中文摘要：

研究了微硅粉在氢氧化钠溶液中的碱溶行为和反应动力学。采用X射线荧光光谱（XRF）、X射线衍射（XRD）、红外光谱（FT-IR）和扫描电镜（SEM）等对微硅粉进行了表征分析。通过正交实验和单因素实验相结合分析了反应温度、反应时间、初始氢氧化钠浓度和灰碱比对微硅粉中二氧化硅溶出率的影响;采用＂等高切面法＂分析计算了微硅粉的碱溶反应动力学参数。结果表明：反应温度和碱浓度对碱溶反应的影响最为显著;微硅粉碱溶脱硅的最优工艺条件为反应温度120℃、反应时间60 min、初始氢氧化钠浓度10%、灰碱比为0.89,在此条件下,二氧化硅的溶出率为91.5%,微硅粉碱溶脱硅反应的表观活化能为16.21 k J·mol^-1,反应级数为1。

英文摘要：

The dissolution behavior and reaction kinetics of fine silica powder were investigated. The fine silica powder was characterized by X-ray fluorescence（ XRF）,X-ray diffraction（ XRD）,Fourier-transform infrared（ FT-IR） spectroscopy,and scanning electron microscopy（ SEM）. The effect of reaction temperature,reaction time,initial concentration of NaOH,and the mass ratio of silica powder to alkali on the dissolution rate of SiO_2 were analyzed. The reaction kinetics parameters of fine silica powder were calculated using the contour section method. The results show that the optimal process conditions are： reaction temperature of 120 ℃,reaction time of 90 min,initial NaOH concentration of 10%,and mass ratio of ash to alkali of 0. 89. The SiO_2 dissolution rate reached 91. 5%. The order of the influence of the reaction conditions on the dissolution rate of SiO_2 was： initial concentration of NaOH,ratio of ash to alkali,reaction temperature,and reaction time. The dissolution apparent activation energy of silica powder in alkali solution was 16. 21 k J·mol^-1,and the reaction progression was 1.