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An experimental strategy was developed to obtain transparent Si-Al-Ti-Ni-Mo and Si-Zr-Ti-Ni-Mo sols via the sol-gel process. The sol was prepared from Si(OEt)4 (TEOS), Al(OBus)3 (OBus: C2H5CH(CH3)O), Ti(OEt)4 (OEt: OCH2CH3), Zr(OPrn)4 (OPrn: OCH2CH2CH3). In both cases nickel nitrate hexahydrate (Ni(NO3)2 · 6H2O) and ammonium heptamolybdate tetrahydrate ((NH4)6Mo7O24 · 4H2O) were the Ni and Mo sources, respectively. The sols were characterized by Fourier Transform Infrared Spectroscopy (FTIR). Assignments of the simultaneous formation of the Si-O-Al, Si-O-Ti, Si-O-Ni, and Si-O-Zr bonds were done. The sols were polymerized at room temperature (293 K) to obtain gels, and these were dried at 423 K and calcined at 573, 853 and 893 K in air. The characterization techniques used were small-angle X-ray scattering (SAXS), X-ray diffraction (XRD), scanning electron microscopy (SEM), and 29Si and 27Al magic angle spinning nuclear magnetic resonance (MAS NMR). The density of the solids was measured following ASTM method D-4892 and the porosity and surface area were determined by N2 adsorption/desorption isotherms. The corresponding average pore diameters were evaluated using the BJH, HK, and DA methods.

Using the total pressure method, phase equilibria for the n-Pentane-βmetoxipropionitrile system has been measured at temperatures of 37.8 and 43.3 °C. Data has been correlated with NRTL and Modified Wilson solution models. Coefficients for both models were obtained using the Barker method and are reported for both temperatures.