Abstract: A method of reducing sulfur-containing gases during conversion of a coal slab into metallurgical coke is disclosed. A sulfur-reducing agent is added to a coal slab, which may contain compacted coal aggregate. The coal slab, including the sulfur-reducing agent, is heated to produce metallurgical coke, which results in a reduced amount of sulfur-containing gases relative to an amount of sulfur-containing gases that would be produced by converting the coal slab into metallurgical coke without adding the sulfur-reducing agent to the coal slab before the coal slab is heated. The sulfur-reducing agent may be applied as a coating to the coal slab. The sulfur-reducing agent may include at least one of calcium carbonate, limestone, lime, magnesium carbonate, magnesium oxide, and the like.