Two-stage reduction and reductive alkylation of coal using deuterium-labelled modifying agents

Coal conversion caused by a two-stage reduction or alkylation in the potass ium/liquid ammonia system was studied. The modifying agents were: C2H5OD an d CD3I for the reduction and alkylation, respectively. Analogous processes were also performed by the conventional method. It was found that the reduc tion and reductive alkylation of coal with the use of deuterium-labelled mo difying agents provided more information about these processes and about th e coal structure than when performed with the conventional method. The kind of hydrogen isotope had no effect on the coal transformation to products s oluble in dichloromethane. The two-stage reduction and alkylation resulted in an increase of the number of substituents introduced into coal compared with that introduced in the one-stage process. It has been observed that du ring the reduction and reductive alkylation, apart from certain substituent s originating from the modifying agent, also considerable amounts of ammoni a-originated hydrogen were introduced into the coal structure. (C) 2001 Els evier Science Ltd. All rights reserved.