低石炭化度炭における直鎖脂肪酸の存在形態

抄録

The original forms of straight-chain fatty acids in Taiheiyo coal and Joban lignite, and their carbon number distributions were investigated from the gas chromatograms of the extracts by pyridine and the saponification substances prepared by alkaliwater or alkali-methanol solution. Furthermore, the distributions of straight-chain alkanes derived by the hydrogenolysis using tetralin of the original coals and the residual coals obtained after the saponification were also discussed.
The origin of straight-chain alkanes produced in coal liquids was consequently elucidated from the original forms and the distributions of straight-chain fatty acids.
The original forms of straight-chain fatty acids in the coals could be distinguished clearly between free forms absorbed physically in the micropore structure and esterified form structures bonded within the bituminous or the humic substance. The predominance of odd carbon numbers over even was obserbed in the C₂₃ to C₂₉ straight-chain alkanes in the hydrogenolysis products of the original coals, and the C₂₂ to C₃₂ esterified fatty acids were present in the bituminous substance. Accordingly, it was estimated that a part of the odd carbon number alkanes was generated by scission in the positions adjacent to carbonyl groups in the esterified even carbon number fatty acids.