A performance evaluation of a microchannel reactor for the production of hydrogen from formic acid for electrochemical energy applications

An experimental evaluation of a microchannel reactor was completed to assess the reactor performance for the catalytic decomposition of vaporised formic acid (FA) for H₂ production. Initially, X-ray powder diffraction (XRD), elemental mapping using SEM-EDS and BET surface area measurements were done to characterise the commercial Au/Al₂O₃ catalyst. The reactor was evaluated using pure (99.99%) and diluted (50/50 vol.%) FA at reactor temperatures of 250-350°C and inlet vapour flow rates of 12-48 mL.min^-1. Satisfactory reactor performance was demonstrated at 350°C as near-equilibrium FA conversion (> 98%) was obtained for all flow rates investigated. The best operating point was identified as 350°C and 48 mL.min^-1 (pure FA feed) with a H₂ yield of 68.7%. At these conditions the reactor performed well in comparison to conventional systems, achieving a H₂ production rate of 11.8 NL.g_cat^-1.h^-1. This paper therefore highlights important considerations for ongoing design and development of microchannel reactors for the decomposition of FA for H₂ production.