Navarro-Brull, Francisco J., Teixeira, Andrew R., Zhang, Jisong, Gómez, Roberto, Jensen, Klavs F. Reduction of Dispersion in Ultrasonically-Enhanced Micropacked Beds Industrial & Engineering Chemistry Research. 2018, 57(1): 122-128. doi:10.1021/acs.iecr.7b03876 URI: http://hdl.handle.net/10045/72578 DOI: 10.1021/acs.iecr.7b03876 ISSN: 0888-5885 (Print) Abstract: Channeling of gas can reduce mass transfer performance in multiphase micropacked-bed reactors. Viscous and capillary forces cause this undesired and often unpredictable phenomenon in systems with catalyst particle sizes of hundreds of micrometers. In this work, we acoustically modify flow in a micropacked-bed reactor to reduce gas channeling by applying high-power sonication at low ultrasonic frequencies (∼40 kHz). Experimental residence time distributions reveal two orders of magnitude reduction in dispersion with ultrasound, allowing for nearly plug-flow behavior at high flow rates in the bed. Sonication appears to partially fluidize the packed-bed under pressurized cocurrent two-phase flow, effectively improving dispersion characteristics. Keywords:Microreactor, Channeling, Capillary fingering, Ultrasound, Fluidization, Sonochemistry, Multiphase, Hydrodynamics American Chemical Society info:eu-repo/semantics/article