H_(2)O_(2)催化氧化缓释螯合铁离子处理碱性含氰废水的研究

Treatment of Alkaline Cyanide Wastewater by H_(2)O_(2) Catalytic Oxidation and Slow Release Chelated Iron Ions

黄金氰化过程中产生的废水多为碱性且含有大量亚铁氰络离子、铜氰络离子和游离氰根,为消除废水中氰化物对环境的污染并实现处置后废水回用,本文采用在弱碱性环境下引入EDDHA-Fe有机螯合铁离子并加入H_(2)O_(2)催化氧化方法分解氰根,同时氧化螯合剂释放铁离子形成普鲁士蓝沉降,实现对碱性废水中络合氰根进行了有效脱除。结果表明,在最佳实验条件下,滤液中氰化物沉淀去除效果显著,去除率达99.77%,滤液中总氰化物浓度由221.59mg/L下降至0.51mg/L,在不影响水体碱度的前提下有效实现了废水脱氰,处置后的废水可直接回用。

The waste water produced in the gold cyanidation process is mostly alkaline and contains a lot of ferrocyanide complex ions,copper cyanide complex ions and free cyanide.In order to eliminate the environmental pollution caused by cyanide in the waste water and realize the reuse of waste water after treatment,this paper introduces organic chelate iron ions(EDDHA-Fe)in a weak alkaline environment and adds H_(2)O_(2) to catalyze oxidation to decompose the cyanide,while oxidizing the chelating agent to release iron ions to form Prussian blue sedimentation,effective removal of complex cyanide ions from alkaline wastewater has been achieved.The results showed that under the optimal experimental conditions,the removal effect of cyanide precipitation in the filtrate was significant,with a removal rate of 99.77%.The total cyanide concentration in the filtrate decreased from 221.59 mg/L to 0.51 mg/L,effectively achieving wastewater decyanation without affecting the alkalinity of the water body.The treated wastewater can be directly reused.