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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

In France, MSW incineration bottom ash disposal calls for physico-chemical tests and depending on the results the bottom ashes are sorted into different classes allowing the reuse or not. However this study shows that there is no direct correlation between the physico-chemical testings, like leaching, soluble fraction and heavy metal content, and the environmental impact, in terms of biological toxicity. Based on the results of several ecotoxicity testings and their biotest response we define an "ecotoxicity index" and demonstrate there is a correlation between the carboxylic acids amount and the ecotoxicologic index for the bottom ashes. This clearly shows that at least organic carbon characterisation in the bottom ash is needed in addition to leaching and physico-chemical testings if one wants to have a coherent sorting procedure for the bottom ashes.

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Preparation of Mn/TiO2, Mn-Fe/TiO2, and Mn-Fe-Ce/TiO2 by the deposition-precipitation (DP) method can afford very active catalysts for low-temperature NH3-SCR (selective catalytic reduction of NO with NH3). The effect of precursor choice (nitrate vs. acetate) of Mn, Fe, and Ce on the physiochemical properties including thermal stability and the resulting SCR activity were investigated. The resulting materials were characterized by N2-Physisorption, XRD (Powder X-ray diffraction), XPS (X-ray photoelectron spectroscopy), H2-TPR (temperature-programmed reduction with hydrogen), and the oxidation of NO to NO2 measured at 300 °C. Among all the prepared catalysts 5MnAce/Ti, 25Mn0.75AceFe0.25Nit/Ti, and 25Mn0.75AceFe0.20NitCe0.05Ace/Ti showed superior SCR activity at low temperature. The superior activity of the latter two materials is likely attributable to the presence of amorphous active metal oxide phases (manganese-, iron- and cerium-oxide) and the ease of the reduction of metal oxides on TiO2. Enhanced ability to convert NO to NO2, which can promote fast-SCR like pathways, could be another reason. Cerium was found to stabilize amorphous manganese oxide phases when exposed to high temperatures.