CO2 Conversion to CO by LaCo1-xFexO3 (x=0, 0.25, 0.5, 0.75, 1) Perovskite Phases at Low Temperature

FEDERICO J. POMIRO; GASTÓN G. FOUGA; ANA E. BOHÉ; GEORGINA DE MICCO

JOURNAL OF ALLOYS AND COMPOUNDS

ELSEVIER SCIENCE SA

Año: 2022

0925-8388

<span style="left: 337.5px; top: 527.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.0023);" role="presentation" dir="ltr">This paper reports conversion of CO</span><span style="left: 527.554px; top: 532.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">2</span><span style="left: 532.275px; top: 532.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 535.44px; top: 527.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(0.997381);" role="presentation" dir="ltr">to CO via reverse water-gas shift chemical looping process on LaCo</span><span style="left: 888.926px; top: 532.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">1</span><span style="left: 893.656px; top: 532.421px; font-size: 8.4px; font-family: serif;" role="presentation" dir="ltr">−</span><span style="left: 899.415px; top: 532.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">x</span><span style="left: 903.712px; top: 527.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(0.911329);" role="presentation" dir="ltr">FeO</span><span style="left: 924.864px; top: 532.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">3</span><br role="presentation" /><span style="left: 337.5px; top: 543.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.02047);" role="presentation" dir="ltr">perovskites at low temperature as a potential solution for CO</span><span style="left: 656.719px; top: 548.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">2</span><span style="left: 661.44px; top: 548.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 664.369px; top: 543.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.01622);" role="presentation" dir="ltr">mitigation. Reactions of LaCo</span><span style="left: 819.662px; top: 548.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">1</span><span style="left: 824.391px; top: 548.421px; font-size: 8.4px; font-family: serif;" role="presentation" dir="ltr">−</span><span style="left: 830.15px; top: 548.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">x</span><span style="left: 834.447px; top: 543.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(0.909706);" role="presentation" dir="ltr">Fe</span><span style="left: 846.83px; top: 548.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">x</span><span style="left: 851.127px; top: 543.171px; font-size: 12px; font-family: sans-serif;" role="presentation" dir="ltr">O</span><span style="left: 859.896px; top: 548.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">3</span><span style="left: 864.617px; top: 548.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 867.546px; top: 543.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(0.994284);" role="presentation" dir="ltr">phases with</span><br role="presentation" /><span style="left: 337.5px; top: 559.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.04832);" role="presentation" dir="ltr">x = 0, 0.25, 0.5, 0.75, 1 under hydrogen atmospheres, and subsequently, carbon dioxide, were investigated by</span><br role="presentation" /><span style="left: 337.5px; top: 575.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.06033);" role="presentation" dir="ltr">in-situ high-temperature X-ray powder diffraction and thermogravimetry. The perovskites show linear thermal</span><br role="presentation" /><span style="left: 337.5px; top: 591.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.01385);" role="presentation" dir="ltr">expansion up to around 250 ºC under hydrogen atmosphere, followed by a phase change due to formation of oxy-</span><br role="presentation" /><span style="left: 337.5px; top: 607.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.03635);" role="presentation" dir="ltr">gen vacancies, and finally, the materials decompose into La</span><span style="left: 656.719px; top: 612.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">2</span><span style="left: 661.465px; top: 607.171px; font-size: 12px; font-family: sans-serif;" role="presentation" dir="ltr">O</span><span style="left: 670.235px; top: 612.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">3</span><span style="left: 674.955px; top: 612.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 678.809px; top: 607.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.04842);" role="presentation" dir="ltr">and metallic Co/Fe. Incorporating Fe improves</span><br role="presentation" /><span style="left: 337.5px; top: 623.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.01804);" role="presentation" dir="ltr">the stability of the reduced phase. Partial reduction and decomposition temperatures under hydrogen were deter-</span><br role="presentation" /><span style="left: 337.5px; top: 639.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.04378);" role="presentation" dir="ltr">mined. After reduction of the perovskite samples, reactions with CO</span><span style="left: 702.422px; top: 644.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">2</span><span style="left: 707.143px; top: 644.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 711.016px; top: 639.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.00335);" role="presentation" dir="ltr">were analyzed. CO</span><span style="left: 811.368px; top: 644.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">2</span><span style="left: 816.088px; top: 644.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 819.962px; top: 639.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(0.985857);" role="presentation" dir="ltr">conversion increases</span><br role="presentation" /><span style="left: 337.5px; top: 655.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.06434);" role="presentation" dir="ltr">with Fe loading, with LaCo</span><span style="left: 482.266px; top: 660.349px; font-size: 8.4px; font-family: sans-serif; transform: scaleX(0.984014);" role="presentation" dir="ltr">0.50</span><span style="left: 498.828px; top: 655.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(0.909706);" role="presentation" dir="ltr">Fe</span><span style="left: 511.211px; top: 660.349px; font-size: 8.4px; font-family: sans-serif; transform: scaleX(0.984014);" role="presentation" dir="ltr">0.50</span><span style="left: 527.774px; top: 655.171px; font-size: 12px; font-family: sans-serif;" role="presentation" dir="ltr">O</span><span style="left: 536.543px; top: 660.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">3</span><span style="left: 541.264px; top: 660.349px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 544.971px; top: 655.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.04289);" role="presentation" dir="ltr">being the material with optimal balance between RWGS-CL activity and</span><br role="presentation" /><span style="left: 337.5px; top: 671.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.0244);" role="presentation" dir="ltr">long-term stability during five cycles. It reaches a maximum CO yield of 0.25 mol(mol</span><span style="left: 786.625px; top: 676.349px; font-size: 8.4px; font-family: sans-serif; transform: scaleX(0.962661);" role="presentation" dir="ltr">perovskite</span><span style="left: 825.141px; top: 671.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(0.959063);" role="presentation" dir="ltr">·cycle)</span><span style="left: 858.911px; top: 670.364px; font-size: 8.4px; font-family: serif;" role="presentation" dir="ltr">−</span><span style="left: 864.665px; top: 670.292px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">1</span><span style="left: 869.385px; top: 670.292px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 872.112px; top: 671.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(0.984212);" role="presentation" dir="ltr">and a max-</span><br role="presentation" /><span style="left: 337.5px; top: 687.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.0532);" role="presentation" dir="ltr">imum rate of 3.9 mmol(mol</span><span style="left: 485.82px; top: 692.349px; font-size: 8.4px; font-family: sans-serif; transform: scaleX(0.962665);" role="presentation" dir="ltr">perovskite</span><span style="left: 524.336px; top: 687.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.00773);" role="presentation" dir="ltr">·min)</span><span style="left: 551.758px; top: 686.364px; font-size: 8.4px; font-family: serif;" role="presentation" dir="ltr">−</span><span style="left: 557.512px; top: 686.292px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr">1</span><span style="left: 562.233px; top: 686.292px; font-size: 8.4px; font-family: sans-serif;" role="presentation" dir="ltr"> </span><span style="left: 565.762px; top: 687.171px; font-size: 12px; font-family: sans-serif; transform: scaleX(1.00414);" role="presentation" dir="ltr">at 550 °C.</span>