Title: coal tar pitch
Long Title: IUPAC Gold Book - coal tar pitch
DOI: 10.1351/goldbook.C01121
Status: current

Definition
A residue produced by distillation or heat treatment of coal tar. It is a solid at room temperature, consists of a complex mixture of numerous predominantly aromatic hydrocarbons and heterocyclics, and exhibits a broad softening range instead of a defined melting temperature.

Note
The hydrogen aromaticity in coal tar pitch (ratio of aromatic to total content of hydrogen atoms) varies from 0.7 to 0.9.

Related Terms
- aromaticity: https://goldbook.iupac.org//terms/view/A00442
- hydrocarbons: https://goldbook.iupac.org//terms/view/H02889
- melting: https://goldbook.iupac.org//terms/view/M03821
- pitch: https://goldbook.iupac.org//terms/view/P04677

Source
- PAC, 1995, 67, 473. 'Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)' on page 485 (https://doi.org/10.1351/pac199567030473)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/C01121/html
- json: https://goldbook.iupac.org/terms/view/C01121/json
- xml: https://goldbook.iupac.org/terms/view/C01121/xml

Citation: Citation: 'coal tar pitch' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.C01121
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Accessed: 2026-04-19T01:13:13+00:00