铝土矿酸性浸出液中铝、铁的回收

Recovery of aluminium and iron from acid leaching solution of bauxite

以铝土矿酸性浸出液为原料,通过化学沉淀、碱溶、碳分、煅烧等得到氧化铁和氧化铝粉体。考察了沉淀、碱溶、碳分过程中溶液终点pH值、反应温度、反应时间等参数的影响,得到优化工艺条件。结果表明,在终点pH值5.0、反应温度80℃、沉淀时间50min条件下进行沉淀,铝铁的沉淀率均达99%;在溶液终点pH值14、碱溶温度80℃、碱溶时间30min条件下,铝的溶出率可达99.42%,铁的去除率可达99.63%;在溶液终点pH值9.0、碳分温度40℃、CO2流速选择6mL/min条件下,铝的沉淀率可达98.69%。

Ferric oxide and alumina powder were obtained from bauxite acid leaching solution by chemical precipitation, alkali dissolution, carbon content and calcination. The effects of the end point pH value, reaction temperature and reaction time on the reaction rate in the process of precipitation, alkali dissolution and carbon content were investigated, and the optimum process conditions were obtained. The results show that the precipitation rate of aluminum and iron can reach 99% when the final pH value is 5.0, the reaction temperature is 80 ℃ and the reaction time is 50 min. Under the conditions of the final pH value 14, the alkali solution temperature 80 ℃ and the alkali solution time 30 min, the aluminum dissolution rate can reach 99.42%, the iron removal rate can reach 99.63%, the carbon removal rate can reach 99.63%. The precipitation rate of aluminum can reach 98.69% at endpoint pH value of solution 9.0, carbonating temperature as 40 ℃ and CO 2 flow rate 6 mL/min.