摘要
以汉白玉废料为起始原料,利用化学方法合成纳米碳酸钙粉体,为了获得无团聚、特性好的碳酸钙粉体,探讨了4种干燥方式:冷冻干燥、真空干燥、喷雾干燥、普通烘箱干燥对纳米碳酸钙粉体形成硬团聚的影响;并用平均粒度、BET和TEM法对制得的纳米碳酸钙粉体进行表征,实验结果表明:冷冻干燥和真空干燥都能防止纳米碳酸钙粉体形成硬团聚,其中冷冻干燥效果更显著,得到的碳酸钙粉体平均粒径为70nm,且分布均匀,比表面积大,冷冻干燥是最好的沉淀干燥方式;经喷雾干燥和烘箱干燥的碳酸钙粉体团聚现象严重,不适宜纳米碳酸钙干燥。同时分析了4种干燥方式中纳米碳酸钙粉体硬团聚形成的原理。
The nanosized calcium carbonate was produced by chemosynthesis with marble as raw material, and the effects of drying processes on the formation of hard agglomerates in nanosized calcium carbonate were studied. The nanosized calcium carbonate powders were characterized by average particle diameter, BET and TEM method. Experiments indicate that among the four kinds of drying processes considered in the paper, both freeze drying and vacuum drying can prevent the nanosized calcium carbonate from forming hard agglomerates, while the former is more effective. The calcium carbonate powder obtained by freeze process has a uniform grain size and large specific surface area, with average particle diameter of 70 nm. The other two processes, spray drying and oven drying, are found to result in serious agglomeration. The agglomeration mechanisms of nanosized calcium carbonate in the four drying processes were also discussed.
出处
《四川大学学报（工程科学版）》
EI
CAS
CSCD
2004年第1期57-60,共4页
Journal of Sichuan University (Engineering Science Edition)
