发明授权
US4624844A Process for producing ammonium paratungstate 失效
生产仲钨酸铵的方法

Process for producing ammonium paratungstate
摘要:
A process is disclosed for producing ammonium paratungstate which involves adding hexamethylenetetramine to a first solution of ammonium tungstate, adjusting the pH to about 2 with an acid to form a precipitate which contains the major portion of the tungsten and the hexamethylenetetramine and separating the precipitate from the resulting mother liquor. The tungsten hexamethylenetetramine precipitate is then dissolved in aqueous ammonia to form a second ammonium tungstate solution which is then heated at from about 90.degree. C. to about 100.degree. C. to form a precipitate essentially all of which is ammonium paratungstate and a mother liquor which contains essentially all of the hexamethylenetetramine. The ammonium paratungstate precipitate is then separated from the mother liquor.
信息查询
0/0