二次铝灰制备低铁硫酸铝工艺研究

The Technique to Prepare Aluminium Sulfate in Low Iron Using Secondary Aluminum Ash

本文以固体二次铝灰为主要原料,通过预处理、酸浸、除铁、浓缩蒸发得到低铁硫酸铝,浸出过程重点考察了浸出时间、温度、酸浓度、配料比等实验条件对铝的浸出率的影响,浸出后采用亚铁氰化钾沉淀法除铁,主要考察了配料比对除铁效果的影响。当硫酸浓度25%~30%(质量分数),反应温度100℃,浸出时间6 h,铝灰的铝提取率可达到76%。除铁配料比达到1.4时,除铁效果达到98%,Fe含量仅为0.005%,可得到低铁硫酸铝产品。

This paper takes solid secondary aluminum ash as the main raw material to obtain aluminium sulfate in low iron by pretreatment, acid leaching, iron removal and concentrated evaporation. The effects of leaching time, temperature, acid concentration and proportion on the leaching rate of aluminum were investigated. The influence of the ingredient ratio on the iron removal efficiency was investigated by using potassium ferrocyanide precipitation method. When proportion of concentrated sulfuric acid was 25 %-30 % （mass traction）, reaction temperature 100℃, leaching time, 6 h, aluminum ash of extraction rate can reach 76. When the iron ingredient ratio reaches 1.4, the iron removal efficiency reaches 98 %, the Fc content is only 0.005 %, and the aluminum sulfate in low iron products are obtained.