二次铝灰制备聚合氯化铝试验研究

二次铝灰是再生铝工业生产中的主要副产物之一,成分复杂,含盐量高.襄阳某再生铝厂二次铝灰产量巨大,长期堆存对环境构成一定的威胁.为减轻二次铝灰对环境的污染,实现二次铝灰的高值化利用,采用水洗—酸浸—聚合熟化工艺制备聚合氯化铝.试验考察了聚合温度、聚合时间、聚合pH值等条件对聚合氯化铝中氧化铝含量和盐基度的影响,并对优化条...

Experiment Study on the Preparation of Polyaluminum Chloride with Secondary Aluminum Dross

Secondary aluminum dross is a main by-product of aluminum industrial production with complex composition and high salt content. The output of secondary aluminum dross in a secondary aluminum plant in Xiangyang is huge， and long-term storage poses a certain threat to the environment. In order to reduce the pollution to the environment and realize the high-value utilization of secondary aluminum dross，polyaluminum chloride was prepared by process of water washing pretreatment， hydrochloric acid leaching and polymerization maturing.The effects of polymerization temperature， polymerization time， polymerization pH value on the alumina contents and basicity of polyaluminum chloride were investigated， and the polyaluminum chloride prepared under optimized conditions was characterized by XRD， scanning electron microscopy and infrared spectrum. The results showed that the production prepared under the optimized conditions of polymerization temperature of 70 ℃， polymerization time of 5 h and polymerization pH of 3.0 displayed alumina contents and basicity of 9.09% and 46.30%， respectively.All indicators of the product were up to the national quality standards. The XRD and scanning electron microscopy analysis showed that the contents of metal impurities in the synthesized polyaluminum chloride was relatively low， and the main substance was sodium chloride. The infrared spectrum indicated that hydroxyl and polymeric aluminum were presented in the polyaluminum chloride molecule.