The system 2CaO.SiO2-K2O.CaO.SiO2, and other phase-equilibrium studies involving potash

Abstract

This investigation is one of a series of studies undertaken for the purpose of determining the manner in which K20 is combined in portland cement clinker. The present research on the phase-equilibrium relations of 2CaO.Si02 and K20. CaO. Si02 was made after preliminary examinations had shown that the compound K20.AhOa was unstable in the presence of 3CaO.SiOz and 2CaO.Si02• The compounds 2CaO.SiOz and Kz.OCaO.SiOz were found to form a binary system containing one additional compound having a probable composition of K20. 23CaO.12SiOz. Thermal, optical, and X-ray diffraction data are presented and a temperature concentration diagram has been constructed.