Comparison of the liquefaction behaviour of a bituminous coal in two different batch autoclaves

• Published in: Fuel (Guildford) Vol. 68; no. 6; pp. 696 - 701
• Main Authors: Majchrowicz, Bernard B., Franco, Dirk V., Gelan, Jan M., de Vlieger, Jan J.
• Format: Journal Article
• Language: English
• Published: Oxford Elsevier Ltd 01.06.1989; Elsevier
• Subjects: Applied sciences; bituminous coal; Energy; Exact sciences and technology; Fuel processing. Carbochemistry and petrochemistry; Fuels; liquefaction; Solid fuel processing (coal, coke, brown coal, peat, wood, etc.); tetralin; liquefaction; bituminous coal; tetralin; Hydrogen transfer; Autoclave; Liquefaction; Conversion rate; Carbochemistry; Naphthalene(1,2,3,4-tetrahydro); Stirring; Bituminous coal
• ISSN: 0016-2361; 1873-7153
• DOI: 10.1016/0016-2361(89)90206-8

A Belgian coal was subjected to non-catalytic liquefaction with tetralin as a hydrogen donor solvent in a magnetically stirred 500 cm 3 autoclave (no. I) and a 70 cm 3 autoclave which was shaken horizontally (no. II). At 425 °C, coal conversion in both autoclaves increased when the tetralin/coal ratio was increased from 1 to 6, and was always smaller in autoclave no. II. At 400 °C, an improvement in conversion was no longer found in autoclave no. I for tetralin/coal ratios greater than 2, indicating the presence of sufficient hydrogen donor solvent. When the tetralin/coal ratio was decreased in either autoclave, increased aromaticity of the coal products was observed. Under similar conditions, both the conversion and the amount of hydrogen transferred from the solvent to the coal were lower in autoclave no. II than in no. I. The different results obtained were found to be due to the degree of filling of the autoclaves, and the mode of mixing. The latter also explains the presence in autoclave no. I of coal fragments with a relatively higher average molecular weight, and an increased formation of tetralin dimers.