Functional group analysis in coal and on coal surfaces by NMR spectroscopy. Fossil energy quarterly report, October 1, 1989-December 31, 1989

摘要

An accurate knowledge of the oxygen-bearing labile hydrogen functional groups (e.g., carboxylic acids, phenols and alcohols) in coal is required for today's increasingly sophisticated coal cleaning and beneficiation processes. Phospholanes (compounds having the general structure -POCH(sub 2)CH(sub 2)O (1)) are being investigated as reagents for the tagging of liable hydrogen functional groups in coal materials with the NMR-active (sup 31)P nucleus. Of twelve such reagents investigated so far, 2 (2-chloro-1,3-dioxaphospholane, ClPOCH(sub 2)CH(sub 2)O) and 8 (2-chloro-1,3-dithiaphospholane, ClPSCH(sub 2)CH(sub 2)S) have been found to be useful in identifying and quantitating, by (sup 31)P NMR spectroscopy, labile hydrogen functional groups in an Illinois No. 6 coal condensate. Reagent 2 has also been used to quantitate moisture in pyridine extracts of Argonne Premium Coal Samples. Preliminary (sup 119)Sn NMR spectroscopic results on model compounds with the new reagent CF(sub 3)C(O)NHSnMe(sub 3) (N-trimethylstannyltrifluoroacetamide, 14) suggest that labile hydrogen functional groups in coal materials may be more precisely identified with 14 than with phospholanes. 14 refs., 2 figs., 2 tabs. (ERA citation 16:000071)