Platelet Millireactor Filled with Open Cell Foam-Supported Pt Nanoparticles for a Three-Phase Catalytic System

• Published in: Industrial & engineering chemistry research Vol. 58; no. 22; pp. 9352 - 9361
• Main Authors: Nguyen, Thanh-Son, Swesi, Yousef, Edouard, David, Fongarland, Pascal
• Format: Journal Article
• Language: English
• Published: American Chemical Society 05-06-2019
• ISSN: 0888-5885; 1520-5045
• DOI: 10.1021/acs.iecr.9b01438

Platelet millimetric reactors (PMR, 18 mm × 5 mm × 24 or 120 mm) packed with open cell foam supporting Pt nanoparticles have been studied with a model reaction (formic acid oxidation). The hydrodynamics of the liquid phase was investigated as a function of gas and liquid superficial velocities and foam properties using classical residence time distribution (RTD) experiments. The gas–liquid mass transfer coefficient (k L a) was also studied by using an oxygen absorption in water for cocurrent up flow and down flow configurations with the velocities range of 1.1 < u g < 2.2 mm·s–1 for air and 0.075 < u l < 0.2 m·s–1 for liquid. It was found that an increase of gas velocity had no significant effect on gas–liquid mass transfer, contrary to an increase in liquid velocity. A correlation for k L a prediction was proposed based on a dimensionless numbers relation. A specific protocol was optimized to obtain an acceptable dispersion of Pt nanoparticles on SiC foam. Intrinsic catalytic activity was obtained in the chemical regime using a dedicated basket-type batch reactor adapted to solid foam in which the first-order kinetic constant was determined. Finally, experiments under a formic oxidation reaction with PMR have been performed. A simulation, based on the well-known axial-dispersion model for liquid phase and using hydrodynamic, mass transfer, and kinetic parameters determined in this work, was performed, and a good agreement was found with experiment without any parameters adjustments. The platelet configuration was also compared to a tubular configuration by simulation.