从分银渣的盐酸浸出液中回收和制备氧化铋

铜阳极泥分银渣盐酸浸出液中含锑、锡、铅、铋等,采用水解除锡和锑、硫酸盐沉铅、一次水解沉铋等分步沉淀工艺,进行锑、锡、铅、铋的分离并得到粗氯氧铋。结果表明,在pH 1.4左右进行锑、锡水解,pH 2.1进行铋一次水解。粗氯氧铋经盐酸返溶后,控制pH 1.6~1.7进行铋二次水解产出精制氯氧铋,然后再碱转,即可制备出纯度大于99.9%的氧化铋。

Recovery and Preparation of Bismuth Oxide from Hydrochloric Acid Leaching Solution of Silver-separation Slag

Hydrochloric acid leaching solution of silver-separation slag from copper anode slime contained antimony, tin, lead, and bismuth, and etc. Bismuth was separated from the above solution by fractional precipitation process to prepare crude bismuth oxychloride, i.e., removal of antimony and tin by hydrolysis precipitation at about pH 1.4, lead precipitation with sulphate, and bismuth hydrolysis precipitation at about pH 2.1. The crude bismuth oxychloride was refined by dissolving in hydrochloric acid and secondly bismuth precipitation at pH 1.6~1.7 to produce purified bismuth oxychloride. Bismuth oxide with grade of 99.9% above was prepared by treating the purified bismuth oxychloride in sodium hydroxide solution.