硅–铝溶胶作为耐火浇注料胶结剂的研究现状与展望  

Recent Development and Prospects on Silica–Alumina Colloidal Bonded Refractory Castables

作　　者：王玉龙[1] 李享成[1] 陈平安[1] 朱伯铨[1] 

机构地区：[1]武汉科技大学耐火材料与冶金国家重点实验室,武汉430081

出　　处：《硅酸盐学报》2017年第3期422-432,共11页Journal of The Chinese Ceramic Society

基　　金：国家自然科学基金(51374162);湖北省自然科学基金重点项目(2014CFA091)资助

摘　　要：对比介绍了几种浇注料结合系统、铝酸钙水泥作为浇注料结合剂的优缺点以及溶胶结合剂替代铝酸钙水泥的趋势。对硅溶胶和铝溶胶的硬化机理进行了着重分析,硅溶胶的胶凝化与硅氧烷的形成密切相关,可通过改变pH值、添加硬化剂、干燥、冰冻等方式实现硅溶胶胶凝化,而铝溶胶的胶凝化主要通过改变pH值、改变离子强度、改变温度来实现。同时介绍了显著影响浇注料施工性能的分散剂的分散机理和研究现状,突出了硅溶胶结合浇注料中分散剂的作用特点,在偏碱性浇注料中硅溶胶颗粒表面会带有强烈的负电荷,为提高分散剂在硅溶胶颗粒表面的吸附量,可以选择具有较高pK_a官能团的分散剂。评述了溶胶结合剂在浇注料中应用的优势,主要体现在可以更快更安全的干燥、具有更高的烧结性、体积稳定性好、中温强度高、高温机械性能更好等优点。最后预期了溶胶作为浇注料结合剂其未来的研究重点。This review briefly introduces the different binding systems for refractory castables, and represents the benefits of replacing calcium aluminate cement by colloidal binders. The setting mechanisms of colloidal bonded castables were reviewed for effective control of the setting process. The gelling of silica colloids is closely related to the formation of siloxane network. The suspension of silica colloids is commonly destabilized by controlling the pH value, addition of setting agents, drying the suspension and freezing the sol. The suspension of alumina colloids is commonly destabilized by controlling the pH value, changing the ionic strength and temperature. The use of dispersions in colloidal bonded castables was introduced, highlighting the difference of dispersing mechanism in colloidal systems. The surface of silica colloids in slightly alkaline castables system has negative charge, thus selecting the dispersant with a higher pKa value for greater adsorption. The advantages of silica/alumina colloids as a refractory binder were described including a faster drying, a higher sinterability, a superior mechanical strength at intermediate temperatures, better thermomechanical properties at high temperatures. In addition, the future studies on the colloidal bonded refractory castables were also outlined.

关 键 词：溶胶结合剂 浇注料 应用 展望 

分 类 号：TQ175.79[化学工程—硅酸盐工业]