LAUSR

The bottleneck of strontium compounds preparing from celestite is the promotion of Sr/S isolation efficiency. Low energy consumption and zero release method for isolating Sr/S in preparing Sr(OH)2 process from celestite in mild condition was described. Sr element remained in precipitation with formation of Sr(OH)2, while S element entered into leachate with formation of Na2SO4. The effects of initial concentration of NaOH, conversion temperature, liquid-to-solid (L/S) ratio and conversion time on Sr/S ratio of samples for celestite conversion were systematically investigated by experiments. The results demonstrated that the efficiency of Sr/S isolation increased with the initial concentration of NaOH, L/S ratio and conversion time, and decreased with conversion temperature. The maximum conversion ratio of Sr(OH)2 was 93.88% under the optimum condition, whose Sr/S ratio of sample could reach to 41.16. It illustrated that better isolation efficiency of celestite could be achieved in alkaline treatment. The results of SEM-EDS analyses demonstrated that the conversion reaction was a dissolution-precipitation process.摘要天青石制备其他锶化合物的瓶颈在于如何实现Sr/S 元素的高效分离。本文针对天青石转化 Sr(OH)2 过程中的Sr/S 元素高效分离进行研究,开发出一种低能耗及零污染的Sr/S 元素分离新方法, 其中Sr 元素以Sr(OH)2 形式存在于固相中,S 元素则以Na2SO4 形式进入液相中。通过对反应过程中 的因素,如初始NaOH 浓度、转化温度、液固比和转化时间对Sr/S 元素分离效率的影响进行的研究, 结果发现Sr/S 元素的分离效率随着初始NaOH 浓度、液固比和反应时间的增大而增加,而随着反应 温度的升高而降低。在所得最优转化条件下,Sr(OH)2 的最大转化率可达93.88%,该样品中的Sr/S 比 可达到41.16。这证实了在碱性溶液中天青石转化成Sr(OH)2 过程可以较好地实现Sr/S 的高效分离。 样品的SEM-EDS 测试结果表明其转化过程为溶解-沉积过程。