Tungsten scheelite decomposition tungstic acid preparation is the traditional method in wet tungsten refractory. The tungstic acid obtained in this method often contains 0.2 ~ 3-2 impurity proportions that are mainly silica, h2sio3 molybdate, non-dissolved calcium tungstate and other minerals; before purification Materials absorbed from iron, aluminum, salt, phosphorus and arsenic compound, alkali metals and terrestrial metal alkali etc. What should not be directly used as raw materials can be used tungsten powder.
Tungsten Scheelite is a calcium tungstate ore and the main ingredient is calcium tungstate, along with often molybdene, fluorite (caf2), quartz, apatite, calcite (caco3), it can directly decompose with the manufacture of tungstic acid and other tungsten compounds. While tungsten is concentrated in tungsten manganese ore, a rigid solution of iron tungstate (fewo4) manganese tungstate (mnwo4). At the same time, it often comes together with tin (SnO2 molybdenite mos2), pyrite (fes2), (cufes2, chalcopyrite) ), Feldspar quartz (silica), (kalsi3o8 apatite), (ca) po4 (2) etc. Making it difficult for hydrolysis, and it often produces tungstic or non-tungsten acid after alkaline hydrolysis.