Calcium sulfate dihydrate nucleation in the presence of calcium and sodiumchloride salts

Calcium sulfate dihydrate primary nucleation was experimentally studied in a batch crystallizer with a related optical device at a supersaturation ran ging from 2 to 4 and a fixed temperature T = 25 degreesC. The mother liquor was supersaturated with calcium sulfate in which calcium or sodium chlorid e salts were added to approach flue gas desulfurization stack-gas liquor. T he experimental results were compared with those obtained in the absence of foreign substances in solutions, showing that chloride salts influence gyp sum nucleation by increasing the induction period, thus retarding nucleatio n kinetics.