From molecules to processes: Molecular simulations applied to the design of simulated moving bed for ethane/ethylene separation

Abstract

This paper presents results of a modelling study on the separation of ethane/ethylene mixture by selective adsorption on zeolite 13X in a simulated moving bed (SMB) unit. Propane and n-butane are evaluated as desorbent candidates. The study encompasses molecular simulation calculations for determination of adsorption parameters, whose results will then be used in a mathematical model for evaluating the performance of an SMB unit. This work is entirely done in silico, by using available force field parameters for the molecular simulations part and reliable mathematical models for the SMB part. Experimental data are solely used for comparison with the molecular simulation results, which are subsequently expanded to calculate adsorption properties for separating the mixtures, without further experimental work. The separation regions of an SMB unit operating with zeolite 13X for ethane/ethylene separation, using propane and n-butane as desorbents, were obtained by simulation at 110 kPa and at four different temperatures: 298, 323, 348 and 373 K. For each desorbent, an operating point was selected, and the size of the required unit was presented for the complete separation of the two components of the mixture.

Development of gas‐phase SMB technology for light olefin/paraffin separations

“…For the experiment with 0. 48 , meeting the industrial requirements for both components. The high desorbent consumption is due to the fact that the zone I flow rate was set to be high enough (with a safety margin) to ensure complete solid regeneration without further optimization.…”

“…48 Based on this previous work, propane was selected as desorbent for the considered ethane/ethylene separation.…”

“…48 The required adsorption equilibrium isotherms of ethane, ethylene, and propane on the binderless 13X zeolite beads were previously reported by our group. 20 Dynamic studies were performed to provide important information, not only for process modeling, but also for the SMB cyclic experiments.…”

Ethane/ethylene separation on a copper benzene-1,3,5-tricarboxylate MOF

“…A few studies based on some of the adsorbents mentioned above proved that it is feasible to produce ethylene from ethane/ethylene mixtures by PSA [13,40] and by SMB [41]. According to the study performed by Park and co-workers two different cycle schemes were suggested to obtain ethylene by VSA on AgNO3/clay adsorbent.…”

“…Granato et al developed a study, entirely performed in silico, and proved that it is viable to separate ethylene from ethane by SMB with a large productivity, using 13X zeolite as adsorbent and propane as desorbent [41]. numerically solved.…”