Hydrothermal preparation of tobermorite incorporating phosphate species

Slurries of quartz, slaked lime, and sodium dihydrogen phosphate containing hydrochloric acid as the solvent were hydrothermally treated to prepare tobermorite incorporating phosphate species. X-ray diffraction and X-ray fluorescence analyses showed that tobermorite with a trace of phosphate species formed after the treatment. The sizes of plate-like tobermorite depended on the sodium phosphate additive and solvent. There were almost no effects observed of the additive and solvent on the morphology of tobermorite. Sodium and/or phosphate species promoted the transformation from calcium silicate hydrate gel as the precursor to tobermorite. Phosphate species were introduced into the tobermorite structure, resulting in the distortion of its structure.