| 摘要 |
At least one basic precipitant selected from the group consisting of NaOH, KOH, NH<SUB>4</SUB>OH, NH<SUB>3</SUB>, NH<SUB>4</SUB>HCO<SUB>3 </SUB>and (NH<SUB>4</SUB>)<SUB>2</SUB>CO<SUB>3 </SUB>is added to an indium salt solution, which contains 0.1 to 3 M of indium, in an adding time of not longer than 24 hours, while the solution is maintained at a temperature of 5 to 95° C. until the equivalent of the basic precipitant reaches an equivalent of 0.5 to 3. Then, a precipitate obtained from the solution by a solid-liquid separation is dried and calcined at a temperature of 570 to 780° C. in an non-oxidizing atmosphere which contains ammonia gas and water vapor.
|
