二烷基亚砜—胺二元系从氰化物溶液中萃取金

Extraction of Gold (I) from Cyanide Solution by Sulfoxide—Amine Mixture in n-Dodecane

研究了二烷基亚矾—胺从氰化物溶液中萃取金的反应中,亚矾和胺的化学结构以及萃取条件对萃金效果的影响。结果表明二烷基亚砜—仲胺体系在适当条件下可从较高pH(10～11)的氰化物溶液中有效地萃取金,并能与大多数共存金属元素达到很好的分离。此外,还具易于反萃的优点,是有应用前景的新型萃取体系。

Extraction of gold (Ⅰ) from cyanide solution with binary sulfoxideamine systems was studied. The influence of the structure of sulfoxides, the concentration of sulfoxide and amine, as well as the pH of the cyanide solution on the extraction behaviour were illustrated. The extraction ability of amine is increased in the following order: tertiary <primary < secondary. Dialkylsuliide with normal or r-branchedalkyl group is favourable in gold extraction. Based on the those observations some new extraction systems were developed, such as 40% di- 2 -ethyl-hexyi sulfoxide-0.1mol/L amine-dodecane system, by which the pH_(0.5) of gold extraction was achieved at pH 11, and all base metals including Cu, Zn, and Fe remained in the aqueous solutuon. Meanwhile, gold is easily stripped from organic phase by 0.1mol/L NaOH solution.