Open AccessResearches on the chemistry of coal. Part V.—The maturing of coal considered from the standpoint of its benzene-pressure-extraction
Publication year - 1928
Publication title -
proceedings of the royal society of london. series a, containing papers of a mathematical and physical character
Language(s) - English
Resource type - Journals
eISSN - 2053-9150
pISSN - 0950-1207
DOI - 10.1098/rspa.1928.0164
Subject(s) - fraction (chemistry) , benzene , chemistry , extraction (chemistry) , coal , softening point , alcohol , bituminous coal , petroleum , mass fraction , organic chemistry , chromatography , polymer chemistry
In Part III of this series it was shown that on extraction with benzene under “soxhlet” conditions, at pressures between about 18 and 48 atmospheres (corresponding with temperatures between 240° and 285° C.), the coal substance of some typical coking bituminous and non-coking sub-bituminous coals yielded between about 5 and 12 per cent, of its weight of an extract which, on treatment, successively, with light petroleum and ethyl alcohol, could be fractionated into four portions, as follows:— Concentrated Benzene Solution of Crude Extract ↓ Poured into Light Petroleum ↓ A B Soluble Insoluble ↓ ↓ Light Petroleum free from Benzene Ethyl Alcohol Soluble Insoluble Soluble Insoluble Fraction I Fraction II Fraction III Fraction IVFraction I consisted of neutral, yellowish-brown, non-nitrogenous, viscous oils or vaseline-like substances containing C = 83.3 to 89.7, H = 8.1 to 10.8, O = 2.3 to 5.5 per cent.Fraction II was a reddish-brown solid, softening about 25° C., and more difficult to characterise than the others.