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How does carbon monoxide reduce lead oxides during smelting?

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Metallurgy — lead processing A zinc-lead blast furnace and lead-splash condenser. This technology is utilized mainly for producing zinc while managing both lead and zinc from raw materials, a technique that was highly influential in 20th-century smelting.

In the process of lead smelting, carbon monoxide acts as a chemical reducing agent to extract metallic lead from lead oxides.

Within a blast furnace, a charge consisting of lead oxide sinter and coke is heated. Air is blown into the lower part of the furnace, which facilitates the combustion of the coke. This combustion generates high temperatures and produces carbon monoxide gas.1

As this gas rises through the furnace, it reacts with the metallic oxides present in the sinter. During this chemical reaction, the carbon monoxide strips the oxygen from the lead oxides, resulting in the production of carbon dioxide and the release of molten metallic lead. This reduction process is essential for transforming the oxidized ore into the base bullion that is subsequently refined into commercial-quality lead.12