METHODS FOR PREPARING HIGH-PURITY MOLYBDENUM OR TUNGSTEN POWDER AND HIGH-PURITY OXIDES POWDER OF THE SAME

摘要

There are disclosed a method for preparing a high-purity molybdenum or tungsten powder comprising (a) decomposing a powder or an oxide powder of molybdenum or tungsten with hydrogen peroxide water; (b) bringing the resulting aqueous solution of molybdenum or tungsten into contact with a cation exchange resin; (c) concentrating the aqueous solution; and (d) reducing a concentrated solid material, and a method for preparing high-purity oxides powder thereof comprising (a) decomposing a powder or an oxide powder of molybdenum or tungsten with hydrogen peroxide water; (b) bringing the resulting aqueous solution of molybdenum or tungsten into contact with a cation exchange resin; and (c) concentrating the aqueous solution. …??The Mo and W powders and MoO3 and WO3 powders prepared by this invention are of an extremely high purity, and it thus is fair to say that they are useful as materials for targets of VLSI elements.