with choloroform as extractant.The effects of the number of stages,stirring speed,residence time and solvent ratio on DMF extraction performance were investigated and optimum conditions were obtained as follows:the number of stages was 5,the stirring speed was 260~320 rpm,the residence time per stage is 15 min and the solvent ratio was 2.Under the above conditions,the content of DMF in the raffinate was lower than 0.1%when the initial content of DMF in the wastewater was about 4%~5%.