Metal-organic frameworks (MOFs) are novel microporous materials with large surface areas, porosities, and thermal stabilities. Even though many thousand MOFs have been identified, few MOF materials have been evaluated for gas mixtures separations and fuel gas storage. In this work, using grand canonical Monte Carlo simulations, we calculated adsorption isotherms of pure and binary mixtures of hydrogen-methane in two large surface area MOFs (MOF-5 and MOF-177), two catenated MOFs (IRMOF-11 and MOF-14), and a high affinity open metal site MOF with strong Zn δ+ -O δdipoles on the surface that create strong energetic interaction with the adsorbates (MOF-74). The pure and mixture adsorption isotherms were calculated at 298 K and up to pressures of approximately 80 bar. The results of this study indicate that separation of hydrogen from methane in these materials would be successful, since hydrogen in a 50% bulk mixture at low pressures has selectivities on the order of 25 for MOF-74, 20 for IRMOF-11, and 18 for MOF-14, compared to low selectivities values on the order of 5 for the two large surface area MOFs, MOF-5 and MOF-177. From this study, we also found that MOF-74 has a large methane storage capacity of 170 cm 3 (STP)/cm 3 at 298 K and 35 atm, close to the 180 cm 3 (STP)/cm 3 DOE target for practical methane storage. None of the materials studied has hydrogen gravimetric uptakes in excess of 0.4% wt.

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Three of the most frequent antitubercular agents employed against Mycobacterium tuberculosis are: Rifampicin, Isoniazid and Pyrazinamide. It has been proven that the use of these antitubercular agents together, shortens the treatment period from 12-18 months to 6 months [1]. In this work we use a new Density Functional Theory chemistry model called CHIH-DFT (Chihuahua-Heterocycles-Density Functional Theory) that reflects the mixture of Hartree Fock exchange and DFT exchange, according to a mixing parameter based on empirical rules suited for heterocyclic systems. This new chemistry model was used to calculate the molecular structure of these antitubercular compounds, as well as their infrared, UV spectra, chemical reactivity and electronic properties. The UV and infrared spectra were obtained by experimental techniques. The calculated molecular structure, UV and IR spectra values from CHIH-DFT were compared with experimentally obtained values and theoretical studies. These results are in good agreement with experimental and theoretical studies. We also predicted using the relative electrophilicity and relative nucleophilicity concepts as defined by Roy et al. [2] the chemical active sites for the three antitubercular compounds as well as their electronegativity, ionization potential, electron affinity, hardness, dipole moment, E(HOMO)-E(LUMO) gap energy, etc.

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