DESULFURIZATION AND DENITROGENATION OF SRC LIQUIDS BY TRANSITION-METALS ON SOLID SUPPORTS

Low-valent transition metal complexes, such as bis(1,5-cyclooctadiene)nickel and 1,5-cyclooctadiene (η3-cyclooctenyl)cobalt, can rupture carbon-sulphur bonds in aryl sulphides and in SRC liquids at temperatures below 100 °C and in the absence of hydrogen gas. The desulphurizing activity of such complexes is markedly enhanced by the presence of main group metal hydrides. Furthermore, combinations of transition metal salts, amines and metal hydrides can efficiently desulphurize SRC liquids at temperatures of 55-75 °C, either in a batch operation where the coal liquid is slurried with the reagents, or in a percolation mode where the coal liquid trickles through a bed of the reagents dispersed on a solid support of alumina or poly(4-vinylpyridine). In the latter procedure, as an unexpected bonus, the nitrogen content of the SRC liquid is also sharply reduced. Although the percolation process for heteroatom removal is not catalytic, preliminary work has suggested that such percolation columns can be regenerated. © 1985.