Monolith loop reactor for hydrogenation of glucose

Scale-up of monolithic post-reactor for gas-phase processes

“…With the applied coating recipe approximately 9 wt.% of the catalyst was deposited on the monolith with the first dip-coating step. This value is in the same range to the values reported in the literature [5,24,25].…”

“…Another possible reason like partially dissolution of the first deposited catalytic layer is not likely due to the expected stability after calcination step. Furthermore the results from Turek et al [24,25] indicates that the kind of active material on the base powder has also a significant influence on the coating results. The reason for this lies in the different zeta potentials between catalyst slurry and carrier.…”

Catalytic Transformation of Biomass Derivatives to Value‐Added Chemicals and Fuels in Continuous Flow Microreactors

“…[297,300,301] The gas-liquid hydrogenation of glucose to sorbitol has been reported using a washcoated Ru catalyst over γ-Al 2 O 3 support in a monolithic loop microreactor (400 cells per square inch (cpsi), corresponding to an average channel diameter below 0.625 mm) operated under slug flow ( Figure 3D; Table 6, entry 1). [150] The reaction rate in the microreactor was 1.5-2 times faster than that in a stirred tank slurry reactor. External (gas-liquid) mass transfer limitations were observed in the slurry reactor, while internal (liquid-solid) mass transfer limitations were more prevalent in the microreactor since the gas-liquid slug flow generated in monolithic channels considerably enhanced the external mass transfer.…”

“…[150] The reaction rate in the microreactor was 1.5-2 times faster than that in a stirred tank slurry reactor. [150] The hydrogenation of a mixture of C 5 sugars (L-arabinose and D-galactose towards arabitol and galactitol, respectively) was performed in a microreactor (d C = 2.4 mm) packed with 0.5 wt% Ru/C catalysts subject to an upstream slug flow ( Figure 3F; Table 6, entry 2). Thus, monolithic catalysts with sufficiently thin catalyst layers (to overcome internal mass transfer limitations), combined with their enhanced gas-liquid mass transfer, might be a promising alternative to suspended powder catalysts for enhancing the overall reaction rate for the hydrogenation of glucose.…”

“…Due to the strong shear force generated by centrifugal forces in the CCCS, liquid-liquid mixing is enhanced considerably, accelerating reactions with fast kinetics that are limited by mass transfer. [134] Typically, microreactors have been used for single liquid phase and biphasic (gas-liquid or liquid-liquid) catalytic transformation of biomass derivatives to valuable products using homogeneous or heterogeneous catalysts (e. g., the (biphasic) synthesis of furans from sugars, [135][136][137][138][139][140][141][142][143][144] (aerobic) oxidation, [144][145][146][147][148][149] and hydrogenation of biomass derivatives [144,[150][151][152][153] ). [126] Another intensified reactor configuration for multiphase (gasliquid or liquid-liquid) catalytic biomass transformation is the spinning disc reactor, consisting of a rotating disc around which fluids are fed.…”