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Producing syngas and hydrogen from biofuels is a promising technology in the modern energy. In this work results of authors' research aimed at design of supported membranes for oxygen and hydrogen separation are reviewed. Nanocomposites were deposited as thin layers on Ni–Al foam substrates. Oxygen separation membranes were tested in CH 4 selective oxidation/oxi-dry reforming. The hydrogen separation membranes were tested in C 2 H 5 OH steam reforming. High oxygen/hydrogen fluxes were demonstrated. For oxygen separation membranes syngas yield and methane conversion increase with temperature and contact time. For reactor with hydrogen separation membrane a good performance in ethanol steam reforming was obtained. Hydrogen permeation increases with ethanol inlet concentration, then a slight decrease is observed. The results of tests demonstrated the oxygen/hydrogen permeability promising for the practical application, high catalytic performance and a good thermochemical stability. [Display omitted] • New MIEC materials for oxygen/hydrogen separation membranes were reviewed. • A novel design of catalytic membrane reactors was considered. • High oxygen/hydrogen permeation was demonstrated for the membranes. • Performance in fuels partial oxidation/steam reforming was reviewed. • Fine and stable catalytic performance in hydrogen/syngas production was shown. [ABSTRACT FROM AUTHOR]

A modified Pechini method involving the formation of carbon shell was proposed and used for the synthesis of the unsubstituted lanthanum and praseodymium hexaaluminates with the magnetoplumbite structure. The peculiarities of the LaAlO 3 and LaAl 11 O 18 phases' formation were studied in a wide temperature range starting from their appearance at 700 °C and finishing at 1300 °C when the complete phase formation occurs. It was found that the size of the formed hexaaluminate's crystallites is a crucial factor affecting the phase purity of the final product. The critical size of the thermodynamic stability of the LaAlO 3 phase is supposed to be 10 nm, which corresponds to the specific surface area of 90 m2/g. The use of a carbon template approach leading to the formation of a core-shell structure during the synthesis procedure allows stabilizing the oxide particles in size and preventing their agglomeration at high temperatures. Depending on the carbon template nature, the carbon content in the samples was found to be 13 wt% (low-carbon-shelled samples) and 40 wt% (high-carbon-shelled samples). In the case of high carbon content, the resulting LaAl 11 O 18 and PrAl 11 O 18 hexaaluminates possess the surface areas as high as 160 m2/g. [ABSTRACT FROM AUTHOR]

Design of oxygen and hydrogen separation membranes is the point of current interest in producing syngas from biofuels. Nanocomposites with a high mixed ionic-electronic conductivity are known to be promising materials for these applications. This work aims at studying performance of oxygen and hydrogen separation membranes based on nanocomposites PrNi 0.5 Co 0.5 O 3-δ + Ce 0.9 Y 0.1 O 2-δ and Nd 5.5 WO 11.25-δ + NiCu alloy, respectively. A high and stable performance promising for the practical application was demonstrated for these membranes. For oxygen separation membrane CH 4 conversion is up to 50% with H 2 content in the outlet feed being up to 25% at 900 °C. For reactor with hydrogen separation membrane complete EtOH conversion was achieved at T ∼ 700 °C even at the highest flow rate, and a high hydrogen permeation (≥1 ml H 2 cm−2 min−1) was revealed. • A high and stable performance was demonstrated for the membranes. • The oxygen/hydrogen permeation, syngas yield, H 2 /CO ratio meet criteria of the application. • Promising characteristics are provided by high conductivity and fast diffusion. [ABSTRACT FROM AUTHOR]