Microwave-assisted combustion synthesis of molybdenum

Self-propagating high temperature synthesis (SHS) is one variety of combustion, in which, as a result of a fast reaction, the valuable condensed products are formed. Although the reactant in (SHS) may be in various states of solid, liquid or gas, the products after cooling should be in solid state. Molybdenite concentrate from Sarchechme mines (South-east of Iran) with the composition of mainly: 41.5% S, 2.8% Fe, 1.3% Cu and 47.7% Mo by weight was used as a source of molybdenum. It was mixed with different concentration of aluminum, pressed to a briquette of 25.4 mm. in diameter and ignited by use of a microwave oven. Depending on the conditions, different modes of combustion of the briquettes were observed. The product of the reaction was leached with dilute hydrocholoric acid, and was tested for sulfur, aluminum and molybdenum. The respective effects of aluminum powder size, pellet density and power input to the pellet before ignition on the final product were investigated in some samples the sulfur was reduced to less than 1%.