NMR - Spektroskopie zur stofflichen Charakterisierung von Braunkohlen bei der hydrierenden Veredlung
By using a combination of modern analytical techniques including 1H-, 2H-NMR, 1C-CP-MAS-TOSS-NMR and GC/MS Coupling) with chemical/physical methods of converting and decomposing coal materials it is possible to draw conclusions about hydrogenation behaviour and structure. The results show that structure models developed for hard coals are not applicable to soft coals, which contain a relatively high proportion of oxygen-bearing groups and of water. Trials show that preheating brown coal to 75 and 100 C before hydrogenation leads to an increased oil yield at a relatively low hydrogenation temperature. The results of treatment with non-polar- and polar solvents differ widely from one another. After treatment for the removal of mineral, bitumen and humus by solvents, the coals react less well to hydrogenation, probably due to the removal of natural oil and water contents. Demineralization produces structural changes and the loss of iron with its autocatalytic effect on hydrogenation. Oxidation of soft brown coal with RuO4 revealed that the Eastern-Elbe coals possess lower levels of condensation than the Western-Elbe coals while investigations into Central-German coals reveal that they consist of single- and double-nucleus aromatics connected by methylene- and aliphatic ether bridges.
Bibliographic Reference: EUR 17431 DE (1998) 164pp.
Availability: Available from OOPEC Sales agents
ISBN: ISBN 92-828-5536-8
Record Number: 199910961 / Last updated on: 1999-07-16
Original language: de
Available languages: de