四氯化硅气相水解制备超细白炭黑工艺的研究

Study on Preparation Technology of Ultrafine Silica by Silicon Tetrachloride Gas Phase Hydrolysis Method

本文以四氯化硅为原料,采用气相水解法制备超细白炭黑新工艺。探讨了四氯化硅通气速率、硅酸钠含量及反应温度等因素对产物理化性能的影响。结果表明,较优工艺条件为四氯化硅通气速率150 mL/min,硅酸钠含量13%,反应温度70℃。该工艺条件下所得产物为无定形结构超细白炭黑,其吸油值2.57 mL/g,比表面积115.49m2/g,二氧化硅含量(干基)99.06%,表观密度0.11 g/mL,粒径(d50)6.5μm。

The ultrafine silica was prepared from silicon tetrachloride by gas phase hydrolysis method in this paper.Several reaction factors such as the ventilation rate of silicon tetrachloride,concent of Na2SiO3 and reaction temperature on the physical and chemical properties of product were investigated.The results show that the optimum conditions are confirmed as follows： ventilation rate of silicon tetrachloride is 150 mL/min,concent of Na2SiO3 is 13% and reaction temperature is 70 ℃.Under the optimum conditions,the product is amorphous silica and characterized in various aspects as follows： DBP is 2.57 mL/g,specific surface area is 115.49 m2/g,silica content（dry basis） is 99.06%,apparent density is 0.11 g/mL and particle size（d50） is 6.5 μm.