Novel Carbon Detector for Calibration-Free Characterization of Complex Fuel Mixtures

Research of complex energy systems, such as biomass pyrolysis and petroleum refining, requires analysis of mixtures containing hundreds of carbonaceous products [1]. The current state of the art utilizes gas chromatography for separation of compounds and flame ionization detection (FID) for quantification of individual compounds [2]. For quantification of complex mixtures, compounds must be identified and calibrated individually, a time-consuming and expensive process. Here, we present the design of the Quantitative Carbon Detector (QCD), a fully-integrated microreactor capable of quantifying complex mixtures without the need for calibration [3]. The QCD converts all carbonaceous GC analytes to methane (> 99.9%) via catalytic combustion and subsequent methanation, yielding identical FID response factors for all compounds. The design of the QCD provides the capability to detect and quantify carbon monoxide and carbon dioxide, compounds that cannot be detected via conventional FID. The QCD is seamlessly integrated with current GC-FID systems, and microreactor geometry, flows, and catalysts are optimized to ensure complete conversion of all carbon-containing analytes to methane with negligible loss in peak resolution. Thermodynamic calculations are used to optimize operating condition for the QCD to ensure complete conversion to methane. Implementation of the QCD for analysis of complex fuel mixtures allows for faster and more accurate quantification of carbon-containing analytes, providing improved capability to increasingly complex energy and fuels applications.

[1] Mettler, M. S., Paulsen, A. D., Vlachos, D., and Dauenhauer, P. J., Catalysis Science & Technology, 2014, 4, 3822-3825

[2] Paulsen, A. D., Mettler, M. S., and Dauenhauer, P. J., Energy & Fuels, 2013, 27(4), 2126-2134

[3] Maduskar, S. et al., Lab on a Chip, 2015, 15, 440-447