물유리를 이용한 고순도 나노실리카 제조

Abstract

Silica nano-powder (SNP) is an inorganic material able to provide high-performance in various fields because ofits multiple functions. Methods used to synthesize high purity SNP, include crushing silica minerals, vapor reaction of silicachloride, and a sol-gel process using TEOS and sodium silicate solution. The sol-gel process is the cheapest method forsynthesis of SNP, and was used in this study. First, we investigated the shape and the size of the silica-powder particles inrelation to the variation of HCl and sodium silicate concentrations. After drying, the shape of nano-silica powder differed inrelation to variations in the HCl concentration. As the pH of the solution increased, so did the density of crosslinking. Initially,there was NaCl in the SNP. To increase its purity, we adopted a washing process that included centrifugation and filtration. After washing, the last of the NaCl was removed using DI water, leaving only amorphous silica powder. The purity of nanosilicapowder synthesized using sodium silicate was over 99.6%.