Removal of carbon dioxide is an essential step in many energy-related processes. Here we report a novel slurry concept that combines specific advantages of metal-organic frameworks, ion liquids, amines and membranes by suspending zeolitic imidazolate framework-8 in glycol-2-methylimidazole solution. We show that this approach may give a more efficient technology to capture carbon dioxide compared to conventional technologies. The carbon dioxide sorption capacity of our slurry reaches 1.25 mol l−1 at 1 bar and the selectivity of carbon dioxide/hydrogen, carbon dioxide/nitrogen and carbon dioxide/methane achieves 951, 394 and 144, respectively. We demonstrate that the slurry can efficiently remove carbon dioxide from gas mixtures at normal pressure/temperature through breakthrough experiments. Most importantly, the sorption enthalpy is only −29 kJ mol−1, indicating that significantly less energy is required for sorbent regeneration. In addition, from a technological point of view, unlike solid adsorbents slurries can flow and be pumped. This allows us to use a continuous separation process with heat integration.

The hydration properties of poly(N-isopropylacrylamide) in aqueous solution were investigated by Fourier transform infrared spectroscopy as a function of high hydrostatic pressure and compared to the thermally induced changes. We show that although both pressure and temperature induce a phase separation the underlying mechanisms are fundamentally different. It is well documented that increasing the temperature above the lower critical solution temperature causes a dehydration of the hydrophilic and hydrophobic moieties. By contrast, high pressure enhances the hydration of the hydrophilic amide group. Moreover, pressure strengthens the weak C−H···O hydrogen bonds between the hydrophobic alkyl groups and water, although a reorganization of the water network around the hydrophobic groups occurs during the phase separation. From this it is concluded that PNiPA remains in a coillike state at high pressure. In addition, we suggest that PNiPA is a good model for the study of the hydration properties of proteins.