表面改性剂在超细氢氧化镁过滤中的应用

摘要

以氯化镁为原料,氨水为沉淀剂,采用直接沉淀法制备了超细氢氧化镁,但超细氢氧化镁料浆的过滤性能差一直是制约氢氧化镁工业化生产的关键性问题之一.采用硬脂酸钠与水溶性钛磷酸脂偶联剂对超细氢氧化镁进行湿式改性实验,在改善超细氢氧化镁的表面性能的同时二者都能显著提高过滤性能.实验结果表明:采用固含率为15％的超细氢氧化镁悬浮液为原料,表面改性剂的最佳添加量为氢氧化镁粉体质量的2.00％.并以54框的BM70 - 800/25的板框式压滤机为例,对操作及生产能力进行了讨论.%Magnesium hydroxide was synthesized through direct precipitation method with MgCl2 as raw material and ammonia as precipitant. However,the bad filtration property of Mg( OH)2 slurry is the one of most difficult problems in the industrial production. Wet surface modification experiment for the superfine magnesium hydroxide was carried out with sodium stearate and titanium phosphate coupling agent,so that the surface and filtration properties could be both improved. Results showed that the superfine magnesium hydroxide slurry with solid concentration of 15% was adopted as raw material, and the best dosage of surface modifier was 2. 0% of magnesium hydroxide powder. In addition,the operation and production capacity were discussed by taking a BM70 - 800/25 plate filter press as example.