采用压缩空气和双氧水作氧化剂,通过控制氧氧化钠体系中的电位来氧化浸出铅阳极泥中的砷.试验中考察电位、NaOH浓度、反应温度、反应时间和液固质量比对脱砷效果的影响,确定碱性浸出过程中预脱砷的最佳工艺条件:NaOH浓度为2 mol/L,温度为80℃,液固质量比为5∶1,通入0.2 MPa的压缩空气4h后用双氧水调节体系的电位至-180 mV,反应时间为2h.在此条件下,砷的浸出率可达98％以上.碱浸液经冷却过滤掉结晶砷酸钠后,返回浸出过程,砷的浸出率达98％以上,实现碱浸液的循环利用以及砷与其他金属的有效分离.%Arsenic was leached from lead anode slime with the oxidants including compressed air and hydrogen peroxide by potential control in sodium hydroxide system. The effects of potential, concentration of sodium hydroxide, reaction temperature, reaction time and solid/liquid ratio on arsenic removal were investigated and the optimum conditions of the arsenic removal in the alkaline leaching process were determined as follows: NaOH concentration of 2 mol/L, reaction temperature at 80 ℃, solid/liquid ratio of 5:1, 0.2 MPa compressed air into reaction system for 4 h, controlling the potential at -180 mV, and reaction time for 2 h. More than 98% of the amount arsenic is removed under these conditions. The alkaline leaching solution is returned to leaching process after the removal of crystal sodium arsenate by cooling and filtration, which achieves the recycling of alkaline solution and the effective separation of arsenic from other metals.
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