Four new magnesium 1,3,5-benzenetricarboxylate metal−organic framework materials (NICS-n; n = 3−6) were synthesized solvothermally in the presence of solvents with different EtOH/H 2 O ratios. We showed that the crystallization process of the Mg−1,3,5-benzentricarboxylate system strongly depends on the solvent composition, and that dimensionality of their structures can be tuned by changing the EtOH/water ratios in the reaction mixture. The presence of only water as a solvent yields the zero-dimensional molecular structure of Mg(structures were crystallized from EtOH/H 2 O mixtures with molar ratios of 0.3 and 0.4−0.7, respectively. The crystallization in pure ethanol yields Mg 3 (BTC) 2 material (NICS-6) with three-dimensional structure. Nuclear magnetic resonance investigations indicated that bulkier clusters of Mg species are formed in ethanol-rich solutions, even in the absence of the BTC ligand, and that the starting precursors formed with the reaction of Mg species and the BTC ligand at room temperature does not represent the final structures obtained by solvothermal reactions. NICS-4 and NICS-5 are formed from similar starting precursors but slightly different EtOH/H 2 O ratios causing the crystallization to go in two different directions. Systematic investigation of phase formation using different EtOH/H 2 O ratios, times, and temperatures of the synthesis along with the computational DFT studies confirmed that the 2D NICS-5 structure represents a thermodynamically more stable phase than 1D chainlike NICS-4. We showed that solvothermal reaction between Mg-precursors and the BTC ligand in EtOH/water mixture represents a complex and sensitive thermodynamic process.

The conventional distillation method to separate ethanol from water is energy-intensive and inefficient due to the presence of the azeotropic point of the binary system. Various processes have been proposed as potential separation techniques. Among them, preferential adsorptionbased separation is considered to be an efficient and energy-saving method for purification due to the easy regeneration under relatively mild conditions. In this work, the co-adsorption of gaseous water and ethanol on porous metal-organic framework (MIL-100(Fe)) in various 2 proportions has been studied by coupling FTIR spectroscopy with in-situ gravimetry (AGIR).The quantifications of co-adsorbed water and ethanol on the MIL-100(Fe) have been performed under different conditions (P/P0). Ethanol is preferentially adsorbed on MIL-100(Fe). Vaporliquid equilibrium of water/ethanol was altered when the pore volume of the MIL-100(Fe) was partially occupied. Our results suggest that the optimal conditions for the separation of H2O/EtOH on MIL-100(Fe) is at EtOH(P/Po)<0.05 with H2O(P/Po)<0.4 at room temperature.

A zinc trimesate Zn 2 (BTC)(OH)(H 2 O)•1,67H 2 O with the three-dimensional framework contains [Zn 2 O 6 (OH) 2 (H 2 O)] chains with the arrangement of ZnO 2 (OH) 2 tetrahedra and ZnO 4 (OH)(H 2 O) octahedra corner-shared through µ 3 -OH group. Inorganic chains are linked with 1,3,5-benzenetricarboxylates forming two types of parallel channels (open and closed) containing adsorbed water in different environments. Closed channels are occupied by free water molecules connected through strong hydrogen-bonds with coordinated water, whereas open-type channels contain water molecules with partially occupied oxygen atom sites. The dynamics of water adsorption/desorption was well evaluated by complementary techniques of TG, IR, water sorption and different MAS NMR techniques. The removal of water from open channels occurs below 100 o C, whereas hydrogen-bonded water molecules and coordinated water are expelled at higher temperatures. 2 H MAS NMR was employed to prove that the removal of water from closed channels is not entirely simultaneous and that adsorbed water begins to diffuse at slightly lower temperatures than the coordinated one. The investigated material shows high hydrothermal and withstands 40 cycle-hydrothermal stability tests without any significant loss of structure integrity. It also shows complete structural reversibility upon dehydration/rehydration process at 200 o C. The reason for high chemical resistivity to water mainly lies in the presence of the adsorbed water molecules interacting with the coordinated ones (framework water) by hydrogen bonds. The material also exhibits notable sorption capacity for water (208 mg•g -1 ) adsorbed in stepwise process.INTRODUCTION. The rational design of porous metal-organic frameworks (MOFs) aiming for the production of materials with the desired applicative properties is currently one of the most active research areas in the field of crystal engineering. [1][2][3][4][5][6][7][8] The development of MOFs is particularly focused for separation, catalysis and gas storage applications, due to their welldefined pore architectures, high surface areas, low framework densities and high concentration of active sites represented by free metal sites or organic functional groups.Great potential for the above mentioned applications that this group of materials offers is in large extent limited by their un-stability in humid conditions. 9-15 Knowledge of MOF performance under humid conditions is crucial before elevating these materials to the applied level. However, the parameters that contribute to the sensitivity to water are still relatively poorly understood. [16][17][18][19][20] It was already shown that pyrazolates and imidazolates in general exhibit higher chemical resistivity to water than carboxylate-based MOFs. Which is related to higher basicity (pK a ) of the nitrogen-based ligand and consequently stronger metal-ligand bonds in comparison with oxygen-based carboxylate ligands. 16,17,[20][21][22][23][24] Despite the fact that carboxylate-based MOFs tend to exhibit low...

So far, in situ-generated Ni nanoparticles have been reported to be efficient catalysts for tar cracking during wood liquefaction by pyrolysis. Herein, their performance in further bio-oil conversion steps is evaluated. Nanoparticles were generated for the first time from a Ni-containing metal-organic framework, MIL-77, during the hydrotreatment of glycerol-solvolyzed lignocellulosic (LC) biomass. Reactions were conducted at 300 °C and the H2 pressure was 8 MPa in a slurry reactor. The catalytic activity and selectivity of the deoxygenation and hydrocracking reactions for real biomass-derived feedstock using in situ-generated nanoparticles was compared with Ni nanoparticles dispersed on a silica-alumina support (commercial Ni/SiO2 -Al2 O3 catalyst). The mass activity of the in situ-generated nanoparticles for hydrogenolysis was more than ten times higher in comparison to their commercial analogues, and their potential for the use in LC biorefinery is discussed.

The new compound [Fe(H2cit)(H2O)]n (NICS-2) is the first neutral ferrous citrate carboxylate that has been synthesized up to now. The iron citrate coordination polymer was hydrothermally synthesized and the structure was solved using single-crystal X-ray diffraction. It crystallizes in an orthorhombic space group P2(1)2(1)2(1) (No. 19), with a = 5.9470 (4), b = 10.402(1) (5), c = 13.5773 (7) Å, V = 839.91 (8) Å(3), Z = 4. Its structure consists of one-dimensional chains of corner-sharing Fe(II)O6 octahedra that are additionally cross-linked with citrate ligands. Chains are additionally stabilized into a pseudo-three-dimensional structure by hydrogen bonds. The measurement of magnetic properties revealed that the magnetic moment is almost constant above 100 K (μeff = 5.1 µB), but decreases rapidly below this temperature most probably due to the appearance of weak antiferromagnetic interactions between Fe atoms. Additionally, analysis of Mossbauer spectra confirmed the presence of divalent Fe atoms in the structure. Thermogravimetrical and X-ray high-temperature diffraction analyses showed the thermal stability of the material up to 548 K.