Abstract: The reaction kinetics of forsterite synthesis was studied through solid-phase reaction by using analytically pure magnesium oxide， high purity fused silica and fused magnesia particles as main raw materials. The effects of the sintering temperature and holding time on the synthesis of forsterite were studied by X-ray diffraction analysis and scanning electron microscopy. The mechanism of reaction between MgO and SiO₂ was discussed. The reaction kinetics equations of the reaction process between MgO and SiO₂ in the range of 1100~1300℃ were established， and the apparent reaction activation energy was obtained according to the experimental results. The results showed that forsterite synthesis rate gradually increases with the synthesis temperature and holding time increasing. Forsterite and enstatite are formed during the initial stage of synthesis reaction， and the reaction process of MgO and SiO₂ is controlled by the Mg²⁺ diffusion. The apparent reaction activation energy is (220±20)kJ/mol.

Key words: forsterite, solid-phase reaction, kinetics, diffusion-controlled, reaction mechanism