Hydrodynamics and mass transfer enhancement of gas–liquid flow in micropacked bed reactors: Effect of contact angle

Abstract

Pressure drop, residence time distribution, dispersive behavior, liquid holdup, and mass transfer performance of gas–liquid flow in micropacked bed reactors (μPBRs) with different contact angles (CA) of particles are studied. The value of pressure drop for three types of beads can be obtained: copper beads (CA = 88.1°) > stainless steel beads (CA = 70.2°) > glass beads (CA = 47.1°). The liquid axial dispersion coefficient is 1.58 × 10−6 to 1.07 × 10−5 m2/s for glass beads and copper beads, which is smaller than those of trickle bed reactors. The liquid holdup of 400 μm copper beads is larger than that of 400 μm glass beads. The ratio of effective interfacial area enhancement is evaluated up to 55% for big contact angle beads compared with the hydrophilic glass beads. In addition, correlations of pressure drop, liquid holdup, and effective interfacial area in μPBRs with different wettability beads are developed and predicted values are in agreement with the experimental data.

Local and global gas–liquid mass transfer in a micro‐packed bed reactor utilizing a noninvasive colorimetric technique

“…21 In addition, our group employed the hydrogenation of α-methylstyrene system in the μPBR with Pd catalysts to obtain the external mass transfer performance of gas-liquid-solid reaction. 22 Wang et al 23 evaluated the effect of particle wettability on gas-liquid effective interfacial area of the μPBR and revealed that large contact angle was helpful for enhancing mass transfer.…”

“…In the above-mentioned studies, all results were obtained and calculated by variation of reactor inlet and outlet gas/liquid concentrations, representing the average values of mass transfer performance in the whole μPBR. [17][18][19][20][21][22][23] Nevertheless, the local differences of gasliquid flow behavior existed because of the sophisticated inner status inside the μPBR, 24 which induced the heterogeneous mass transfer in temporal and spatial dimensions possibly. The study of local mass transfer performance contributed to improve all-around understanding and guide the reactor optimization.…”