METHOD OF PREPARATION OF RHODIUM NITRATE SOLUTION Russian patent published in 2005 - IPC

FIELD: chemistry of noble metals; preparation of rhodium nitrate solution.

SUBSTANCE: proposed method includes sintering of metallic rhodium with barium peroxide at temperature of 950-1050°C continued for at least 12 h. Ratio of metallic rhodium to barium peroxide is equal to 1:3.5. After sintering, leaching-out of sintered mass is performed by 25-% solution of nitric acid at temperature of 70-80°C. Pulp is filtered for obtaining insoluble sediment containing barium nitrate and rhodium oxides and nitric acid solution of rhodium nitrate. Barium nitrate is removed from solution by precipitation with the aid of sulfuric acid. It is filtered and finished solution of rhodium nitrate is obtained. Sediment containing rhodium oxides and barium nitrate is washed with water to remove barium nitrate and to obtain sediment of rhodium oxides and barium nitrate solution. Solution is concentrated for obtaining crystal barium nitrate followed by thermal decomposition to barium oxide and is directed for obtaining barium peroxide.

EFFECT: increased yield of target product; facilitated procedure.

5 cl, 1 dwg, 1 tbl