Nanomaterials with oxygen mobility for catalysts of biofuels transformation into syngas, SOFC and oxygen/hydrogen separation membranes: Design and performance

Approaches to the design of efficient and stable catalysts for biofuel reforming into syngas: doping the mesoporous MgAl2O4 support with transition metal cations

“…The responses of the 18 O atomic fraction ( α ) and 16 O 18 O (or C 16 O 18 O) molecular fractions in the outlet were analyzed in order to calculate the oxygen tracer diffusion coefficient ( D *) and the surface exchange constant ( k *) values using mathematical modeling. 17,24…”

“…The responses of the 18 O atomic fraction (α) and 16 O 18 O (or C 16 O 18 O) molecular fractions in the outlet were analyzed in order to calculate the oxygen tracer diffusion coefficient (D*) and the surface exchange constant (k*) values using mathematical modeling. 17,24 To test the catalytic activity, the fraction of 0.5-0.25 mm prepared from the pelletized catalyst by crashing and sieving and diluted in a 1 : 1 wt ratio with quartz sand was taken in all cases. Before testing, the catalysts were reduced in the feed of 5% H 2 in He at 650 °C.…”

Design of Mixed Ionic-Electronic Materials for Permselective Membranes and Solid Oxide Fuel Cells Based on Their Oxygen and Hydrogen Mobility

“…Since the oxide ions’ transport across the membrane is coupled with the electron transport, a high electronic conductivity is required as well ( Figure 2 ). This allows to use such membranes for pure oxygen production as well as a part of catalytic membrane reactors for fuels transformation reactions [ 53 , 55 , 58 , 69 , 70 , 71 , 72 , 73 , 74 , 75 , 76 ].…”

“…Similar to the oxygen separation membranes, a high hydrogen mobility and surface reactivity as well as a high electronic conductivity are required for hydrogen separation membrane materials. This allows it to reach high hydrogen permeation fluxes for obtaining pure hydrogen including its production in catalytic membrane reactors for fuel transformation reactions [ 42 , 55 , 58 , 82 , 83 , 84 , 85 , 86 , 87 , 88 , 89 ]. There are advantages in using triple (H + /O 2− /e − )-conducting materials for hydrogen separation membranes, since the presence of the oxide-ionic component of the conductivity can enable the following features: Some proton transport mechanisms being mediated by the oxygen transport as will be mentioned in Section 3.2 [ 90 , 91 , 92 ]; Oxide ion counterpermeation across the membrane allows us to increase the hydrogen yield due to the water splitting reaction [ 89 , 93 , 94 ]; Triple conductivity allows to enhance the performance in various catalytic reactions and to improve gas separation properties due to the coupled transport of all types of mobile species, forcing them to be transported against their chemical potential gradient [ 95 , 96 , 97 ].…”

“…They can be used for the design of electrodes [ 29 , 30 , 31 , 32 , 33 , 34 , 35 ] and electrolytes [ 36 , 37 , 38 , 39 , 40 , 41 ] in SOFCs and for the design of gas separation membranes [ 42 , 43 , 44 , 45 , 46 ] as well as in catalytic membrane reactors [ 47 , 48 , 49 ]. Oxide materials with mixed ionic-electronic conductivity (or mixed ionic electron conductors, MIECs) are considered as a prospective class of multifunctional materials and are widely investigated for their use in both SOFCs and membrane reactors [ 50 , 51 , 52 , 53 , 54 , 55 , 56 ].…”