稻壳微波制备高纯白炭黑的工艺研究

Study on the preparation of silica from rice husk using microwave heating

采用微波反应方式,将稻壳与氢氧化钠反应获得硅酸钠溶液(水玻璃),采用沉淀法制取高品质白炭黑。以白炭黑对邻苯二甲酸二丁酯的吸收值为指标,研究了水玻璃模数、反应终点p H、反应温度对白炭黑比表面积的影响。结果表明,采用1 mol/L的H_2SO_4溶液对其滴定,当反应终点pH值为10,水玻璃模数为2.2,反应温度为95℃时,制备出的白炭黑品质最好,其对邻苯二甲酸二丁酯吸收值可达3.779 m L/g。

Using the rice husk as the silicon source and microwave heating,the sodium silicate solution were obtained by the reaction with sodium hydroxide and the silica was prepared using the precipitation method. The influences of process conditions such as deliquescent rate of SiO2,pH of reaction end point and reaction temperature on the surface area were studied. Result showed that using the 1 mol / L H2SO4,for the pH = 10,the deliquescent rate as 2. 2 and temperature is 95 ℃,the silica has the best quality with in DBP oil absorbed value as 3. 779 m L / g.