Method of producing molecular profiles of isoparaffins by low emitter current field ionization mass spectrometry

摘要

The present invention is devoted to an analytical method for directly determining carbon number and molecular weight distributions of isoparaffin mixtures. The analytical means uses low in-scan emitter-current field-ionization mass spectroscopy to substantially reduced or eliminated molecular ion fragmentation for isoparaffins, which allows direct measurement of isoparaffin molecular ions for their distributions. The analytical means is capable of directly characterizing isobutane to C₅₀+ isoparaffins, covering naphtha to gas oil ranges.