新型萃取剂从废旧CPU中萃取金的性能研究

Properties of a New Extraction Agent Extracting Gold from Waste CPU

研究了以新型的醚类有机相GA108为萃取剂,从废旧CPU中萃取金的过程;辅助一些热力学计算,考察分析了萃取时间t、相比O/A、母液氢离子浓度CH+、金离子浓度CAu3+、萃取温度T、萃取级数等萃取条件对GA108萃取性能的影响。结果表明:GA108萃取性能优良,具有快速、高效的萃取特点,3 min即可达到萃取平衡;相比和氢离子浓度分别在O/A=1∶3～1∶2,CH+=0.5～1.5 mol·L-1区间时,萃取性能恶化,应尽量避免该区间;萃取金离子浓度在700～1200 mg·L-1范围内萃取效果最好,实验结果说明,该萃取剂GA108适合高品位金的萃取;萃取反应为放热反应(ΔH=-17.11 kJ·mol-1<0),萃取过程宜在室温下进行;随萃取级数增加,萃取率增大。其最佳萃取条件为:T=25℃,t=3 min,CH+=4 mol·L-1,CAu3+=700～1200 mg·L-1,O/A=2∶1,二级萃取,在此萃取条件下,金萃取率可达到99.7%以上。

The extraction behavior of gold with a new type of ether organic GA108 from waste CPU was studied. Assisted by thermo- dynamic analysis, the influence of time, phase ratio of extraction O/A, hydrogen ion concentration, initial gold iron concentration, ex- traction temperature and extraction stage on gold distribution ratio and extraction rate were studied. The results showed that GA108 had a good extraction performance with a fast and efficient characteristics, and the equilibration could be reached in only 3 min. When the phase ratio of extraction O/A was 1： 3 to 1 ： 2 and hydrogen ion concentration was 0.5 to 1.5 mol .L - 1, the extraction rate deteriorated, and this range should be avoided. The appropriate initial gold iron concentration was 700 to 1200 mg.L-1 , the results indicated that GA108 was more suitable for high grade gold concentration extraction; the extractive reaction was an exothermic reaction （ AH = -17.11 kJ-mo1-1 〈0）, so the appropriate temperature to react was in room temperature. The more the number of extraction stages was, the higher the extraction rate was. The optimum parameters in the solvent extraction process were as follows： room temperature, time of 3 min, hydrogen ion concentration of 4 mol.L-1 ,