Novel process for preparing tungsten powder by hydrogen reduction of tungsten trioxide

A novel process is proposed for the preparation of tungsten powder by the hydrogen reduction of tungsten trioxide. The process changes the traditional method of flow of hydrogen from the surface of WO3 followed by the slow diffusion of hydrogen to the WO3 to achieve reduction. Furthermore, a venting method from the bottom of WO3 was used, thus achieving enhanced reduction by hydrogen flow. The process promotes hydrogen contact with the WO3 and significantly reduces the partial pressure of H2O at the reaction interface, resulting in a higher reduction conversion than the traditional method under the same conditions. The average increase in the amplitude of the novel process is 45% when the conversions of the two processes are compared at temperatures between 750 °C and 950 °C. Besides, the tungsten powder produced by the novel process is finer and more uniform. Therefore, this process significantly improved the reduction efficiency and also has great potential in energy conservation and emission reduction.