Method for dephosphorizing low-phosphorus ammonium tungstate solution

Abstract

The invention relates to a method for dephosphorizing a low-phosphorus ammonium tungstate solution. The method comprises the following steps of: adding phosphate into complicated black and white tungsten ore which cannot be dephosphorized by using calcium carbonate to perform low-alkali decomposition, directly performing the ion exchange process, dephosphorizing and transforming through ion exchange to obtain a solution of ammonium tungstate in which the concentration of residual phosphorus is 0 to 1g / L, adding anhydrous analytically pure magnesium sulfate into the solution of ammonium tungstate, and dephosphorizing to ensure that the phosphorus is transformed into an insoluble compound and is precipitated, tungsten still remains in the solution and other impurity elements are not introduced at the same time so as to fulfill the aim of separating the phosphorus and the tungsten. Process conditions are that: the using amount of the anhydrous analytically pure magnesium sulfate is 1.1 to 1.5 times the theoretical using amount; the pH value is 8 to 10; the reaction time is 1 hour; and the reaction temperature is normal temperature.

Description

technical field [0001] The invention relates to a method for dephosphorization of low-phosphorus ammonium tungstate solution, which is a smelting process for black and white tungsten mixed ore: "adding phosphate to low-alkali decomposition of black and white tungsten - calcium carbonate dephosphorization - ion exchange - ammonium tungstate solution to remove molybdenum - The innovation of "dephosphorization" technology in "preparation of APT by evaporation and crystallization", specifically, the low phosphorus (NH 4 ) 2 WO 4 The method of deep phosphorus removal is achieved by adding magnesium sulfate to the solution, so as to achieve the purpose of separating tungsten and phosphorus and producing high-purity APT. Background technique [0002] At present, some black and white tungsten mines are decomposed by adding phosphate and low alkali. In order to realize the separation of tungsten and phosphorus, the obtained sodium tungstate solution must be dephosphorized with calc...

AI Technical Summary

Problems solved by technology

During production, it was found that some complex black and white tungstenites were difficult to remove phosphorus with calcium carbonate after alkali decomposition

It mainly has the following problems: 1. The phosphorus cannot be removed by adding calcium carbonate for many times; Recycling of slag increases the production cost of enterprises

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