premium coke

https://doi.org/10.1351/goldbook.P04814
An extremely well graphitizing carbon with a high degree of optical @AT06776@ (isochromatic areas of optical texture above about \(100\ \unicode[Times]{x3BC}\text{m}\)) and which is characterized by a combination of the following properties which differ significantly from those of @R05245@: high real density, low reversible thermal expansion and low ash content combined, in most cases, with low sulfur content.
Note:
Premium @C01142@ is mainly produced from tars or residues from petrochemistry by the @D01578@. Also, refined @C01121@ are used as precursors for premium @C01142@ production.
Source:
PAC, 1995, 67, 473. (Recommended terminology for the description of carbon as a solid (IUPAC Recommendations 1995)) on page 501 [Terms] [Paper]