TY - JOUR
T1 - Analysis of a carbon membrane reactor
T2 - From atomistic simulations of single-file diffusion to reactor design
AU - Sheintuch, Moshe
AU - Efremenko, Irena
N1 - Funding Information:
Work supported by the Israeli Ministry of Science and by the Ministry of the Immigrant Absorption.
PY - 2004/11
Y1 - 2004/11
N2 - We study the dehydrogenation of iso-butane in a membrane reactor with carbon membranes; these are molecular sieves with pores of molecular dimensions. To provide information on the transport laws of the various components, for reactor design purposes, we studied the separation in a membrane module either by maintaining the shell-side under lower pressure (or under vacuum) or by sweeping it with an inert diluent stream. The purpose of this work is to derive multi-component flux expressions for single-file diffusion in these two modes of separation, using molecular mechanics calculations of the thermodynamics of molecular adsorption into, diffusion within and desorption from the pores, and apply them for reactor design. In the process we calibrate these expressions with integral measurements of separation in a membrane module. Good predictions of reactor performance are obtained for a reaction coupled with separation by sweeping the hydrogen with nitrogen but poor predictions were achieved for a reaction coupled with vacuum-driven separation. Reactor performance in the former mode is better due to excellent transport selectivity, which we attribute to mutual blocking of counter-diffusion by nitrogen and hydrocarbons.
AB - We study the dehydrogenation of iso-butane in a membrane reactor with carbon membranes; these are molecular sieves with pores of molecular dimensions. To provide information on the transport laws of the various components, for reactor design purposes, we studied the separation in a membrane module either by maintaining the shell-side under lower pressure (or under vacuum) or by sweeping it with an inert diluent stream. The purpose of this work is to derive multi-component flux expressions for single-file diffusion in these two modes of separation, using molecular mechanics calculations of the thermodynamics of molecular adsorption into, diffusion within and desorption from the pores, and apply them for reactor design. In the process we calibrate these expressions with integral measurements of separation in a membrane module. Good predictions of reactor performance are obtained for a reaction coupled with separation by sweeping the hydrogen with nitrogen but poor predictions were achieved for a reaction coupled with vacuum-driven separation. Reactor performance in the former mode is better due to excellent transport selectivity, which we attribute to mutual blocking of counter-diffusion by nitrogen and hydrocarbons.
KW - Mass transfer
KW - Membranes
KW - Molecular mechanics
KW - Molecular sieves
KW - Reaction engineering
KW - Single-file diffusion
UR - http://www.scopus.com/inward/record.url?scp=9944261985&partnerID=8YFLogxK
U2 - 10.1016/j.ces.2004.09.016
DO - 10.1016/j.ces.2004.09.016
M3 - 文章
AN - SCOPUS:9944261985
SN - 0009-2509
VL - 59
SP - 4739
EP - 4746
JO - Chemical Engineering Science
JF - Chemical Engineering Science
IS - 22-23
ER -