Solvolytic extraction of coal through acylation and amidomethylation

Abstract Carboxylic acids, acid anhydrides and N-hydroxy methylamides were used to acylate Assam coal under Friedel—Crafts reaction conditions. This reaction resulted in the enhancement of the extractability of coal in benzene—methanol (7:3 vol./vol.) and quinoline after acylation with carboxylic acids and acid anhydrides. The effect of catalyst (AlCl 3 ) concentration on reaction was also investigated. l.r. spectra of reaction products indicated the introduction of acyl groups in the coal structure. Phthalimidomethylation could render about 50% coal extractable in quinoline.