Enrichment of W2B5 from WO3 and B2O3 by Double SHS Method

Abstract

A second self-propagating high-temperature synthesis (SHS) was carried out to enrich the W 2 B 5 content in the SHS product containing a mixture of various tungsten boride compounds. In the experiment, the process called Double-SHS (D-SHS) was conducted in two steps. In the first SHS reaction, an initial molar composition ratio of WO 3 :B 2 O 3 :Mg mixture was selected as 1:3:8. The product was then hot-leached with hydrochloric acid to eliminate MgO and Mg 3 B 2 O 6 phases. The leached product, consisting of 72.6 wt.% W 2 B 5 , 16.1 wt.% WB, 8.4 wt.% W 2 B, and 2.9 wt.% W, was again reacted with the Mg and B 2 O 3 mixture by second SHS. After another acid leaching step, W 2 B 5 content in the D-SHS product was found to be 98.2 wt.%. The study showed that D-SHS is an effective method for boron enrichment in the tungsten compounds. DOI: http://dx.doi.org/10.5755/j01.ms.24.1.17834