Production of Copper Molybdates by the Extraction-Pyrolytic Method

摘要

The dependence of the molybdenum recovery by isoamyl alcohol from solutions of ammonium paramolybdate on the HCl concentration is studied. Extracts with a metal content in the organic phase of up to 1.10 mol/dm3 are obtained. It is established by the method of infrared spectroscopy that Mo(IV) in an extractable compound gradually reduces to Mo(V) with the formation of aldehyde or acid. The molybdates CuMoO4 and Cu3Mo2O9 are synthesized by the pyrolysis of mixtures of molybdenum extracts in isoamyl alcohol and copper in n-octanoic acid. It is shown that the composition of the formed phases corresponds to the original stoichiometric ratios of metals in the mixture of extracts. The thermal decomposition of the mixture of Mo and Cu extracts proceeds in successive steps: before 350 ×C the CuCl and Cu phases are formed, which oxidize to Cu2OCl2 and CuO as the temperature rises. At over 350×C, there appear amorphous products of the destruction of the extractable Mo compound, and at the temperature range from 400 to 450 ×C the formation of molybdates takes place.