Thermodynamic Analysis of the Reduction of WO3 by Al Powder
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. The reduction of WO3 by Al powder is investigated thermodynamically. Simulations on the loss of Gibbs energy of these hypothetic reactions reveal that the reduction of WO3 and WO2(OH)2 (or H2WO4) is feasible when Al powder is used; and it is more difficult to generate the intermediate tungsten oxides such as WO2, WO2.72 and WO2.9. In addition, it is better to prepare tungsten powder in vacuum containers in view of economy.
Jimmy (C.M.) Kao, Wen-Pei Sung and Ran Chen
L. P. Chen et al., "Thermodynamic Analysis of the Reduction of WO3 by Al Powder", Advanced Materials Research, Vols. 581-582, pp. 616-619, 2012