溶剂萃取富集回收金矿氰化废水中铜氰络合离子的研究

采用三辛基甲基氯化铵(N263)-磷酸三丁酯(TBP)-正辛醇-磺化煤油协同萃取体系从金矿氰化废水中富集和回收有价金属，主要研究了N263与TBP的浓度、振荡时间、水相初始pH、相比(O/A)对铜氰络合离子萃取率的影响及协同萃取反应机制。研究表明，采用N263(20 vol.%)-TBP(15 vol.%)-正辛醇（10 vol.%）-磺化煤油体系在室温，O/A为1:1，pH值为10、混相时间为5min的条件下，废水中铜离子的单级萃取率可达到为98.9%，饱和萃取容量为19576 mg/L。饱和负载有机相经1 mol/L NaOH+5 mol/L NaSCN溶液反萃，在相比（O/A）为2:1的条件下，单级反萃液中Cu离子浓度可达到23000 mg/L，实现了废水中铜氰络合离子的有效富集。萃取过程中铜氰络合离子优先与TBP结合从而失去亲水性，随后再与N263阳离子发生离子缔合反应进入有机相。

Solvent extraction for the enrichment and recovery of copper-cyanide complex ions from gold ore cyanidation wastewater

A trioctylmethylammonium chloride (N263)-tributyl phosphate (TBP)-n-octanol-sulfonated paraffin synergistic extraction system was used to enrich and recover valuable metals from gold mine cyanide wastewater. The effects of the concentrations of N263 and TBP, oscillation time, initial pH of the aqueous phase, compared to (O/A) on the extraction rate of copper-cyanide complex ions and the synergistic extraction reaction mechanism were mainly investigated. It was shown that the single-stage extraction rate of copper ions in wastewater could reach 98.9% with a saturation extraction capacity of 19576 mg/L using the N263 (20 vol.%)-TBP (15 vol.%)-octanol (10 vol.%)-sulphonated paraffin system at room temperature, O/A of 1:1, pH of 10 and a mixing time of 5 min. The saturation loading The organic phase was reverse extracted by 1 mol/L NaOH + 5 mol/L NaSCN solution, and the concentration of Cu ions in the single-stage reverse extract solution could reach 23000 mg/L under the condition of 2:1 compared to (O/A), which achieved the effective enrichment of Cu-cyanide complex ions in the wastewater. During the extraction process, the Cu-cyanide complex ions are preferentially bound to TBP and thus lose their hydrophilicity, followed by ionic association with N263 cations into the organic phase.