The purpose of this investigation is to study the effects of various impurities which might be present in sea-water magnesia on the sintering and dead-burning properties.
The influence of CaO, SiO₂, Al₂O₃, Fe₂O₃ etc. additions on the sintering and dead-burning of magnesia has been investigated. The results obtained are shown as follows;
(1) The sintering of dead-burned magnesia is influenced greatly by molar ratio of CaO/SiO₂ and CaO/Fe₂O₃, (2) and the suggestion is made that the effect of additions in promoting the sintering of sea-water magnesia may be related to the chemical composition of the original sea-water magnesia.
(3) The relation between the sintering characteristics of magnesia and molar ratio CaO/SiO₂, CaO/Fe₂O₃, and CaO/Al₂O₃ was made clear.
(4) There is no obvious relationship between the densification of dead-burned magnesia and the promoting growth of periclase crystals.
(5) An optimum addition of additives beyond which sintering is inhibited was determined from the study of mineral composition of products.