Separations of Non-Volatile Components in Fossil Fuels, at Very High Resolution, and Their Structural Characterization. Progress Report, April 1-December 31, 1983

摘要

The primary objective of the on-going research has been to find effective separation techniques for non-volatile complex mixtures derived from fossil fuel materials. Much progress has been achieved in the area of high-efficiency column technology since the beginning of the contract period when our microcolumns were still in their infancy. During the two-year period, the performance of our microcolumns has increased dramatically from the level shown in the supporting data for our first proposal: our current columns exhibit up to 250,000 theoretical plates and yield mixture separations corresponding to such efficiencies. While using reference fossil fuel samples, several previously described fractionation procedures had first to be tested for their suitability in the isolation and further fractionation of the non-volatile fuel fractions. A satisfactory procedure was adopted, but further clean-up steps had to be incorporated. Finally, sub-fractions were analyzed through high-efficiency micro-LC to yield adequate component resolution for two types of applications: (1) characterization and tentative compound identification in a model sample (solvent-refined coal, NBS SRC II); and (2) the development of highly resolved profiles for various substance classes for both technological and environmental purposes. Several types of materials were able to be screened, and various substance profiles were recorded and broadly characterized using mass spectrometry (MS). Low-resolution MS was used here as the primary means of compound characterization. The details of our research are discussed under the following four categories: development of suitable microcolumns; techniques of microcolumn chromatography; resolution of complex fossil fuel mixtures and characterization of their components; and fraction profiling. 2 figures. (ERA citation 10:012117)