关键词: 含硫酸亚铁废溶液, 嗜酸性氧化亚铁硫杆菌, H₂S去除, Fe²⁺氧化, 溶解性Fe³⁺, 沉淀

Abstract: Acidithiobacillus ferroxidans was used to oxidize Fe²⁺ into Fe³⁺ in the ferrisulfas liquor, and then dissolved Fe³⁺ was reduced by H₂S, achieving both reclamation of the liquor and removal of H₂S. The key factor for the removal efficiency of this treatment system was high concentration of dissolved Fe³⁺. However, when NH₄⁺ and K⁺ were excessive, most portions of dissolved Fe³⁺ would be transferred into Jarosite. The nitrogen source was optimized to obtain high concentration of Fe³⁺ by controlling its ingredients and concentrations. It showed that (NH₄)₂HPO₄ could replace (NH₄)₂SO₄ to be the nitrogen source and its concentration in 0.33-1 g·L^-1 was a suitable range for cell growth of Acidithiobacillus ferroxidans. At 1 g·L^-1, the bacterial growth did not exhibit obvious lag period; average oxidation rate of Fe²⁺ was 0.221-0.229 g·(L·h)^-1, dissolved Fe³⁺ increased to 7.62-7.72 g·L^-1, and precipitation was 1.17 g·L^-1. Therefore, the optimal concentration of (NH₄)₂HPO₄ was 1 g·L^-1. In order to reduce cost, the concentration was lowered 0.33 g·L^-1. This technique not only maintained the Fe²⁺ oxidative activity of Acidithiobacillus ferroxidans but also effectively increased dissolved Fe³⁺ produced during bacterial culture process, providing scientific optimization basis for removal of H₂S by the ferrisulfas liquor.

Key words: ferrisulfas liquor, Acidithiobacillus ferroxidans, H₂S removal, Fe²⁺ oxidation, dissolved Fe³⁺, precipitation