Abstract:According to the characteristics of arsenic, nickel and high acid in the mother liquor of copper sulfate crystal, the industrial experiments of neutralization, copper and nickel sedimentation were carried out successively by pH value regulation method according to orthogonal experiment, and the effects of reaction time and pH value on separation effect were investigated. The results show that copper, arsenic and nickel can be recovered effectively by adjusting pH value of mother liquor with liquid alkali. The optimum parameters of neutralization reaction are as follows: terminal pH value of 2.5—3.0, reaction time of 1.5 h, natural temperature rise, more than 98% of arsenic can be recovered in the form of copper-arsenic slag, and successfully separated from nickel; The precipitation rate of copper is >93% when the final pH value of copper precipitation reaction is 6.0—6.5, the reaction time is 1.0 h, and the reaction temperature is 80—90 ℃; The pH of the end point of nickel precipitation reaction is 10.0—10.5, the reaction time is 2.0 h, and the nickel precipitation rate is >98% at room temperature. The mother liquor of nickel precipitation after treatment contains copper <50 mg/L, arsenic <5 mg/L, nickel <100 mg/L, the mother liquor has been effectively treated. The copper recovery rate is >96%, the arsenic recovery rate is >98%, and the nickel recovery rate is >84%.