Advanced solids NMR studies of coal structure and chemistry. Progress Report211 including the Period September 1, 1996 to March 1, 1997

摘要

This report covers the progress made on the title project for the project period.211u001eThe study of coal chemical structure is a vital component of research efforts to 211u001edevelop better chemical utilization of coals, and for furthering our basic 211u001eunderstanding of coal geochemistry. In this grant we are addressing several 211u001estructural questions pertaining to coals with advances in state of the art solids 211u001eNMR methods. Our goals are twofold. First, we are interested in developing new 211u001emethods that will enable us to measure important structural parameters in whole 211u001ecoals not directly accessible by other techniques. In parallel with these efforts 211u001ewe will apply these NMR methods in a study of the chemical differences between 211u001egas-sourcing and oil-sourcing coals. The NMR methods work will specifically focus 211u001eon determination of the number and types of methylene groups, determination of 211u001ethe number and types of methane groups, identification of carbons adjacent to 211u001enitrogen and sites with exchangeable protons, and methods to more finely 211u001echaracterize the distribution of hydrogen in coals. The motivation for 211u001einvestigating these specific structural features of coals arises from their 211u001erelevance to the chemical reactivity of coals, and their suitability for possible 211u001ecorrelations with the oil sourcing potential of some types of coals. The coals to 211u001ebe studied and contrasted include oil-prone coals from Australia and Indonesia, 211u001ethose comprising the Argonne Premium Coal Sample bank, and other relevant 211u001esamples. In this report period we have focused our work on 1 segment of the 211u001eprogram. Our last report outlined progress in using our NMR editing methods with 211u001ehigher field operation where higher magic angle spinning rates are required. 211u001eSignificant difficulties were identified, and these have been the main subject of 211u001estudy during the most recent granting period.