Abstract:

In order to analyze the influence of external factors on the preparation of polyferric sulfate,acid leaching reduction experiments and polymerization synthesis experiments under different conditions were carried out.The experimental condi-tions were optimized,and then the treatment effect of polyferric sulfate on contaminated water was analyzed under different pH,dosage of flocculating agent and settling times.The results showed that the optimal temperature of tailings all iron leaching experiments in acid leaching experiment was 100 ℃,the best stirring time was 2 h,and the best stirring speed was 300 r/min. The optimum reduction temperature of ferrous sulfate reduction rate in the reduction test was 60 °C,the optimal reduction time was 1.5 h,also the excess coefficient of reduced iron powder was 1.10%.The optimum polymerization temperature in the polymerization synthesis experiment was 35 ℃,and the prime polymerization time was 0.4 h.Under these conditions,polymerization effect was best at an n（hydrogen peroxide）∶n（Fe²⁺）∶n（sodium phosphate） ratio of 0.08∶1∶0.07.At neutral environment with pH of 7,the polyferric sulfate mass concentration of 2.0 g/mL and settling time of 0.3 h resulted in the smallest turbidity value and the best treatment effect for wastewater.

Key words: iron tailings, acid leaching reduction experiment, flocculant, polymeric ferric sulfate