The paper concentrates on the study of Mo-V-Te-Nb oxide mixtures by electron microscopy combined with catalytic investigation of these materials in the partial oxidation of propane. Surface texturing of catalyst particles composed of two phases referred to in the literature as M1 and M2 is revealed by high-resolution transmission electron microscopy of high performing catalysts. The chemical composition of the catalyst surface is modified by treatment in water to obtain a significant increment in yield of acrylic acid. A chemical realization of the site isolation concept recurring on a supramolecular arrangement of catalyst and reactant rather than on atomic site isolation is suggested. A complex Mo-V-Te-Nb-Ox precursor phase carries nanoparticles made from a network of oxoclusters active as catalyst for the conversion of propane to acrylic acid. The designed synthesis of the multielement oxide bulk and of the surface structure with a different composition than the precursor phase improved the performance by a factor of 4.

Reaction kinetics and proposed mechanism for the oxidation of propane over diluted Mo 1 -V 0.3 -Te 0.23 -Nb 0.125 -O x are described. The kinetic study allowed determination of the orders of propane disappearance, propene formation, CO x formation, and acids formation. The results show that selective oxidation of propane to propylene over this catalyst follows the Langmuir-Hinshelwood mechanism. Deep oxidation of propane to carbon dioxide is first order with respect to hydrocarbon, and partial order (0.21) with respect to oxygen. The selective oxidation of propane to acrylic acid is half order with respect to hydrocarbon and partial order (0.11) with respect to oxygen, while water does not participate directly in propane transformation. The result also shows that the overall reaction consists of three parallel process channels. One main sequence of consecutive reactions leads to the desired product.

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TiO 2-Fe 3 O 4-Bentonite photocatalytic material has been developed to inactivate of Escherichia coli. The syntheses of the TiO 2-Fe 3 O 4 based photocatalyst have been carried out by sol-gel method. The bentonite used for porous support was obtained from Pacitan, Indonesia. The photocatalyst material will capture energy of UV radiation followed by the electron excitation and oxidationreduction reactions. Because of the processes, the various types of pollutants and microorganisms can be decomposed and reduced. The electron excitation will induce the formation of hydroxyl radical and O 2. These radicals are responsible to decompose the cell wall of bacteria and further damage the bacteria's cytoplasmic membrane. Decomposing of cytoplasmic membrane causes lipid peroxidation in the membrane, and then losing their viability. It is followed by the death of bacterial cell. This study conducted a series of Escherichia coli inactivation by using photocatalyst material of TiO2-Fe 3 O 4-Bentonite which was irradiated with UV light. The photocatalytic inactivation of Escherichia coli was conducted in a reactor under ultraviolet (325 nm) exposing. The photocatalytic degradation was observed for 5 hours to determine the optimum initial bacteria concentration, intensity of UV light and also photocatalyst concentration. The inactivation kinetic was approached by Chick-Watson and Hom kinetic models. The colonies calculations were conducted by Total Plate Count. The optimum condition was achieved for 300 minutes process to reach 7 bacterial log reduction units for an average bacterial inoculum size of 3.8 × 10 4 CFU/ml. All disinfection experiments showed a non-linear bacterial inactivation kinetic profile, which is started with shoulder lag followed by a log reduction and the tailing curve. The inactivation kinetics of Escherichia coli using TiO 2-Fe 3 O 4-Bentonite photocatalytic material system satisfactorily obeyed the Hom kinetic model.