Performance of solid oxide electrolysis cells based on composite La0.8Sr0.2MnO3−δ – yttria stabilized zirconia and Ba0.5Sr0.5Co0.8Fe0.2O3−δ oxygen electrodes

The electrochemical performance of solid oxide electrolysis cells (SOECs) having barium strontium cobalt ferrite (Ba_0.5Sr_0.5Co_0.8Fe_0.2O_3−δ) and composite lanthanum strontium manganite–yttria stabilized zirconia (La_0.8Sr_0.2MnO_3−δ–YSZ) oxygen electrodes has been studied over a range of operating conditions. Increasing the operating temperature (973 K to 1173 K) significantly increased electrochemical performance and hydrogen generation efficiency for both systems. The presence of water in the hydrogen electrode was found to have a marked positive effect on the EIS response of solid oxide cell (SOC) under open circuit voltage (OCV). The difference in operation between electrolytic and galvanic modes was investigated. Cells having BSCF oxygen electrodes (Ni–YSZ/YSZ/BSCF) showed greater performance than LSM-YSZ-based cells (Ni–YSZ/YSZ/LSM-YSZ) over the range of temperatures, in both galvanic and electrolytic regimes of operation. The area specific resistance (ASR) of the LSM-YSZ-based cells remained unchanged when transitioning between electrolyser and fuel cell modes; however, the BSCF cells exhibited an overall increase in cell ASR of ∼2.5 times when entering electrolysis mode.     

Gasoline upgrading by self-etherification with ethanol on modified beta-zeolite

This research studied the modification of beta-zeolite for self-etherification process of fluidized catalytic cracking (FCC) gasoline and ethanol. The catalytic activity of reducing olefins in FCC gasoline accompanied with higher ethanol substitution was evaluated; moreover, the influences of Si/Al ratio in beta zeolite and the addition of copper (Cu) or magnesium (Mg) in the beta zeolite on the reaction performance were also investigated. It was found that the beta zeolite with Si/Al ratio of 27 (beta₂₇) can enhance higher ethanol conversion than those of 42 and 77. In addition, the modification of beta₂₇ by Cu (Cu-beta₂₇) can further improve the ethanol conversion from 38.2% (beta₂₇) to 55.1%, and the olefin content reduction from 46.2% (beta₂₇) to 62.4%. The improvement of the catalytic activity also enhances the obtained gasoline properties i.e. lower blending Reid vapor pressure (bRvp) and higher research octane number (RON).     

Steam reforming of LPG over Ni and Rh supported on Gd-CeO2 and Al2O3: Effect of support and feed composition

The steam reforming of liquefied petroleum gas (LPG) over Ni- and Rh-based catalysts supported on Gd-CeO₂ (CGO) and Al₂O₃ was studied at 750-900 °C. The order of activity was found to be Rh/CGO > Ni/CGO ∼ Rh/Al₂O₃ > Ni/Al₂O₃; we indicated that the comparable activity of Ni/CGO to precious metal Rh/Al₂O₃ is due to the occurring of gas-solid reactions between hydrocarbons and lattice oxygen () on CGO surface along with the reaction taking place on the active site of Ni, which helps preventing the carbon deposition and promoting the steam reforming of LPG.The effects of O₂ (as oxidative steam reforming) and H₂ adding were further studied over Ni/CGO and Ni/Al₂O₃. It was found that the additional of these compounds significantly reduced the amount of carbon deposition and promoted the conversion of hydrocarbons (i.e., LPG as well as CH₄, C₂H₄ and C₂H₆ occurred from the thermal decomposition of LPG) to CO and H₂. Nevertheless, the addition of too high O₂ oppositely decreased H₂ yield due to the oxidizing of Ni particle and the possible combusting of H₂ generated from the reaction, while the addition of too high H₂ also negatively affect the catalyst activity due to the occurring of catalyst active site competition and the inhibition of gas-solid reactions between the gaseous hydrocarbon compounds and on the surface of CGO (for the case of Ni/CGO).     

Synthesis and characterization of Ogataea thermomethanolica alcohol oxidase immobilized on barium ferrite magnetic microparticles

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