Preparation of calcium and magnesium hydrogen phosphates from natural dolomite and their sorptive properties

• Published in: Inorganic materials Vol. 36; no. 8; pp. 826 - 829
• Main Authors: SHASHKOVA, I. L, KITIKOVA, N. V, RAT'KO, A. I, D'YACHENKO, A. G
• Format: Journal Article
• Language: English
• Published: New York, NY Springer 01-08-2000; Springer Nature B.V
• Subjects: Adsorbents; Calcium phosphates; Chemical analysis; Chemistry; Dolomite; Exact sciences and technology; General and physical chemistry; Hydrogen; Magnesium phosphate; Phosphoric acid; Reaction products; Sorption; Surface physical chemistry; Magnesium Hydrogenphosphates; Phosphoric acid; Inorganic adsorbent; Calcium Hydrogenphosphates; Dolomite; Preparation
• ISSN: 0020-1685; 1608-3172
• DOI: 10.1007/BF02758605

The reaction of dolomite with 10–20% phosphoric acid was studied by x-ray diffraction and chemical analysis in a wide range of dolomite concentrations in the reaction system. The structure, composition, and sorption capacity of the reaction products were determined. The reaction was shown to yield a mixture of calcium hydrogen phosphate, CaHPO4 · 2H2O, with the brushite structure and magnesium hydrogen phosphate, MgHPO4 · 3H2O, with the newberyite structure. The sorption capacity of the reaction product for Pb ions was up to 19 mg-equiv/g. With 10% H3PO4 at an initial dolomite concentration of 0.17 g/ml, a near-theoretical reaction yield was attained.