Coking

Heating of coal in the absence of oxygen

Coking is the heating of coal in the absence of oxygen to a temperature above 600 °C (1,112 °F) to drive off the volatile components of the raw coal, leaving a hard, strong, porous material of high carbon content called coke. Coke is almost all carbon. The porosity gives it a high surface area, which makes it burn faster. When a kilogram of coke is burned it releases more heat than a kilogram of the original coal.

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