Patent · US Expired

Hydrometallurgical production of technical grade molybdic oxide from molybdenite concentrates

US3988418A · kind A · utility

7Cited by
1References
21Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 18, 1975
Grant dateOct 26, 1976
Priority date
Expiry dateAug 18, 1995

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY02P10/20
  • WIPO fieldMaterials, metallurgy
  • WIPO sectorChemistry

Abstract

An improved hydrometallurgical method is provided for producing technical grade molybdic oxide from molybdenite concentrates. According to this method, the molybdenite concentrates are leached in an acid medium having a nitric acid concentration between about 25 gpl and about 50 gpl and an initial sulphuric acid concentration of nil to about 750 gpl, under oxygen pressure of about 100 - 250 psig and at a temperature above 115.degree. C so as to produce technical grade molybdic oxide having not more than 0.1% sulphur. Then a liquid-solid separation of the reaction mixture is effected and the obtained leach liquor is recycled back to the leaching stage optionally after partial neutralization with a basic reagent. The solid is washed and recovered as technical grade molybdic oxide. This invention relates to a novel method of producing hydrometallurgically technical grade molybdic oxide from molybdenite concentrates. Technical molybdic oxide is usually prepared commercially by roasting molybdenum disulphide concentrates in air at temperatures of 550.degree.-600.degree. C. These molybdenum disulphide concentrates commonly contain minor amounts of silica and iron, copper and lead sulphid…

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.