The kinetic pathway of decomposition of MgSiO3 by alkali fusion using sodium hydroxide

摘要

The mechanism of decomposition of prepared MgSiO3 by alkali fusion using sodium hydroxide was studied by Raman spectroscopy in situ combining with X-ray diffraction analyses. The results show that alkali fusion MgSiO3 breaks down the bonds between bridging oxygen and silicon (Si-O-Si) within its chain structure. Therefore, the metasilicate with the chain structure is changed to the orthosilicate with the island structure during the fusion process. Sodium ions substitute for Mg ions in magnesium orthosilicate successively, and both Mg2SiO4 and Na2MgSiO4 are the reaction intermediates. The Na2SiO4 and Mg(OH)2 are obtained finally for the alkali fusion process.