以水玻璃为硅源喷雾干燥制备SiC前驱体  

Preparation of precursor for silicon carbide by using water glass as silicon sources

作　　者：潘顺龙[1] 张敬杰[1] 杨岩峰[1] 宋广智[1] 

机构地区：[1]中国科学院理化技术研究所,北京100101

出　　处：《耐火材料》2006年第3期213-216,共4页Refractories

摘　　要：以廉价的水玻璃和炭黑为原料,通过制备均匀混合的前驱体,利用碳热还原反应合成出超细SiC粉体。比较研究了前驱体喷雾干燥与搅拌干燥两种制备方法对体系碳热还原反应的影响,重点考察了喷雾干燥制备过程中主要工艺参数对前驱粉体密度及收率的影响。结果表明:喷雾制备的前驱体具有更高的反应活性,在1550℃下反应2h就可使SiO2转化率达到89.4%,搅拌干燥制备的前驱体转化率只有65.2%。喷雾干燥过程中,适当提高进口温度、喷雾头转速并降低料液的固体含量,可获得高收率、高产率的前驱粉体,利于整个制备工艺生产效率及产率的提高。Ultrafine silicon carbide powder was synthesized by carbothermal reduction of precursor prepared by drying slurry of water glass and carbon black. The effects of drying methods, spray-drying and mixingdrying on carbothermal reduction were studied. The influences of primary technical indicators of spraydrying process on apparent density and yield rate of the precursor were also analyzed. It was indicated that the spray-dried precursor is more reactive than the mixing-dried. The conversion rate of spray-dried SiO2 precursor was 89.4% and that of the mix dried 65.2% at 1550 ℃ for 2 h. To increase the yield rate of precursor in spray-drying reasonable increase of inlet temperature and rotation rate of spray driver and decrease of solid content of the slurry are required.

关 键 词：SIC 水玻璃 碳热还原 喷雾干燥 

分 类 号：TQ174.758[化学工程—陶瓷工业] TQ051.892[化学工程—硅酸盐工业]