Effects of R2CO3 (RÂ =Â Li, Na and K) on the reduction of MoO2 to Mo by hydrogen

In the present work, the influence of different factors (additives and temperatures) on the morphologies and sizes of as-prepared metal Mo powders by the hydrogen reduction of MoO2 in the temperature range of 1053 K to 1353 K are investigated. When pure MoO2 powders are reduced, the morphologies and sizes of as-prepared metal Mo powders are nearly kept the same as the raw materials. However, it is found that adding a small amount of additives (Li2CO3, Na2CO3 and K2CO3) into MoO2 has a great influence on that of prepared metal Mo powders. The particles become uniformed, ultrafine and spherical powders. In addition, the particles size of the as-prepared metal Mo powders will become larger as the increase of reaction temperature due to the grains growth. This work provides a new method for the preparation of uniformed, ultrafine and spherical metal Mo powders.