摘要：以硅灰石为原料,硫酸铝和硅酸钠为包覆剂,采用非均匀成核法制备一种硅酸铝-硅灰石复合粉体材料,研究搅拌速度、反应温度、反应时间、硫酸铝溶液浓度和滴加速度等工艺条件对复合粉体制备的影响。结果表明,控制机械搅拌速度为300~400 r/min,反应温度为80℃,反应时间为30 min,硫酸铝溶液浓度为0.1 mol/L,滴加速率为1~2 mL/min,可以实现硅酸铝以非均匀成核形式沉积在硅灰石表面,包覆硅酸铝后硅灰石白度提高,粒度增大,比表面积提高200%以上。

关键词：非均匀成核法；硅酸铝；硅灰石；复合粉体

Abstract：Taking wollastonite as raw materials,aluminum sulfate and sodium silicate as coating modifiers,a new type aluminum silicate-wollastonite composite powders was obtained by heterogeneous deposition method.The effect of processing parameters such as stirring speed,reaction temperature,reaction time,aluminum sulfate concentration and instill speed on preparing composite powders were investigated.It was shown that aluminum silicate successfully deposited on the surface of wollastonite particles by controlling the processing parameters that the stirring speed was 300~400 r/min,the reaction temperature was 80 ℃,the reaction time was 30 min,the concentration of aluminium sulfate was 0.1 mol/L and the instill speed was 1~2 mL/min.The whiteness of wollastonite powders increased,the particle size grew bigger and the specific surface area increased more than 200% after coated with aluminium silicate.

Keywords：heterogeneous deposition；aluminum silicate；wollastonite；composite powder