铁粉预还原—硫化亚铁脱除高酸性硫酸铁溶液中的砷

焙烧氰化法提金尾渣经酸浸后产出大量酸性硫酸铁溶液,因其中含有较高的砷而限制了其高值化利用。采用铁粉预还原—硫化亚铁脱砷对溶液中的砷进行脱除研究。结果表明,溶液中砷的存在形式及分布与溶液体系电位密切相关,铁粉可以有效降低溶液电位,经铁粉预还原后硫酸铁溶液中的砷可用硫化亚铁有效脱除。当铁粉添加量为溶液中铁含量的0.6倍,溶液加入36.6g/L的FeS,搅拌30min,可使溶液中砷含量由0.253g/L降低至4.79mg/L。空气对脱砷过程有不利影响。

Removal of Arsenic from High Acid Ferric Sulfate Solution by Iron Powder Pre-reduction and Ferrous Sulfide Dearsenization

A large amount of acid ferric sulfate solution is produced after acid leaching of gold tailings from roasting cyanidation process. Its high value utilization is limited because of its high arsenic content. Method to remove arsenic by iron powder pre-reduction and ferrous sulfide dearsenization was investigated. The results show that existing form and distribution of arsenic in solution are closely related to potential of solution system, and iron powder can effectively reduce potential of solution. Arsenic in ferric sulfate solution after pre-reduction with iron powder can be effectively removed by ferrous sulfide. When amount of iron powder is 0.6 times of iron content in solution, arsenic content in solution can be reduced from 0.253 g/L to 4.79 mg/L after adding 36.6 g/L FeS into solution and stirring for 30 min. Air has an adverse effect on arsenic removal process.