Recovery of refractory hard metal powder product

Abstract From the Canadian patent

Finely divided borides carbides, and nitrides of metals of, Groups III-VI of the Periodic Table formed by reacting vaporous metal, halide and a boron carbon, or nitrogen source reactant at high temperatures, e.g. 1500°C. are separated from gaseous reactor effluent streamat temperatures between about 200°C. and 1500°C. with the use of a porous sintered filter. By separating the finely divided product from the effluent stream before the stream cools to below about 200°C. adsorption of impurities, e.g. unreacted metal halide or metal subhalides on the, product is reduced. The use of a filter e.g. a porous sintered filter, avoids the size classification of product which may result when cyclones …