Bismuth compounds for medicine: Synthesis of bismuth (III) subgallate trihydrate

Bismuth (III) subgallate trihydrate C
₆
H
₂
(OH)
₃
COOBiOmiddot3H
₂
O was synthesized by precipitation from bismuth nitrate solutions by adding an aqueous solution of gallic acid as well as by the reaction of oxohydroxobismuth (III) nitrate trihydrate with a solution of gallic acid. The precipitates so produced were investigated by means of X-ray phase analysis, thermogravimetry, electron microscopy, IR spectroscopy and chemical analysis. It was shown that preliminary bismuth purification from metal impurities by its precipitation from nitrate solutions, as oxohydroxonitrate, is required for production of high purity bismuth (III) gallate trihydrate. Conditions for the production of the high purity product, its specific surface area and its composition were determined.