Browsing by Author "Arratibel, A."
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Item Pd-based membranes performance under hydrocarbon exposure for propane dehydrogenation processes: Experimental and modeling: Experimental and modeling(2022-03-08) Brencio, C.; Fontein, F.W.A.; Medrano, J.A.; Di Felice, L.; Arratibel, A.; Gallucci, F.; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSIn this work, a novel Pd–Ag double-skinned (DS-) membrane is used for the first time in conditions typical of propane dehydrogenation (PDH). This membrane presents a protective layer on top of the H2-selective one, which acts as shield against chemical deactivation and mechanical erosion under reaction conditions. While the protective layer is already been proven as an efficient barrier against membrane erosion in fluidized beds, there is no validation yet under PDH reaction. The DS- membrane performance is compared with a conventional (C-) Pd–Ag membrane under alkane/alkene exposure, at 400–500 °C and 3 bar, to investigate whether the incorporation of the protective layer would be suited for H2 separation in PDH systems, and if coking rate would be affected. The novel membrane shows a H2 permeance of 2.28 × 10−6 mol∙m−2 s−1∙Pa−1 at 500 ᵒC and 4 bar of pressure difference, overcoming the performance of the conventional PdAg one (1.56x∙10−6 mol m−2 s−1∙Pa−1). Both membranes present a stable H2 flux under alkane exposure, while deactivation occurs under exposure to alkenes. A model able to describe the H2 flux through Pd-based membranes is presented to fit the experimental data and predict membrane performance. The model includes mass transfer limitations in the retentate and a corrective inhibition factor to account for the competitive adsorption of hydrocarbon species in the H2 selective layer. The experimental results obtained under alkene exposure deviates from model predictions; this can be attributed to carbon deposition on the surface of the selective layer, as further detected on the DS-membrane by Scanning Electron Microscopy (SEM)/Energy Dispersive X-Ray Analysis (EDX), which is the main factor for membrane deactivation.Item Pore flow-through catalytic membrane reactor for steam methane reforming: characterization and performance(2022-07-12) Angulo, M.; Agirre, I.; Arratibel, A.; Llosa Tanco, M. A.; Pacheco Tanaka, D. A.; Barrio, V. L.; TECNOLOGÍA DE MEMBRANAS E INTENSIFICACIÓN DE PROCESOSA series of pore flow-through catalytic nonselective membrane reactors (PTCMRs) were studied for steam methane reforming (SMR) in the 500 to 900 °C temperature range under 10 barg pressure and a steam-to-carbon ratio of 5. The reactants flow through the pores of the membrane where they react on contact with the Pd nanoparticles. Various reactor configurations were prepared and tested with porous α-Al2O3-based ceramic tubes with one or more γ-Al2O3/YSZ layers on the external surface. The palladium content and dispersion affect the catalytic activity of the reactors and the results show that the efficiency of the reactions depends on the number of γ-Al2O3/YSZ layers.