著者
柿谷 悟 藤坂 正良
出版者
公益社団法人日本セラミックス協会
雑誌
窯業協會誌 (ISSN:18842127)
巻号頁・発行日
vol.66, no.750, pp.133-139, 1958-06-01
被引用文献数
3

In order to build up a background to the relative difficulty for burning the different raw materials in cement production the solid phase reactions between SiO<sub>2</sub> and either CaCO<sub>3</sub> or BaCO<sub>3</sub> at the temperatures ranging 500°-800°C were studied by measuring the amount of CO<sub>2</sub> liberated during the reaction. Then, applying the figures so obtained into the Jander's equation for solid phase reaction the authors have tried to work out the rate constants as well as the activation energies. However, it was found out that there were many examples which failed to fit in the equation, probably, due to the additional CO<sub>2</sub> liberated by simple thermal dissociation of the carbonates.<br>On the other hand, W. E. S. Turner et al. have suggested the acceleration of thermal dissociation of CaCO<sub>3</sub> when it was mixed with the powder of silica or of pure gold. The same trend was confirmed to exist also in the case of BaCO<sub>3</sub>.<br>Furthermore, the investigation of X-ray diffraction pattern has revealed that the reaction products of CaCO<sub>3</sub> and SiO<sub>2</sub> obtained by heating at 700°C in air for 242 hours was not wollastonite (βCaO⋅SiO<sub>2</sub>) but larnite (β2CaO⋅SiO<sub>2</sub>).