城市污泥中贵金属元素萃取分离体系的初步研究

Preliminary Study on the Extraction and Separation System of Precious Metal Elements from Municipal Sewage Sludge

在对拉萨市污泥样品中贵金属元素Au、Ag、Pt、Pd的含量测定的基础上,尝试采用不同萃取剂体系对污泥中这四种贵金属离子进行萃取分离。结果表明,拉萨市污泥中Au含量为(3.78±0.19)mg·kg^(-1),达到低品位金矿含量,有一定资源化价值;TBP-煤油、TBP-CHCl3、甲苯-四辛基溴化铵、丙二酸二乙酯、MIBK五种萃取体系对贵金属Au、Ag、Pt、Pd表现出不同的萃取效果,甲苯-四辛基溴化铵体系对四种离子的萃取率均高于其他萃取体系,甲苯-四辛基溴化铵对Au的萃取率可达99.24%。虽然MIBK体系萃取率稍低(99.07%),但其萃取液:水的相比较低,Au在萃取相中浓度较高,表现出较强的富集能力。

Based on the determination of Au, Ag, Pt and Pd in sewage sludge(SS) samples from Lhasa city, the extraction and separation of these four precious metal ions in SS with different extractant systems was attempted. The results showed that the Au content in SS in Lhasa city was(3.78±0.19) mg·kg^(-1), which reached the low grade gold content and had a certain resource value. TBP-kerosene, TBP-CHCl3, Toluene-tetraoctyl ammonium bromide, diethyl malonate and MIBK showed different extraction effects on precious metals Au, Ag, Pt and Pd, and Toluene-tetraoctyl ammonium bromide had higher extraction rates for the four ions than other extraction systems. The extraction efficiency of Toluene-tetroctylammonium bromide for Au can reach 99.24 %. Although the extraction rate of MIBK system is slightly lower(99.07 %), its extraction liquid: water ratio is low, and Au concentration in the extraction phase is high, showing a strong enrichment ability.