A combined experimental–computational study on the CO2 absorption on 1-butyl-3-methylimidazolium hexafluophosphate, 1-ethyl-3-methylimidazolium bis[trifluoromethylsulfonyl]imide, and 1-butyl-3- methylimidazolium bis[trifluoromethylsulfonyl]imide ionic liquids is reported. The reported results allowed to infer a detailed nanoscopic vision of the absorption phenomena as a function of pressure and temperature. Absorption isotherms were measured at 318 and 338 K for pressures up to 20 MPa for ultrapure samples using a state-of-the-art magnetic suspension densimeter, for which measure- ment procedures are developed. A remarkable swelling effect upon CO2 absorption was observed for pressures higher than 10 MPa, which was corrected using a method based on experimental volumet- ric data. The experimental data reported in this work are in good agreement with available literature isotherms. Soave–Redlich–Kwong and Peng–Robinson equations of state coupled with bi-parametric van der Waals mixing rule were used for successful correlations of experimental high pressure absorp- tion data. Molecular dynamics results allowed to infer structural, energetic and dynamic properties of the studied CO2 + ionic liquids mixed fluids, showing the relevant role of the strength of anion–cation interactions on fluid volumetric properties and CO2 absorption

Modifying sorbents for the purpose of improving carbon dioxide capture often results in the loss of surface area or accessible pores, or both. We report the first noninvasive functionalization of the polymers of intrinsic microporosity (PIMs) where inclusion of the amidoxime functionality in PIM-1 increases carbon dioxide capacity up to 17% and micropore surface area by 20% without losing its film forming ability.

Carbon dioxide (CO2) adsorption capacities of several Prussian blue (PB) analogues have been studied using the state-of-the-art Rubotherm® sorption apparatus to obtain adsorption and desorption isotherms of these compounds up to 50 bar. The analogues were prepared by simply reacting a [M(CN)6]3− (Mdouble bondCo, Fe) solution with solutions of M2+ (Mdouble bondMn, Fe, Co, Ni, Cu) metal ions. Characterization of the studied samples has been performed by using a combination of powder XRD, TGA, FTIR, and CHN elemental analysis. Adsorption capacities of PB analogues calculated with theoretical calculations, using Monte Carlo approach, have also been compared with the experimental study, and used to discuss the molecular mechanism of adsorption.

Nanoscale magnetite (Fe3O4) (<15 nm) is known to remove arsenic efficiently but is very difficult to separate or require high magnetic fields to separate out from the waste water after treatment. Anisotropic hexagonal ferrite (BaFe12O19, BHF) is a well-known permanent magnet (i.e., fridge magnets) and attractive due to its low cost in making large quantities. BHF offers a viable alternative to magnetite nanocrystals for arsenic removal since it features surfaces similar to iron oxides but with much enhanced magnetism. Herein, we employ BHF nanocrystalline materials for the first time in arsenic removal from wastewater. Our results show better (75 %) arsenic removal than magnetite of the similar sizes. The BHF nanoparticles, 6.06 ± 0.52 nm synthesized by thermolysis method at 320 °C do not show hexagonal phase, however, subsequent annealing at 750 °C produced pure hexagonal BHF in >200 nm assemblies. By using BHF, we demonstrate that nanoparticle removal is more efficient and fixed bed type cartridge applications are more possible.

We describe a facile protocol for the synthesis of PEGylated Au nanoparticles by simply mixing aqueous solutions of HAuCl4 and oligo(ethylene glycol) ethyl ether methacrylate. This method was applied to generate uniform multiply-twinned Au nanostructures of ∼21 nm in diameter with high yields. Our proposed mechanism indicates that the generation of primary alcohol intermediates from the nucleophilic addition reaction of water (nucleophile) with AuIII–vinyl complex is responsible for the reduction of gold ions. This protocol was also used to synthesize Ag nanoparticles and small aggregates of Pd nanoparticles. Due to the exclusion of sophisticated synthesis of PEG containing stabilizers, additional surfactants, or reducing agents, this approach provides a remarkably simple, versatile, and environmentally benign protocol to prepare PEGylated noble-metal nanocrystals. A comparative BSA adsorption study proved the lack of non-specific binding, a common obstacle in designing biocompatible nanoparticles.