Automated measurements of gas‐liquid mass transfer in micropacked bed reactors

Abstract

Gas-liquid mass transfer in micropacked bed reactors is characterized with an automated platform integrated with inline Fourier transform infrared spectroscopy. This setup enables screening of a multidimensional parameter space underlying absorption with chemical reaction. Volumetric gas-liquid mass-transfer coefficients (k L a) are determined for the model reaction of CO 2 absorption in a methyl diethanolamine/water solution. Parametric studies are conducted varying gas and liquid superficial velocities, packed bed dimensions and packing particle sizes. The results show that k L a values are in the range of 0.12$0.39 s 21 , which is about one-to-two orders of magnitude larger than those of conventional trickle beds. An empirical correlation predicts k L a in micropacked bed reactors in good agreement with experimental data.

Hydrodynamics and mass transfer of gas–liquid flow in micropacked bed reactors with metal foam packing

“…Zhang et al proposed a two‐phase hydrodynamic model incorporated capillary pressure effect into the Holub model and the model predicted the hydrodynamic data well for four types of glass beads (150–212, 250, 300–355, 355–425 μm). The gas–liquid mass‐transfer coefficients ( k L a ) is also found in the range of 0.12~0.39 s −1 in μPBRs, which is about 1–2 orders of magnitude larger than that of large‐scale TBRs. In general, the previous research showed the small dimension of particle packing in μPBRs generates a better mass transfer rate, and at the same time causes the gas–liquid phase maldistribution and results in high pressure drop and energy consumption.…”

“…The reactor was made of stainless steel with a length of 10 cm, the inner diameter of 3.87 mm, and the outer diameter of 6.35 mm (1/4 in.). More details about the reactor can be found in the literature . Each foam packing was cut into cylindrical shape by laser machine with a diameter of 3.87 mm and a height of 4 mm.…”

“…The photograph of real experimental setup has been given in Figure S2b. The chemisorption of 10% CO 2 into 0.2 mol/L MDEA solution has been proved to be suitable for gas–liquid mass transfer in μPBRs . MDEA solution was delivered by a metering pump at liquid superficial velocities of 1.42–7.79 mm/s and 10% CO 2 was feed by a thermal mass flow controller at gas superficial velocities of 21.25–106.27 mm/s.…”

“…CO 2 analyzer software was used to record CO 2 concentration of gas outlet in the separator. Using this data, the gas absorption rate and corresponding volumetric gas–liquid mass‐transfer coefficient ( k L a ) could be calculated following the methods described in the literature …”

Microfluidic synthesis of elastomeric microparticles: A case study in catalysis of palladium‐mediated cross‐coupling

“…Elastomeric microparticles loaded with a metal catalyst (Pd) are then loaded in a tubular Teflon reactor to construct a microparticle‐packed bed reactor (μ‐PBR) (Figure ). The μ‐PBR offers an increase in catalytic surface area and improved mass transport within the continuous flow reactor for biphasic C‐C cross‐coupling reactions while maintaining the Pd‐loaded elastomer's catalytic activity and the benefits of flow processes over batch methods …”