Extractive metallurgy roasting

The reaction equations of the cycle using liquid Pb are shown in Table IV. As a means of preparing Pb from PbS, the roast-reaction or air-reduction method is well-known in nonferrous extractive metallurgy. The reactions for this method can be presented as follows ... 

In extractive metallurgy, for instance, certain low-grade copper ores could be leached with acid or ammoniacal solution advantageously in the fluidized state cupriferous iron ores, after sulfatizing roasting, could have their copper values recovered selectively by leaching with a very dilute acid (Yu et al., 1964) ... 

These sources are detailed in the book, but our main subject is production of sulfuric acid from S02(g). Readers interested in smelting and roasting offgases might enjoy our other books Extractive Metallurgy of Copper (2002) and Flash Smelting (2003). 

Extractive metallurgy refers to the process of extracting a metal from its ores. Generally this occurs in four steps. Concentration separates the ore from waste rock (gangue). Roasting converts the ore to the metal oxide. Reduction (usually with carbon) converts the oxide to the metal. Refining removes impurities from the metal. 

Pyrometallurgy. Metallurgy involved in winning and refining metals where heat is used, as in roasting and smelting. PyrometaHurgy is the oldest extractive process and is probably the most important. 

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