TY - JOUR
T1 - the selective hydrogenation of butyne-1, 4-diol by supported palladiums: a comparative study on slurry, fixed bed, and monlith downflow dubble column reactors
AU - Marwan, H
AU - Winterbottom, John
PY - 2004/11/3
Y1 - 2004/11/3
N2 - The present study was carried out to asses performance of a Pd-monolith downflow bubble column (DBC) reactor, and compare it with that of the slurry and the fixed bed DBC. The selective hydrogenation of butyne-1,4-diol to cis-2-butene-1,4-diol over palladium catalyst was chosen as a model reaction. In principle, the monolith DBC allowed the reaction to take place under kinetic control regime. Comparison with DBC employing 5% Pd/C powder and 1% Pd-on-Raschig ring catalysts revealed a better performance of the monolith DBC (1% Pd loading) with advantage of smaller reaction volume and intensified reaction rate. In the monolith DBC, improved hydrogen transport was possible, as the interface between bubbles and the channel wall was very thin, thus, the length of the diffusion path was very short. In addition, the interfacial surface area at both gas-liquid and liquid-solid interface in the monolith was also very high. The reaction kinetics was well represented by the Langmuir-Hinshelwood mechanism. As an alternative to conventional three-phase reactors, the monolith DBC was simple due to its inherent characteristic operation and no specially designed device. (C) 2004 Elsevier B.V. All rights reserved.
AB - The present study was carried out to asses performance of a Pd-monolith downflow bubble column (DBC) reactor, and compare it with that of the slurry and the fixed bed DBC. The selective hydrogenation of butyne-1,4-diol to cis-2-butene-1,4-diol over palladium catalyst was chosen as a model reaction. In principle, the monolith DBC allowed the reaction to take place under kinetic control regime. Comparison with DBC employing 5% Pd/C powder and 1% Pd-on-Raschig ring catalysts revealed a better performance of the monolith DBC (1% Pd loading) with advantage of smaller reaction volume and intensified reaction rate. In the monolith DBC, improved hydrogen transport was possible, as the interface between bubbles and the channel wall was very thin, thus, the length of the diffusion path was very short. In addition, the interfacial surface area at both gas-liquid and liquid-solid interface in the monolith was also very high. The reaction kinetics was well represented by the Langmuir-Hinshelwood mechanism. As an alternative to conventional three-phase reactors, the monolith DBC was simple due to its inherent characteristic operation and no specially designed device. (C) 2004 Elsevier B.V. All rights reserved.
U2 - 10.1016/j.cattod.2004.07.003
DO - 10.1016/j.cattod.2004.07.003
M3 - Article
VL - 97
SP - 325
EP - 330
JO - Catalysis Today
JF - Catalysis Today
IS - 4
ER -