Petroleum coke (often abbreviated petcoke) is a carbonaceous solid derived from oil refinerycoker units or other cracking processes. Other coke has traditionally been derived from coal. Marketable coke is coke that is relatively pure carbon and can be sold for use as fuel (ie fuel grade coke), or for the manufacture of dry cells, electrodes (ie anode grade coke). Needle coke, also called acicular coke, is a highly crystalline petroleum coke used in the production of electrodes for the steel and aluminum industries. Catalyst coke is coke that has deposited on the catalysts used in oil refining, such as those in a catalytic cracker. This coke is impure and is only used for fuel.
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A residue that is the final product of the condensation process in cracking. This product is reported as marketable coke or catalyst coke. The conversion factor is 5 barrels per short ton. (DOE3)(DOE5)