碳化法纳米SiO_2表面结构研究  

Study on the Surface Structure of Silica Nanoparticles in Carbonation Process

作　　者：许雪冰 马艳丽[2] 李少鹏[2] 李会泉[2] 林荣毅[2] 田登超 张军[1] 

机构地区：[1]中国矿业大学(北京)化学与环境工程学院,北京100083 [2]中国科学院过程工程研究所湿法冶金清洁生产技术国家工程实验室,绿色过程与工程重点实验室,北京100190

出　　处：《硅酸盐通报》2015年第3期846-852,共7页Bulletin of the Chinese Ceramic Society

基　　金：国家科技支撑计划基金资助项目(2012BAF03B01);国家自然科学青年基金资助项目(51304184)

摘　　要：采用红外、热重、N2吸附等分析方法,研究了碳化法制备的纳米Si O2表面羟基、孔隙结构和吸油值等随陈化p H值、陈化时间及干燥温度的变化关系。实验结果表明,在不同陈化p H值下Si O2凝聚反应速率不同,陈化p H值由2升高到5,凝聚反应加快,颗粒表面羟基含量由1.54个/nm2减少到1.44个/nm2,平均孔径由11.51 nm增大到23.06 nm,吸油值由1.70 cm3/g升高到1.81 cm3/g;在不同陈化时间下Si O2颗粒间凝聚反应进程不同,陈化时间由10 min延长到90 min,颗粒表面羟基含量由1.48个/nm2减少到1.40个/nm2,平均孔径、吸油值变化不明显;在不同干燥温度下颗粒表面羟基脱除程度不同,干燥温度由100℃升高到500℃,表面羟基脱除增多,羟基含量由1.43个/nm2减少到0.70个/nm2,平均孔径由13.2 nm增加到41.07 nm,吸油值由1.82 cm3/g升高到2.00 cm3/g。The effects of aging pH, aging time and drying temperature on the surface hydroxyl groups, pore structure and DBP adsorption value in carbonation process were investigated. The results analyzed by FT-IR, TG, and N2 adsorption demonstrated that condensation reaction was affected by aging pH, while high pH would accelerate the condensation reaction and lead to low content of surface hydroxyl groups. When pH increased from 2 to 5, the number of surface hydroxyl groups reduced from 1.54/nm2 to 1. 44/ nm2, average pore diameter increased from 11.51 nm to 23.06 nm, and DBP absorption value increased from 1.70 cm3/g to 1.81 cm3/g. Aging time also had influence on the degree of condensation reaction. When the aging time increased from 10 min to 90 rain, the condensation process was completely reacted, while the number of surface hydroxyl groups reduced from 1.48/nm2 to 1.41/nm2 , average pore diameter and DBP absorption value had little change. In addition, when the drying temperature increased from 100 ℃ to 500 ℃ , the number of surface hydroxyl groups reduced from 1.43/nm2 to 0.70/nm2, average pore diameter increased from 13.2 nm to 41.07 nm, and DBP absorption value increased from 1.82 cm3/g to 2. 00 cm3/g

关 键 词：碳化法 纳米SI O2 表面羟基 孔隙结构 

分 类 号：TQ170[化学工程—硅酸盐工业]