(542c) Compact, In-Line Fuel Sulfur Analyzer for Improved Management of Desulfurizers

Fuel cell technology has progressed to the point where fuel desulfurization and reforming have become limiting factors. Both solid-oxide and polymer-electrolyte-membrane fuel cells are poisoned by sulfur compounds in transportation fuels. Sulfur removal is particularly challenging for military fuel cell applications because JP-8 jet fuel contains up to 3,000 ppm of sulfur, 200 times the highway diesel limit. In order to more efficiently manage desulfurization processes, improved in-line methods of determining the extent of sulfur contamination in fuel are required. We are developing a compact, in-line analyzer for measuring total sulfur in jet fuel for fuel cell applications. This analyzer is intended to allow less frequent desulfurizer regeneration events, compared to scheduling regenerations based on the assumed worst-case sulfur limit. The measurement technique employs multivariate analysis of infrared absorption spectra, which provides a robust calibration, outlier detection, and identification of fuel type. The sampling system is non-destructive and allows measurement of sulfur directly in the liquid fuel. Laboratory flow experiments with sulfur adsorbent columns are being performed to evaluate the end use of the sulfur analyzer. Several candidate desulfurizer control strategies that leverage the continuous measurement of fuel sulfur concentration are under evaluation. Sulfur analyzer development and testing as part of a desulfurizer control strategy will be presented.