On sulfatovanadatotungstates

The formation and composition have been studied of vanadatotungstates separated from the solutions with pH< 2. Hydrochloric, perchloric, and sulphuric acids have been tested for acidifying the mixed solution of vanadates and tungstates. Crystals of sodium and potassium vanadato tungstates Na2OxV2O5x8WO3xSO3x10H2O, 2K2OxV2O5x8WO3xSO3x9H2O have been separated from sulphate solutions with a ratio V:W = 1:3 by crystallization. The infrared spectra of the salts obtained have been recorded. The spectra are characterized by the absorption bands 480, 520,710, 780,840,940,1080,1165, and 1195 (cm-1). The compounds have been studied thermogravimetricaly and the PMR spectra have been recorded in the temperature range from - 130 deg to - 150 deg C. The separated sulphates of vanadatotungtates have been found to refer to a new type of heteropolycompounds