The Role of Ruthenium in CO2 Capture and Catalytic Conversion to Fuel by Dual Function Materials (DFM)

Development of sustainable energy technologies and reduction of carbon dioxide in the atmosphere are the two effective strategies in dealing with current environmental issues. Herein we report a Dual Function Material (DFM) consisting of supported sodium carbonate in intimate contact with dispersed Ru as a promising catalytic solution for combining both approaches. The Ru-Na2CO3 DFM deposited on Al2O3 captures CO2 from a flue gas and catalytically converts it to synthetic natural gas (i.e., methane) using H2 generated from renewable sources. The Ru in the DFM, in combination with H2, catalytically hydrogenates both adsorbed CO2 and the bulk Na2CO3, forming methane. The depleted sites adsorb CO2 through a carbonate reformation process and in addition adsorb CO2 on its surface. This material functions well in O2- and H2O-containing flue gas where the favorable Ru redox property allows RuOx, formed during flue gas exposure, to be reduced during the hydrogenation cycle. As a combined CO2 capture and utilization scheme, this technology overcomes many of the limitations of the conventional liquid amine-based CO2 sorbent technology

The Role of Ruthenium in CO2 Capture and Catalytic Conversion to Fuel by Dual Function Materials (DFM)

Development of sustainable energy technologies and reduction of carbon dioxide in the atmosphere are the two effective strategies in dealing with current environmental issues. Herein we report a Dual Function Material (DFM) consisting of supported sodium carbonate in intimate contact with dispersed Ru as a promising catalytic solution for combining both approaches. The Ru-Na2CO3 DFM deposited on Al2O3 captures CO2 from a flue gas and catalytically converts it to synthetic natural gas (i.e., methane) using H2 generated from renewable sources. The Ru in the DFM, in combination with H2, catalytically hydrogenates both adsorbed CO2 and the bulk Na2CO3, forming methane. The depleted sites adsorb CO2 through a carbonate reformation process and in addition adsorb CO2 on its surface. This material functions well in O2- and H2O-containing flue gas where the favorable Ru redox property allows RuOx, formed during flue gas exposure, to be reduced during the hydrogenation cycle. As a combined CO2 capture and utilization scheme, this technology overcomes many of the limitations of the conventional liquid amine-based CO2 sorbent technology

Ceria-based palladium zinc catalysts as promising materials for water gas shift reaction

The production of hydrogen for fuel cell applications requires several fuel processing steps, including CO removal by means of the water gas shift (WGS) and CO preferential oxidation reactions. In this work we investigate the behavior of palladium\u2013zinc supported on CeO2, Ce0.5Zr0.5O2 and ZrO2 as a promising alternative to low temperature WGS catalysts for fuel processing.WGS activity is optimized when the PdZn alloy is formed. Ceria-containingmaterials showlittle deactivation during startup\u2013shutdown cycles in reformate gas and for palladium\u2013zinc supported on pure ceria the activity can be fully recovered by an in situ reduction treatment

Ceria-based palladium zinc catalysts as promising materials for water gas shift reaction

The production of hydrogen for fuel cell applications requires several fuel processing steps, including CO removal by means of the water gas shift (WGS) and CO preferential oxidation reactions. In this work we investigate the behavior of palladium\u2013zinc supported on CeO2, Ce0.5Zr0.5O2 and ZrO2 as a promising alternative to low temperature WGS catalysts for fuel processing.WGS activity is optimized when the PdZn alloy is formed. Ceria-containingmaterials showlittle deactivation during startup\u2013shutdown cycles in reformate gas and for palladium\u2013zinc supported on pure ceria the activity can be fully recovered by an in situ reduction treatment

Evaluación mecanicista de materiales de doble función, compuestos por Ru-Ni, Na2O/Al2O3 y Pt-Ni, Na2O/Al2O3, para la captura y metanización de CO2 por DRIFTS in-situ

8 páginasRecently, different Dual Function Materials (DFM) that capture CO2 from a power plant flue gas stream with catalytic conversion to CH4 have been developed. DFMs are composed of an alkaline adsorbent and an active methanation catalyst supported on a high surface area carrier. Among the different DFMs studied, relatively inexpensive 10%Ni,6.1%“Na2O”/Al2O3 DFM (NiDFM) reported high methanation activity. However, due to rapid oxidation of Ni active sites, it is not suitable for O2-containing applications. The presence of small amounts of Ru or Pt in combination with Ni promote the reduction of NiOx rendering it active towards CO2 methanation upon the addtion of H2. Therefore, mechanistic insights of the presence of Ru or Pt with Ni DFMs during CO2 capture was investigated by in-situ Diffuse Reflectance Infrared Fourier Transform Spectroscopy (DRIFTS) under both non-oxidizing and oxidizing conditions. Under both, O2 and O2-free conditions, at 320 °C, Pt dissociates CO2 to form a CO-Pt species providing a new CO2 adsorption site on the DFM surface. The greatest NiO reduction occurrs for the 1%Ru,10%Ni,6.1%“Na2O”/Al2O3 (RuNiDFM) with a lesser effect for 1%Pt,10%Ni,6.1%“Na2O”/Al2O3 (PtNiDFM). Also, RuNiDFM gives the the best performance methanation.Recientemente, se han desarrollado diferentes materiales de función dual (DFM) que capturan CO2 de una corriente de gas de combustión de una planta de energía con conversión catalítica a CH4. Los DFM están compuestos por un adsorbente alcalino y un catalizador de metanación activo soportado en un vehículo de gran área superficial. Entre los diferentes DFM estudiados, el relativamente económico 10 % Ni, 6,1 % “Na2O”/Al2O3 DFM (NiDFM) informó una alta actividad de metanización. Sin embargo, debido a la rápida oxidación de los sitios activos de Ni, no es adecuado para aplicaciones que contienen O2. La presencia de pequeñas cantidades de Ru o Pt en combinación con Ni promueve la reducción de NiOx haciéndolo activo frente a la metanización de CO2 tras la adición de H2. Por lo tanto, los conocimientos mecánicos de la presencia de Ru o Pt con DFM de Ni durante la captura de CO2 se investigaron mediante espectroscopía de transformada de Fourier infrarroja de reflectancia difusa in situ (DRIFTS) en condiciones no oxidantes y oxidantes. Tanto en condiciones de O2 como libres de O2, a 320 °C, el Pt disocia el CO2 para formar una especie de CO-Pt que proporciona un nuevo sitio de adsorción de CO2 en la superficie del DFM. La mayor reducción de NiO ocurre para el 1%Ru,10%Ni,6,1%“Na2O”/Al2O3 (RuNiDFM) con un efecto menor para el 1%Pt,10%Ni,6,1%“Na2O”/Al2O3 (PtNiDFM). Además, RuNiDFM ofrece el mejor rendimiento de metanización