The present invention provides a process for production of graphite coke from an admixture of coal and petroleum-based hydrocarbons. This particularly describes a process wherein a mixture of coal tar pitch and hydrocarbon feedstock such as CLO is purified in a solvent treatment step and the purified mixed feedstock is subjected to thermal cracking to produce high quality graphite/needle coke. This process also provides a synergy in improved coke quality coke formation while using an admixture of coal tar pitch and CLO while subjected to common purification and coking steps.

Implementations of the present disclosure relate to a method of operating a coker unit comprising the steps of: collecting a coker-furnace feed stream; introducing the coker-furnace feed-stream into a coker furnace for producing a coker-drum feed stream; and introducing a hydrogen-donor gas into either or both of the coker-furnace feed stream or the coker-drum feed stream.

Preparation methods of a high modulus carbon fiber (HMCF) and a precursor (mesophase pitch (MP)) thereof are provided. The preparation method of MP includes: separating components with a molecular weight distribution (MWD) of 400 to 1,000 from a heavy oil raw material through size-exclusion chromatography (SEC); subjecting the components to ion-exchange chromatography (IEC) to obtain modified feedstock oil, where, the components are passed through macroporous cation-exchange and anion-exchange resins in sequence to remove acidic and alkaline components; and subjecting the modified feedstock oil to thermal polycondensation and carbonization to obtain high-quality MP with prominent spinnability. With high mesophase content, low softening point, low viscosity, and prominent meltability and spinnability, the obtained MP is a high-quality raw material for preparing HMCFs. The obtained MP can be subjected to melt spinning, pre-oxidation, carbonization, and graphitization to obtain an MP-based HMCF.

A composite catalyst for coal depolymerization, the catalyst includes an agent A and an agent B. The agent A includes an iron salt-based catalyst, and the agent B includes a metal salt-based catalyst different from the iron salt-based catalyst. The agent A and the agent B are alternately added during use.

A delayed coking process for producing high grade coke comprising: introducing a hydrocarbon feedstock comprising asphaltenes to at least one fractionator to produce at least a bottoms fraction, an intermediate fraction and a light naphtha fraction: passing the bottoms fraction to a delayed coker unit furnace for heating to a predetermined coking temperature; passing the heated bottoms fraction to a first delayed coker unit to produce a first coke product and a first effluent substantially free of asphaltenes and comprising resins; and passing the first effluent to a second delayed coker unit to produce a second coke product comprising the high grade coke.

Systems and methods are provided for controlling the morphology of coke produced during delayed coking. The morphology control is achieved in part by introducing elemental sulfur into the coker feedstock prior to coking. The elemental sulfur can be introduced into the feed under conditions so that the sulfur is well-dispersed within the feed for a sufficient period of time. This can allow for relatively even reaction of sulfur with components throughout the feed, resulting in a relatively small, uniform domain size distribution for the coke produced during delayed coking. This coke can correspond to shot coke. By producing coke with a small and relatively uniform domain size distribution, the risk of uneven heating within the coke can be reduced or minimized.

A coking system comprises the 1st to the m-th heating units and the 1st to the n-th coke towers, each of the m heating units being in communication with the n coke towers, respectively, each of the n coke towers being in communication with one or more separation towers, respectively, in communication with the m-th heating unit and optionally with the i-th heating unit. The coking system can at least utilize petroleum series or coal series raw materials to produce high-quality needle coke with stable performance.

A process for the treatment of a hydrocracking unit bottoms stream containing heavy poly-nuclear aromatic (HPNA) compounds and/or a fresh hydrocracking feedstock stream containing HPNA precursors to produce coke. The HPNA and/or HPNA precursors are removed from the hydrocracking unit bottoms stream and/or a fresh hydrocracking feedstock stream by solvent washing, and the HPNA and/or HPNA precursors are subjected to delayed coking for the production of coke.

Hydrocracker bottoms fractions are treated to remove HPNA compounds and/or HPNA precursor compounds and produce a reduced-HPNA stream effective for recycle, in a configuration of a single-stage hydrocracking reactor, series-flow once through hydrocracking operation, or two-stage hydrocracking operation. The hydrocracker bottoms fractions are subjected to thermal cracking and HPNA compounds are removed with the coke phase.

Process embodiments for producing high grade coke and fuel grade coke from residual oil comprises: introducing the residual oil and a first paraffinic solvent having a carbon number C.sub.n to a first solvent deasphalting unit to produce a high quality deasphalted oil (HQDAO) fraction and a first asphalt fraction; passing the HQDAO fraction to a delayed coker to produce green coke; passing at least a portion of the first asphalt fraction and a second paraffinic solvent carbon number of C.sub.n+1 to a second solvent deasphalting unit to produce a low quality deasphalted oil (LQDAO) fraction and a second asphalt fraction; and passing the LQDAO fraction to the delayed coker to produce the fuel grade coke.