Abstract
In this study, the influence of calcium formate (CF) on the hydration of a synthesized calcium sulfate hemihydrate (HH) powder was investigated. Isothermal calorimetry measurements showed that CF retards the hydration reaction of HH. This was confirmed by XRD of stored samples and pore solution analysis. Two retardation mechanisms were identified. The combination of pore solution and laser granulometric experiments revealed that firstly, the initial dissolution of hemihydrate decelerates because of high Ca2+ ion concentrations, donated by the faster dissolving CF. Secondly, the HCOO− species of CF adsorb on surfaces of the gypsum crystals, as further pore solution measurements showed. This impedes their formation kinetic. The gypsum crystals exhibited anisotropic peak narrowing in XRD measurements when CF was added. This was caused by a morphology change, which could be verified using the anisotropic domain size morphology approach during Rietveld refinement analysis and SEM images. Gypsum crystals exhibit a blockier shape with CF addition compared to the usual acicular shape in pure water.
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
