Investigation of kinetics of solid-phase synthesis of lithium orthosilicate

The kinetics of the interaction between lithium carbonate and silica with v arious degrees of dispersion was investigated by TG and DTA methods. It was found that the utilization of pyrogenic silica with a specific surface are a of about 300 m(2) g(-1) instead of aerosil with one of 175 m(2) g(-1) lea ds to an increase of the reaction rate between lithium carbonate and silica , which depends on the formation and growth of lithium orthosilicate crysta ls in the first stage, and is conditioned by the diffusion of lithium and o xygen ions through the lithium orthosilicate layer formed at temperatures a bove 800 K. This supposition is supported by the kinetic analysis results o btained with the use of the different models. The optimal regime of heating is recommended.