1. Ammonium molybdate nitrate neutralization method will be molybdenite crushed to 60 ~ 80 mesh, in the roaster at 500 ~ 550 for oxidation roasting 6 ~ 8h, leaching with ammonia, to get ammonium molybdate solution, purification and removal of impurities, with nitric acid acid acidification, precipitation of molybdic acid precipitation precipitate precipitation, washed with warm water, centrifugal dewatering, drying, crushing, to get molybdic acid finished products.
2. The hydrochloric acid solution of molybdenum trioxide MoO3 is heated at 40-60C to obtain molybdic acid H2MoO4. In addition, adding concentrated nitric acid to an aqueous solution of ammonium heptamolybdate tetrahydrate (ammonium secamolybdate) (NH4)6Mo7O24-4H2O, a monohydrate is obtained.
3. Molybdenum can be dissolved in AgNO3 solution, precipitating molybdic acid and silver, and the reaction can be carried out quantitatively.
4. The content of about 15% of ammonium molybdate solution added to the same volume of nitric acid solution (relative density of 1.16), then add a certain amount of ammonium nitrate and a small amount of molybdic acid crystals (as the crystal species), stirred well, and then stood until the crystallization of the complete: filtration of the resulting precipitate washed with iced water until qualified, filtering and drying, that is, anhydrous molybdic acid.
5. Add concentrated HNO3 to the aqueous solution of ammonium sec-molybdate to make the solution pH less than 1, or use barium sec-molybdate plus sulfuric acid and get.
