1e:T443,Abstract A simple technique is described for calculating the adsorption equilibria for components in a gaseous mixture, using only data for the pure‐component adsorption equilibria at the same temperature and on the same adsorbent. The proposed technique is based on the concept of an ideal adsorbed solution and, using classical surface thermodynamics, an expression analogous to Raoult's law is obtained. The essential idea of the calculation lies in the recognition that in an ideal solution the partial pressure of an adsorbed component is given by the product of its mole fraction in the adsorbed phase and the pressure which it would exert as a pure adsorbed component at the same temperature and spreading pressure as those of the mixture. Predicted isotherms give excellent agreement with experimental data for methane‐ethane and ethylene‐carbon dioxide on activated carbon and for carbon monoxide‐oxygen and propane‐propylene on silica gel. The simplicity of the calculation, which requires no data for the mixture, makes it especially useful for engineering applications.1f:T425,The energy costs associated with large-scale industrial separation of light hydrocarbons by cryogenic distillation could potentially be lowered through development of selective solid adsorbents that operate at higher temperatures. Here, the metal-organic framework Fe(2)(dobdc) (dobdc(4-) : 2,5-dioxido-1,4-benzenedicarboxylate) is demonstrated to exhibit excellent performance characteristics for separation of ethylene/ethane and propylene/propane mixtures at 318 kelvin. Breakthrough data obtained for these mixtures provide experimental validation of simulations, which in turn predict high selectivities and capacities of this material for the fractionation of methane/ethane/ethylene/acetylene mixtures, removal of acetylene impurities from ethylene, and membrane-based olefin/paraffin separations. Neutron powder diffraction data confirm a side-on coordination of acetylene, ethylene, and propylene at the iron(II) centers, while also providing solid-state structural characterization of the much weaker interactions of ethane and propane with the metal.20:T4ea,The separation of ethane from its corresponding ethylene is an important, challenging, and energy-intensive process in the chemical industry. Here we report a microporous metal-organic framework, iron(III) peroxide 2,5-dioxido-1,4-benzenedicarboxylate [Fe₂(O₂)(dobdc) (dobdc^4-: 2,5-dioxido-1,4-benzenedicarboxylate)], with iron (Fe)-peroxo sites for the preferential binding of ethane over ethylene and thus highly selective separation of C₂H₆/C₂H₄ Neutron powder diffraction studies and theoretical calculations demonstrate the key role of Fe-peroxo sites for the recognition of ethane. The high performance of Fe₂(O₂)(dobdc) for the ethane/ethylene separation has been validated by gas sorption isotherms, ideal adsorbed solution theory calculations, and simulated and experimental breakthrough curves. Through a fixed-bed column packed with this porous material, polymer-grade ethylene (99.99% pure) can be straightforwardly produced from ethane/ethylene mixtures during the first adsorption cycle, demonstrating the potential of Fe₂(O₂)(dobdc) for this important industrial separation with a low energy cost under ambient conditions.

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