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Zeolites and metal‐organic frameworks (MOFs) are considered as “competitors” for new separation processes. The production of high‐quality gasoline is currently achieved through the total isomerization process that separates pentane and hexane isomers while not reaching the ultimate goal of a research octane number (RON) higher than 92. This work demonstrates how a synergistic action of the zeolite 5A and the MIL‐160(Al) MOF leads to a novel adsorptive process for octane upgrading of gasoline through an efficient separation of isomers. This innovative mixed‐bed adsorbent strategy encompasses a thermodynamically driven separation of hexane isomers according to the degree of branching by MIL‐160(Al) coupled to a steric rejection of linear isomers by the molecular sieve zeolite 5A. Their adsorptive separation ability is further evaluated under real conditions by sorption breakthrough and continuous cyclic experiments with a mixed bed of shaped adsorbents. Remarkably, at the industrially relevant temperature of 423 K, an ideal sorption hierarchy of low RON over high RON alkanes is achieved, i.e., n ‐hexane ≫ n ‐pentane ≫ 2‐methylpentane > 3‐methylpentane ⋙ 2,3‐dimethylbutane > isopentane ≈ 2,2‐dimethylbutane, together with a productivity of 1.14 mol dm −3 and a high RON of 92, which is a leap‐forward compared with existing processes.

A series of isoreticular Zr carboxylate MOFs, MIL-140A, B and C, exhibiting 1D microporous triangular shaped channels and based on different aromatic dicarboxylate ligands (1,4-BDC, 2,6-NDC and 4,4’-BPDC, respectively), were...

hydrate equilibrium data for gas mixture of carbon dioxide and nitrogen in the presence of an emulsion of cyclopentane in water.. Journal of Chemical and Engineering Data, American Chemical Society, 2014, 59 (3) ABSTRACTCarbon dioxide and nitrogen gas separation is achieved through clathrate hydrate formation in the presence of cyclopentane. A phase diagram is presented in which the mole fraction of CO 2 in the gas phase is plotted against the mole fraction of CO 2 in the carbon dioxide + nitrogen + cyclopentane mixed hydrate phase, both defined with respect to total amount of CO 2 and N 2 in the respective phase. The curve is plotted for temperatures ranging from 283.5 K to 287.5 K and pressures from 0.76 MPa to 2.23 MPa. The results show that the carbon dioxide selectivity is moderately enhanced when cyclopentane is present in the mixed hydrate phase. Carbon dioxide could be enriched in the hydrate phase by attaining a mole fraction of up to 0.937 when the corresponding mole fraction in the gas mixture amounts to 0.507. When compared to the three phase hydrate-aqueous liquid-vapour equilibrium in the ternary system 2 {water +carbon dioxide + nitrogen}, the equilibrium pressure of the mixed hydrate is reduced by 0.95 up to 0.97. The gas storage capacity approaches 40 m 3 gas.m -3 of hydrate. This value turns out to be roughly constant and independent of the gas composition and the operating conditions.