Reactions of a bituminous coal with metal chlorides in carbon tetrachloride

The interaction of a bituminous coal (87.2% C) with several metal chlorides in carbon tetrachloride was studied using the conditions under which graphite forms intercalation compounds. Adducts with SbCl₅, AlCl₃, FeCl₃ and MoCl₅ were isolated by filtration and washing with carbon tetrachloride. Atomic ratios versus coal carbon are as follows: C_10.0SbCl_7.4; C_6.2AlCl_4.1; C_6.3FeCl_3.3; and C_11.3MoCl_3.8. X-ray diffraction patterns of the adducts show no 002-band, the latter being partially recovered after extraction with diluted hydrochloric acid. The g-value of the e.s.r. signal of the coal vitrain shows a characteristic increase because of adduct formation with SbCl₅ and AlCl₃ and is reversible by hydrolysis extraction. The results obtained indicate that the bonding with SbCl₅ and AlCl₃ is mainly due to formation of chloro-complexes and with FeCl₃ and MoCl₅ — to formation of organo-metal complexes.