A method for selective extraction and separation of molybdenum from high-phosphorus tungsten-molybdenum mixed solution

Abstract

The invention relates to a method of selectively extracting and separating molybdenum from a high-phosphorus tungsten- and molybdenum-containing mixed solution. In the prior art, according to the process of extraction and separation of tungsten and molybdenum through complexation of hydrogen peroxide, when the content of phosphorus in the solution is higher than 0.005 mol / L, the extraction efficiency of the tungsten and the molybdenum is greatly reduced, so that the conventional process of extraction and separation of the tungsten and the molybdenum through complexation of the hydrogen peroxide cannot be used for directly treating the tungsten- and molybdenum-containing mixed solution being higher than 0.005 mol / L in the content of the phosphorus. According to the invention, by means of adjustment and control of the content of acid in the high-phosprous mixed solution, the tungsten and the molybdenum in the mixed solution can be reacted with the phosphorus completely to form tungstomolybdophosphate acid. By means of addition of a proper amount of the hydrogen peroxide, the phosphor-tungstic heteropoly acid and phospho-molybdic heteropoly acid are depolymerized to generate peroxy phosphotungstic acid and peroxy phospho-molybdic acid. By means of TBP as an extraction agent, the peroxy phospho-molybdic acid is extracted into an organic phase and then the loaded organic phase is subjected to reverse-extraction by an alkaline reverse-extraction agent. The method can treat the high-phosphorus tungsten- and molybdenum-containing mixed solution, is low in co-extraction of tungsten, can reach 70% in molybdenum extraction rate in a single stage, is low in the cost of the employed extraction agent and is easy to industrialize.

Description

technical field

[0001] The invention belongs to the field of tungsten-molybdenum metallurgy, in particular to a method for selectively extracting and separating molybdenum from a high-phosphorus tungsten-molybdenum mixed solution. Background technique

[0002] Tungsten is an indispensable strategic metal in the field of national defense and occupies an important position in the national military strategic reserve. In view of the current situation of resources, it is an inevitable trend to replace black tungsten with scheelite, and it is a strategic choice for the sustainable development of my country's tungsten industry. However, my country's scheelite resource endowment is relatively poor, and there are many impurities such as molybdenum and phosphorus. Tungsten and molybdenum belong to the VIB group in the periodic table of elements. Due to the influence of lanthanide shrinkage, the properties of tungsten and molybdenum are very similar. The separation of molybdenum has b...

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