Flame-pyrolysis-prepared catalysts for the steam reforming of ethanol

Abstract

An innovative flame pyrolysis method has been employed for the preparation of Ni-based catalysts for the steam reforming of ethanol. Titania and lanthana supports, characterized by variable acidity and Ni loading have been compared, as well as different procedures to add the Ni active phase to the support, affecting metal dispersion. Samples characterization evidenced that the one pot preparation of the catalyst by flame pyrolysis resulted in the formation of a mixed oxide phase and, thus, in higher Ni dispersion even at the highest loading. The metal-support interaction was also strengthened when preparing the samples by FP than by conventional impregnation.Steam reforming at 750°C resulted in full ethanol conversion without byproducts, so that a fuel processor able to feed a 5 kWe + 5 kWt fuel cell may operate with ca. 1.35 kg of catalyst.Tests at lower temperature were also carried out, focusing on the optimization of the resistance to coking.The best results at 500°C were achieved for the FP-prepared sample supported over La2O3 and containing 15 wt% Ni as active phase.

Semi‐Batch Photocatalytic Reduction of Nitrates: Role of Process Conditions and Co‐Catalysts

“…Furthermore, higher concentration of anatase and rutile (anatase: 65 % and rutile: 35 %) interface boundary exists for FSP, which can favor the charge separation across the interface of the two phases. Last but not the least, the flame spray pyrolysis technique, imposes more crystalline defects in the structure of nanoparticles with typically fully oxidized and highly crystalline morphology, due to the abundance of oxygen and high temperature in the synthesis procedure . The surface defects are advantageous for catalytic and photocatalytic reactions, since these are the surface energetic facets with minimal charge recombination centers and electron‐hole pair charge trapping (deep traps) …”

“…Last but not the least, the flame spray pyrolysis technique, imposes more crystalline defects in the structure of nanoparticles with typically fully oxidized and highly crystalline morphology, due to the abundance of oxygen and high temperature in the synthesis procedure. [28,48,49,66] The surface defects are advantageous for catalytic and photocatalytic reactions, since these are the surface energetic facets with minimal charge recombination centers and electron-hole pair charge trapping (deep traps). [67] At pH 5.1 nitrates adsorption is favored on the nearly neutral surface of the FSP catalyst, which may be one of the factors for demonstrating the maximum conversion.…”

Modern Ni and Pd–Ni Catalysts Supported on Sn–Al Binary Oxide for Oxy‐Steam Reforming of Methanol

“…Typical catalytic systems extensively used in reforming of alcohol are copper‐based systems supported on mono‐ and binary oxides . The high activity of nickel catalysts in the steam reforming reaction to hydrogen generation was reported in the literature . Furthermore, copper catalysts are promoted by palladium in order to improve selectivity to hydrogen generation due to the ability to improve the reducibility of the active phase component and formation of intermetallic alloys .…”

“…[8][9][10][11][12][13] The high activity of nickel catalysts in the steam reforming reaction to hydrogen generation was reported in the literature. [14][15][16][17][18] Furthermore, copper catalysts are promoted by palladium in order to improve selectivity to hydrogen generation due to the ability to improve the reducibility of the active phase component and formation of intermetallic alloys. [8] Bobadilla et al [19] investigated the influence of Sn addition on catalytic activity of Ni/CeO 2 -MgO-Al 2 O 3 catalysts in steam reforming of methanol.…”

High Pressure Photoreduction of CO₂: Effect of Catalyst Formulation, Hole Scavenger Addition and Operating Conditions

“…Flame spray pyrolysis allows the synthesis of titanium dioxide nanoparticles characterized by high surface area and high thermal stability [28,[49][50][51]. Due to the abundance of oxygen and high temperature in the FSP reactor, the nanoparticles produced by FSP are typically fully oxidized and highly crystalline.…”