Direct Synthesis of Molycarbide by Molybdenite-Carbon Monoxide Reaction in the Presence of Lime

Abstract

Studies have been conducted on the lime-scavenged reduction of molybdenite (MoS2) by carbon monoxide. The effects of quantity of CaO, CO gas flow rate, temperature and time have been investigated. Results indicate that lime can enhance MoS2 conversion by over 20 times and sulfur emission into off-gas can be as low as 12–15 ppm. These exploratory tests also show that it is feasible to achieve 99% reduction-conversion of MoS2 by its CO treatment in the presence of CaO (e.g. at 1273 K for 6.6 ks and 3.33 cm3 s−1 CO gas flow rate). After separating the unreacted CaO and CaS, the carbide product has been found to be of 98% purity. As compared to the traditional methods of producing molycarbide, this lime-scavenged CO reduction of MoS2 is suggested to be a simple and non-polluting route suitable for the direct synthesis of Mo2C.