赤泥制备聚合氯化铝铁及其吸附性能研究

Preparation and Adsorption Properties of Polyaluminum Ferric Chloride from Red Mud

利用赤泥盐酸浸出所得酸浸液制备了聚合氯化铝铁(PAFC),并对其处理高岭土废水的性能进行了研究。考察了盐酸浓度、浸出温度、浸出时间和液固比对赤泥中Al、Fe浸出率的影响,及PAFC投加量、高岭土质量浓度、废水pH值和水温对PAFC处理污水时高岭土浊度去除率的影响。实验结果表明:在盐酸体积浓度50%,浸出温度80℃,浸出时间1.5 h和液固比5 mL/g的条件下,赤泥中Al浸出率为76.5%,Fe浸出率为33.7%。在PAC/PAFC投加量为8 mL(10 g/L),废水pH值为7.0,高岭土悬浊液(质量浓度为125 mg/L)体积为500 mL,废水温度20℃的条件下,PAC的最高去浊率达90%,而自制PAFC的最高去浊率达94%。

Polyaluminum ferric chloride(PAFC) was prepared from acid leaching solution obtained by hydrochloric acid leaching of red mud,and its performance of kaolin wastewater treatment was studied.The effects of hydrochloric acid concentration,leaching temperature,leaching time and liquid-solid ratio on the leaching rate of Al and Fe in red mud were investigated.Also the effects of PAFC dosage,kaolin quality concentration,wastewater pH value and water temperature on the turbidity removal rate of kaolin during wastewater treatment with PAFC were studied.The experimental results show that the leaching rate of Al and Fe is 76.5% and 33.7%,respectively,under the conditions of 50% hydrochloric acid concentration,80 ℃ leaching temperature,1.5 h leaching time and 5 mL/g liquid-solid ratio.The highest turbidity removal rate of PAC for kaolin wastewater treatment is 90%,while that of self-made PAFC is 94%,under the conditions of PAC/PAFC dosage of 8 mL(10 g/L),wastewater pH value of 7.0,kaolin suspension(mass concentration 125 mg/L) volume of 500 mL and wastewater temperature of 20 ℃.