针对氰化废水的特点,以三正辛胺(TOA)为载体、煤油为膜溶剂、液体石蜡为膜助剂、NaOH水溶液为内水相,采用乳状液膜技术处理工业废水中的氰化物。重点考察了表面活性剂用量、流动载体用量、内相液NaOH浓度等因素对氰化物萃取率的影响规律。研究结果表明:当TOA体积分数为2%、表面活性剂Span-80体积分数为3%、液体石蜡体积分数为1%、内水相NaOH质量分数为2%、油内比为1︰1、乳水比为1︰7、萃取时间为15min时,氰化废水中氰化物的萃取率达到95%以上。在实验得出的最优条件下,考察最优条件对初始浓度不同的实际废水的适用范围,分别对初始浓度为322.23mg/L、483.35mg/L、644.46mg/L和966.70mg/L的氰化废水进行处理,可得该体系下处理氰化废水的较佳的浓度范围为300~500mg/L,氰化废水中氰化物的萃取率可达到95%以上。综上所述,乳状液膜法在工业上具有良好的应用前景。
The cyanide wastewater was treated by emulsion liquid membrane method using three octyl amine(TOA) as carrier,kerosene as membrane solvent,liquid paraffin as membrane additives,and NaOH solution as aqueous phase. Cyanide extraction rate was influenced by surfactant dosage,mobile carrier dosage,and concentration of NaOH in the liquid phase. The experimental results showed that the extract rate of cyanide can reach above 95% in the following condition:2% of TOA volume fraction,3%of surfactant Span-80 volume fraction,1%of liquid paraffin volume fraction,2%of mass concentration of NaOH in the internal phase is,1∶1 of volume ratio of oil to internal phase is,1∶7 of volume ratio of emulsion liquid to wastewater,and 15 min of extraction time. Under the optimum condition,the different initial concentrations of cyanide wastewater of 322.23 mg/L,483.35 mg/L, 644.46 mg/L and 966.70 mg/L were studied in order to obtain the optimal range of the initial concentrations. The results showed that the extract rate of cyanide can reach above 95%when the rang of initial concentration of cyanide wastewater was 300-500 mg/L.