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The catalytic wet air oxidation of oxygenated pollutants has been investigated in a co-current downflow trickle-bed reactor, over a temperature range 423-473 K at a total pressure of 5 MPa, using a 2.8% Ru/TiO 2 catalyst. When the catalyst was employed under integral conditions (high catalyst mass/liquid flow ratio, approximate residence time of 5.1 h g Ru L -1 ) it was possible to convert 5 g L -1 aqueous solutions of cyclohexanol, succinic acid, and acetic acid into CO 2 and H 2 O. Experimental kinetic data were measured, in the reactor operating differentially at 463 K, at different conversions of succinic acid obtained at each step of the successive recycling of the reaction medium. The intermediate compounds detected were identified as acrylic and acetic acid. For the six main reactions identified, the reaction rates were described by Langmuir-Hinshelwood type rate equations, assuming competitive adsorption of liquid-phase components. The comparison of the experimental data with kinetic modeling showed an excellent agreement. The model indicates a very low adsorption of acetic acid (K ACE e 0.005 L mmol -1 ) compared to succinic and acrylic acid (K SUC ) 0.13 and K ACR ) 0.16 L mmol -1 ), even though the kinetic constants were of the same order of magnitude. Long-term experiments with this catalyst demonstrate its stability under the reaction conditions used.

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A detailed survey of the effect of moisture on the CO2/N2 permeation and separation performance of Mobile Five (MFI) zeolite membranes in view of downstream postcombustion CO2 capture applications in power plants and incinerators is presented. The membranes, displaying a nanocomposite architecture, have been prepared on α‐alumina tubes by pore‐plugging hydrothermal synthesis at 443 K for 89 h using a precursor clear solution with molar composition 1 SiO2:0.45 tetrapropylammonium hydroxide:27.8 H2O. The synthesized membranes present reasonable permeation and CO2/N2 separation properties even in the presence of high water concentrations in the gas stream. A critical discussion is also provided on the technico‐economical feasibility (i.e., CO2 recovery, CO2 purity in the permeate, module volume, and energy consumption) of a membrane cascade unit for CO2 capture and liquefaction/supercritical storage from standard flue gases emitted from an incinerator. Our results suggest that the permeate pressure should be kept under primary vacuum to promote the CO2 driving force within the membrane. © 2011 American Institute of Chemical Engineers AIChE J, 58: 3183–3194, 2012

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