Term: delayed coking process
https://doi.org/10.1351/goldbook.D01578

Definition:
A thermal process which increases the molecular aggregation or association in petroleum-based residues or coal tar pitches leading to extended mesophase domains. This is achieved by holding them at an elevated temperature (usually 750-765 K) over a period of time (12-36 h). It is performed in a coking drum and is designed to ultimately produce delayed coke. The feed is rapidly pre-heated in a tubular furnace to about 760 K.

Note: @N04095@ is the premium product of the delayed @C01144@ process. It is generally produced from highly aromatic residues from, for instance, the steam @C01387@ of gas oil. Its appearance and preferred orientation of the @G02683@ is a consequence of the evolved gaseous products percolating through the @M03849@ which must not have too high a @V06627@. A close control of temperature, time and feedstock is essential. Lower grades, for instance @I03353@ cokes, are used for @C00829@ applied, for example, in the production of aluminium.

Related Terms:
1) needle coke (http://doi.org/10.1351/goldbook.N04095).
2) graphene layers (http://doi.org/10.1351/goldbook.G02683).
3) carbon electrodes (http://doi.org/10.1351/goldbook.C00829).
4) coal tar pitches (http://doi.org/10.1351/goldbook.C01121).
5) delayed coke (http://doi.org/10.1351/goldbook.D01577).
6) coking (http://doi.org/10.1351/goldbook.C01144).
7) cracking (http://doi.org/10.1351/goldbook.C01387).
8) mesophase (http://doi.org/10.1351/goldbook.M03849).
9) viscosity (http://doi.org/10.1351/goldbook.V06627).
10) isotropic (http://doi.org/10.1351/goldbook.I03353).
11) association (http://doi.org/10.1351/goldbook.A00472).

Source: PAC, 1995, 67, 473. 'Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)' on page 486 (https://doi.org/10.1351/pac199567030473)

Citation: 'delayed coking process' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.D01578

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