Thermodynamic Analysis of the Reduction of Na₂WO₄ through the Mechanochemical Reaction

Abstract:

Hydrogen is widely used to prepare tungsten from tungsten oxides. Such a gas is combustible and strict measures must be taken. However, assisted by Mg or Li₃N, tungsten can be prepared through the ball milling at room temperature. Al powder is supposed to be one of the proper reducers. Simulations on the loss of Gibbs energy of these reactions have been investigated. Studies reveal that the reduction of Na₂WO₄ is feasible when reducers such as Al, Mg and Li₃N are used; and the intermediate tungsten oxides such as WO₂, WO_2.72 and WO_2.9 can be seldom generated. In addition, the calculation favors that NH3 does not react with Na₂WO₄ or WO₃ theoretically.

• Periodical: Advanced Materials Research (Volumes 399-401)
• Pages: 85-89
• DOI: https://doi.org/10.4028/www.scientific.net/AMR.399-401.85
• Online since: November 2011
• Authors: Yuan Hong Gao, Jian Gao Yang, Bai Tao Su, Lian Ping Chen
• Keywords: Gibbs Energy, Li₃N, Reducer, Reduction, Tungsten

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