Collect. Czech. Chem. Commun. 1982, 47, 1-6

Existence of a new phase in barium carbonate-barium sulphate system

Bohumil Hájek, Jan Ondráček and Alexander Muck

Department of Inorganic Chemistry, Prague Institute of Chemical Technology, 166 28 Prague 6


The infrared spectroscopy, X-ray diffraction, TGA and DTA, and microscopic analysis techniques were applied to a study of BaCO3-BaSO4 systems, performed on samples prepared by precipitation from dilute aqueous solutions. A new BaCO3. 3 BaSO4 phase was established in the system with the BaSO4 structure exhibiting parallel extinction (replacement of the SO42- anion by a CO32- anion, the d values are equal). The BaCO3-BaCO3. 3 BaSO4 region contains a mixture of the two phases, the latter phase, however, may be oversaturated by carbonate. In the BaCO3. 3 BaSO4-BaSO4 region, unstable phases are formed with a lower content of carbonate.