TY - JOUR
T1 - Simultaneous Measurement of In-Situ Bubble Size and Reaction Rates with Heterogeneous Catalytic Hydrogenation Reaction
AU - Hu, Binjie
AU - Fishwick, Robert
AU - Nienow, Alvin
AU - Pacek, Andrzej
AU - Winterbottom, John
AU - Wood, Joseph
AU - Stitt, EH
PY - 2007/9/1
Y1 - 2007/9/1
N2 - The effect of solvent composition (water, 2-propanol and mixtures of the two) on the three phase, heterogeneously catalysed, two-step hydrogenation of 2-butyne-1,4-diol on Pd/alumina was investigated in a stirred reactor and for the first time, bubble sizes were measured in situ simultaneously with reaction rates. The first step forming the alkene is slow and gas-liquid mass transfer limitation is unlikely whilst the second step to alkane is much faster and may be mass transfer dominated. Overall, reaction rates displayed a complex relationship with solvent composition. The smallest bubbles where observed with 5%v/v 2-propanol in water and under gas-liquid mass transfer limited conditions (energy dissipation rates <4 W/kg), the overall reaction closely follows the ratio of mean bubble diameter to hydrogen solubility, both of which are a function of solvent. Overall, the solvent 5%v/v 2-propanol/water gave faster reactions combined with pod selectivity compared to the others and is therefore recommended. (c) 2007 Elsevier Ltd. All rights reserved.
AB - The effect of solvent composition (water, 2-propanol and mixtures of the two) on the three phase, heterogeneously catalysed, two-step hydrogenation of 2-butyne-1,4-diol on Pd/alumina was investigated in a stirred reactor and for the first time, bubble sizes were measured in situ simultaneously with reaction rates. The first step forming the alkene is slow and gas-liquid mass transfer limitation is unlikely whilst the second step to alkane is much faster and may be mass transfer dominated. Overall, reaction rates displayed a complex relationship with solvent composition. The smallest bubbles where observed with 5%v/v 2-propanol in water and under gas-liquid mass transfer limited conditions (energy dissipation rates <4 W/kg), the overall reaction closely follows the ratio of mean bubble diameter to hydrogen solubility, both of which are a function of solvent. Overall, the solvent 5%v/v 2-propanol/water gave faster reactions combined with pod selectivity compared to the others and is therefore recommended. (c) 2007 Elsevier Ltd. All rights reserved.
KW - multiphase reactions
KW - catalysis
KW - reaction engineering
KW - stirred tank reactor
KW - mass transfer
U2 - 10.1016/j.ces.2007.01.004
DO - 10.1016/j.ces.2007.01.004
M3 - Article
SN - 1873-4405
VL - 62
SP - 5392
EP - 5396
JO - Chemical Engineering Science
JF - Chemical Engineering Science
IS - 18-20
ER -