Przemysl Chemiczny, Vol.91, No.5, 779-783, 2012
Effect of impurities on the conversion of calcium sulfate(VI) dihydrate to hemihydrate
CaSO4 center dot 2H(2)O was converted to CaSO4 center dot 0.5H(2)O in aq. soln. of H3PO4 (P2O5 content 24% by mass) at 90 degrees C for 2 h in presence of Fe3+, Al3+, Mg2+, F- and SiF62- ions to det. the conversion degree and habit of the crystals. The process was inhibited only in presence of F- and Al3+ ions at low F/AI ratio.