We propose a force field model for the description of water adsorption in Mg-MOF-74 and assess its accuracy by performing a series of molecular simulations. The model is defined in terms of electrostatic, repulsive, and attractive contributions, the parameters of which are independently derived from first-principles calculations. The force field accurately reproduces the most relevant part of the ab initio potential energy surface as well as pair-correlation functions obtained from molecular dynamics (MD) simulations. The model is further applied for calculating adsorption properties and isotherms within Monte Carlo and MD simulations. The obtained force field shows an improved description of the experimental adsorption isotherms compared to the standard water models, which allows us to expect its good performance for other large-scale simulations of water in Mg-MOF-74.

Self-diffusion coefficients for CO 2 , H 2 O, and mixtures thereof in Mg-MOF-74 have been determined using molecular simulations. The crystal structure was modeled in a rigid and flexible manner with the intent to identify the impact of the flexibility of the framework on the diffusivity. The results show that especially at low loadings the mobility of the molecules is enhanced in flexible lattices because of a small difference in adsorption energy and the enlarged equilibrium distance to the main adsorption sites. In mixtures the flexibility has the same influence; however, because of the presence of the secondary species, water is predominantly located in the close proximity of the magnesium-ion which effectively leads to a segregation effect from the more freely moving CO 2 .

Two zeolitic imidazolate frameworks, ZIF-9 and ZIF-71, are evaluated by adsorption experiments and molecular simulations with respect to their potential towards olefin/paraffin separation. Pure component adsorption isotherms are measured and compared to grand-canonical Monte-Carlo (GCMC) simulations. The experiments show that the adsorption of the paraffin is favorable over the olefin in both structures. Whereas [a]

Aqueous nonionic surfactant solutions split into two phases if the temperature is increased beyond a certain temperature, the so‐called cloud point temperature. Presently many different types of nonionic surfactants are produced commercially, out of these numerous have been considered as potential solvent for the cloud point extraction. In this work the crucial thermophysical properties of nonionic surfactants are investigated to determine the potential of surfactant systems for extraction processes. Phase equilibria of the binary system Triton X‐114/water and the ternary system Triton X‐114/water/phenol were measured. Based on these data the cloud point extraction was implemented in a continuous stirred extraction column. It was found, that increasing temperature within the column reduces the loss of surfactant and leads to an increasing enrichment factor. This work demonstrates that surfactant/water systems represent a suitable alternative to conventional solvents and can effectively be processed in continuous extraction columns.

Four metal-organic frameworks with similar topology but different chemical environment inside the pore structure, namely, IFP-1, IFP-3, IFP-5, and IFP-7, have been investigated with respect to the separation potential for olefin-paraffin mixtures as well as the influence of the different linkers on adsorption properties using experiments and Monte Carlo simulations. All IFP structures show a higher adsorption of ethane compared to ethene with the exception of IFP-7 which shows no selectivity in breakthrough experiments. For propane/propane separation, all adsorbents show a higher adsorption for the olefin. The experimental results agree quite well with the simulated values except for the IFP-7, which is presumably due to the flexibility of the structure. Moreover, the experimental and simulated isotherms were confirmed with breakthrough experiments that render IFP-1, IFP-3, and IFP-5 as suitable for the purification of ethene from ethane.