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The effect of purification condition of a chromium terephthalate MIL-101 on gas storage (H2, CO2, and C2H2) and C2 hydrocarbon separations was investigated for MIL-101a, MIL-101b, and MIL-101c, which were obtained by three-step sequential purification using hot water/ethanol and aqueous NH4F solution treatments. MIL-101c was the best in terms of gas storage capacities among the three samples possibly due to the removal of free and coordinated terephthalic acids. Remarkably, MIL-101c exhibits among the highest total hydrogen uptake at 50 bar and 77 K (9.9 wt%) and shows considerably large deliverable capacity between 1.5 and 50 bar (7.6 wt%). Moreover, MIL-101c shows among the highest C2H2 storage capacity (6.4 mmol g−1) and deliverable capacity (4.3 mmol g−1) at 1 bar and 313 K. For C2H2/C2H6, C2H2/C2H4, and C2H4/C2H6 separations, MIL-101c exhibits higher adsorption capacities, working capacities and adsorption figure of merit (AFM) values while MIL-101b shows higher selectivities and sorbent selection parameters. These results clearly show that a proper purification of MIL-101 is important for gas storage and gas separations.

The hierarchically mesoporous iron(III) trimesate MIL-100(Fe) with a zeolite-MTN topology is known as an advanced functional material that is biocompatible. In this work, the large scale synthesis of MIL-100(Fe) has been achieved by hydrothermal reactions using suitable conditions without HF for the large scale synthesis. Although such conditions are narrow, the concurrent change of iron precursor and increase in the concentration of reaction mixture give rise to a synergetic effect leading to an increase in the crystallinity of F-free MIL-100(Fe). This method, combined with two purification steps (solvent extraction and chemical treatment with NH 4 F) leads to a highly porous F-free material obtained throughout a very high space–time-yield (>1700 kg/m 3 day). Possible formation mechanisms of MIL-100(Fe) under hydrothermal conditions have been proposed in terms of four steps such as hydrolysis, deprotonation, self-assembly, and polycondensation. The resulting material exhibits similar physicochemical properties to those of the one prepared in the presence of HF, except for a slight difference in sorption capacities of gases and liquid vapors corresponding to the difference of pore volume. Regardless of the use of HF, the purified MIL-100(Fe) possesses very high uptakes for both non-polar toluene and polar ethanol probe molecules due to the respective interactions with hydrophilic and hydrophobic sites in the framework. Finally, hydrophobicity measurements confirm that the dehydrated MIL-100(Fe) is more hydrophobic than conventional zeolite beta (SiO 2 /Al 2 O 3 = 25) and commercial iron trimesate (Basolite F300) from BASF SE.

A metal-organic framework HKUST-1 or Cu 3 (BTC) 2 was synthesized in mesopores of a COOH functionalized mesostructured cellular silica foam (MCF(M)-COOH), resulting in a hydrophobic nanocomposite. The Cu 3 (BTC) 2 formed in the MCF(M)-COOH has been prepared by a microwave method with sequential incorporation of copper nitrate and 1,3,5-benzenetricarboxylic acid in a water/ethanol mixture containing the MCF(M)-COOH. The nanocomposite was characterized by XRD, BET, FT-IR, TEM and solid state 13 C NMR. The nanocomposite had a higher hydrophobic property than pure Cu 3 (BTC) 2 and MCF(M)-COOH as a result of their hybridization. Moreover, the formation of the nanocomposite increased the sorption rate of cyclohexane vapor as compared with those of pure Cu 3 (BTC) 2 and MCF(M)-COOH due to the increased hydrophobicity.

In this work an iron MOF, MIL-100(Fe) is proposed as a plausible adsorbent to carry out C3/C4 separation by adsorption. The adsorption equilibrium of pure propane, propylene and isobutane over MIL-100(Fe) was studied by means of a magnetic suspension balance in a wide range of temperature and pressure (323–423 K and 0–500 kPa). Propane and propylene present nearly linear isotherms at high temperature, while isobutane present steeper isotherms at low pressures, showing higher adsorption capacity than that of propane and propylene in most of the studied range. Multicomponent fixed-bed adsorption experiments confirmed the preferential adsorption of isobutane over propane and propylene, with an adsorption separation factor of 3. A non-isothermal, non-adiabatic, bidisperse mass transfer model that describes satisfactorily the single and multicomponent breakthrough experiments is proposed.

Using a single, improved synthetic process, three different compounds comprising two known phases such as [Cu 3 (BTC) 2 (H 2 O) 3 ] ( 1 ), [Cu 2 (OH)(BTC)(H 2 O)] · 2 n H 2 O ( 2 ) and a new phase [Cu(BTC–H 2 ) 2 -(H 2 O) 2 ] · 3H 2 O ( 3 ) have been prepared by microwave-irradiation (MW) of identical reaction mixture of Cu(II) salt and trimesic acid, benzene-1,3,5-tricarboxylic acid (BTC–H 3 ) at different temperatures. The microwave synthesis of ( 1 ) has been compared to its conventional hydrothermal synthesis. It has been found that by using MW synthesis ( 1 ) can be obtained in a much shorter synthesis time with improved yield and physical properties. The effect of other synthetic parameters such as solvent, concentration of reactant mixtures and reaction time on the product ( 1 ) has been also studied. At high temperature, the compound ( 2 ) was obtained in the same solution. The new phase ( 3 ) has been characterized by elemental analysis, thermogravimetric analysis, IR spectroscopy, scanning electron microscopy and powder XRD analysis.