Rapid, Online Quantification of H_(2)S in JP-8 Fuel Reformate Using Near-Infrared Cavity-Enhanced Laser Absorption Spectroscopy

摘要

One of the key challenges in reforming military fuels for use with fuel cells is their high sulfur content, which can poison the fuel cell anodes. Sulfur-tolerant fuel reformers can convert this sulfur into H_(2)S and then use a desulfurizing bed to remove it prior to the fuel cell. In order to optimize and verify this desulfurization process, a gas-phase sulfur analyzer is required to measure H_(2)S at low concentrations (<1 ppm_(v)) in the presence of other reforming gases (e.g., 25-30percent H_(2), 10-15percent H_(2)O, 15percent CO, 5percent CO_(2), 35-40percent N_(2), and trace amounts of light hydrocarbons). In this work, we utilize near-infrared cavity-enhanced optical absorption spectroscopy (off-axis ICOS) to quantify H_(2)S in a JP-8 fuel reformer product stream. The sensor provides rapid (2 s), highly precise (+-0.1 ppm_(v)) measurements of H_(2)S in reformate gases over a wide dynamic range (0-1000 ppm_(v)) with a low detection limit (3sigma velence +-0.09 ppm_(v) in 1 s) and minimal cross-interferences from other present species. It simultaneously quantifies CO_(2) (+-0.2percent), CH_(4) (+-150 ppm_(v)), C_(2)H_(4) (+-30 ppm_(v)), and H_(2)O (+-300 ppm_(v)) in the reformed gas for a better characterization of the fuel reforming process. Other potential applications of this technology include measurement of coal syngas and H_(2)S in natural gas. By including additional near-infrared, distributive feedback diode lasers, the instrument can also be extended to other reformate species, including CO and H_(2).