ABSTRACT
Alkali fusion involves heating ores or concentrates with an alkali or alkaline earth reagent to render the mineral values in the raw material amenable to further treatment. In most cases fusion takes place. The alkali fusion of bauxite for aluminum recovery was used before Bayer's invention of the pressure leaching method. Beryl can be decomposed by heating at about 1000°C with Na2CO3, or a mixture of Na2CO3 and CaO, or by heating at 300°—400°C with NaOH. There are a number of methods used for extracting vanadium from carnotite ores. In one of these methods now absolete, the ore was sintered with Na2CO3 whereby both vanadium and uranium were converted into water-soluble compounds. The ore was smelted in a conventional way to white metal analyzing approximately: 48% Ni, 27% Cu, 2% Fe, and 23% S. This was then mixed with sodium sulfide and the mixture fused, then allowed to cool whereby the two layers separate.
