| 摘要 |
<p>The parent patent claims a process for purifying solns. contg. alkali (bi)carbonates, sulphates or hydroxides as well as one or more of V, U and Mo, present as alkali salts and mineral and/or organic impurities, by (a) adding lime to the boiling soln. to convert (bi)carbonates to hydroxides; (b) sepg. and washing the resulting ppte. contg. CuCO3 and a mixt. of other (in)organic Ca salts; and (c) conc. of the soln. obtd., together with wash liquor, by evapn. to obtain a soln. of at least 50% alkali hydroxide concn. and a second ppte. which is then sepd. In the present invention, this second ppte., comprising a mixt. of alkali sulphate and molybdate is dissolved in an aq. liquor, the liquor is treated with an at least stoichiometric amt. of sulphide ions and acidified to a pH of less than 4.5 to ppte. Mo, the ppte. is sepd. from the resulting alkali sulphate soln. and water washed, the wash water is combined with the alkali sulphate soln., and the ppte. is dried to form a molybdenum sulphide cake. The process is used for purifying solns., which have been used for leaching Mo contg. U or V minerals, after sepn. of the metal values, to generate the alkali (bi)carbonate leaching soln. The second ppte. is treated, without causing environmental pollution, to give a valuable source of Mo and an alkali sulphate soln. suitable for recycling.</p> |
