Abstract: A petroleum refinery residual oil derived from a naphthenic crude oil is catalytically demetalized, catalytically desulfurized and then fed to a delayed coker to produce premium delayed coke.

Abstract: A delayed coking process in which the overhead vapors from a delayed coking drum are separated into light hydrocarbon products and a gas oil, and in which the gas oil is hydrotreated after being separated from the light hydrocarbon products. The hydrotreated gas oil is then combined with coker feedstock and fed to the coking drum. The process produces a coke capable of producing a graphitized product having a lower longitudinal coefficient of thermal expansion than that of the coke product produced from the same feedstock by the same process but without the hydrotreating step.

Abstract: Characteristics of the feedstock for a delayed coking operation are determined prior to carrying out the coking operation, and the feedstock is adjusted by blending, thermal cracking, or other processing to provide certain predetermined characteristics to the feedstock prior to conducting the coking operation. Feedstocks having desired predetermined characteristics produce a premium grade coke having very low coefficient of thermal expansion.

Abstract: Isotropic petroleum coke is produced by air blowing a petroleum residuum to produce a delayed coking feedstock having a particular softening point and then coking said air-blown residuum with or without diluent under delayed coking conditions.