|About this Abstract
||2021 TMS Annual Meeting & Exhibition
||Rare Metal Extraction & Processing
||Preparation of High-grade Ammonium Metatungstate (AMT) as Precursor for Industrial Tungsten Catalyst
||Alafara Abdullahii Baba, Sadisu Girigisu, Mustapha A. Raji, Abdullah S. Ibrahim, Daud T. Olaoluwa, Kuranga I. Ayinla, Christianah O. Adeyemi, Aishat Y. Abdulkareem, Abdul G.F. Alabi, Mohammed J Abdul
|On-Site Speaker (Planned)
||Alafara Abdullahii Baba
The increasing demand for pure tungsten and its compounds considering their high tensile strength warrants their usefulness in catalyst, heavy alloy, cemented carbide, among others. This exceptional property also signals its interest by industrialists for use in the engineering and manufacturing sectors. Thus, preparation of AMT from a Nigerian wolframite ore by hydrometallurgical process was examined in sulphuric-cum-phosphoric acid solutions. During leaching, parameters such as leachant concentration, reaction temperature and particle size on ore dissolution were examined. At optimal conditions (2.0M H2SO4 + 0.15M H3PO4, 75°C, -63µm), 93.7% of the ore reacted within 120 minutes. The calculated activation energy of 6.93kJ/mol supported the proposed mechanism. The leachate at optimal conditions was analytically treated to obtain a pure tungstate solution. The purified solution was further beneficiated to produce a high grade AMT ((NH4)6[H2W12O40].4H2O : 96-901-3322, melting point: 98.7°C, density: 2.16g/cm3), which could serves as an intermediate material for some defined industries.