Effects of drying techniques on the crystal structure and morphology of ettringite

Abstract This study reports on the extent to which common drying methods, namely D-drying, oven-drying and vacuum-drying affect the structure and morphology of ettringite produced in the laboratory. In some cases, ettringite was washed with acetone, ethanol or isopropanol to remove excess water before drying. Results show that D-drying is the worst drying method in that it severely decomposes ettringite to form amorphous products of various composition, whereas vacuum-drying (either alone or used in combination with isopropanol washing) causes little damage to ettringite. Results also reveal that all organic solvents used in this study make ettringite samples susceptible to forming calcium carbonate.