NIOBIUM POWDER AND A PROCESS FOR THE PRODUCTION OF NIOBIUM AND/OR TANTALUM POWDERS

文件类型：PDF文档
文件大小：703K
The process comprises the reduction of niobium and/or tantalum oxides by means of alkaline earth metals and/or rare earth metals, wherein the first reduction stage is carried out as far as an average composition corresponding to (Nb, Ta)O x where x = 0.5 to 1.5 and before the second stage the reduction product from the first stage is freed from alkaline earth oxides and/or rare earth metal oxides which are formed and from excess alkaline earth metal and/or rare earth metal by washing with mineral acids.