Screening metal–organic frameworks for separation of pentane isomers†
Abstract
This article compares the performances of several metal–organic frameworks (MOFs) and zeolitic imidazolate frameworks (ZIFs) for the separation of pentane isomers: n-pentane (nC5), 2-methylbutane (2MB), and 2,2-dimethylpropane (= neo-pentane (neo-P)) in fixed bed adsorbers. The required input data on unary and mixture adsorption equilibria are obtained from Configurational-Bias Monte Carlo (CBMC) simulations for twelve different adsorbents. The best separation performance is realized with Fe2(BDP)3, where BDP2− = 1,4-benzenedipyrazolate, a MOF with triangular shaped 4.9 Å channels that affords the ideal pore topology to differentiate between the three pentane isomers; the linear nC5 aligns commensurately with the pore landscape. Using transient breakthrough simulations in fixed bed adsorbers, the separation performance of Fe2(BDP)3 is found to be significantly superior to that of other materials.