Catalyst Deactivation And Regeneration Processes In Biogas Tri-Reforming Process. The Effect Of Hydrogen Sulfide Addition

This work studies Ni-based catalyst deactivation and regeneration processes in the presence of H2S under a biogas tri-reforming process for hydrogen production, which is an energy vector of great interest. 25 ppm of hydrogen sulfide were continuously added to the system in order to provoke an observ...

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Detalles Bibliográficos
Autores: Izquierdo Ereño, Urko, García García, Iker, Gutiérrez, Ángel María, Arraibi Dañobeitia, Juan Ramón, Barrio Cagigal, Victoria Laura, Cambra Ibáñez, José Francisco, Arias Ergueta, Pedro Luis
Tipo de recurso: artículo
Fecha de publicación:2018
País:España
Institución:Universidad del País Vasco
Repositorio:Addi. Archivo Digital para la Docencia y la Investigación
OAI Identifier:oai:addi.ehu.eus:10810/27705
Acceso en línea:http://hdl.handle.net/10810/27705
Access Level:acceso abierto
Palabra clave:hydrogen
reforming
deactivation
regeneration
biogas
renewable energy
synthesis gas
carbon-dioxide
model biogas
steam
methane
fuel
H2S
NI
reactors
Descripción
Sumario:This work studies Ni-based catalyst deactivation and regeneration processes in the presence of H2S under a biogas tri-reforming process for hydrogen production, which is an energy vector of great interest. 25 ppm of hydrogen sulfide were continuously added to the system in order to provoke an observable catalyst deactivation, and once fully deactivated two different regeneration processes were studied: a self-regeneration and a regeneration by low temperature oxidation. For that purpose, several Ni-based catalysts and a bimetallic Rh-Ni catalyst supported on alumina modified with CeO2 and ZrO2 were used as well as a commercial Katalco 57-5 for comparison purposes. Ni/Ce-Al2O3 and Ni/Ce-Zr-Al2O3 catalysts almost recovered their initial activity. For these catalysts, after the regeneration under oxidative conditions at low temperature, the CO2 conversions achieved79.5% and 86.9%, respectivelywere significantly higher than the ones obtained before sulfur poisoning66.7% and 45.2%, respectively. This effect could be attributed to the support modification with CeO2 and the higher selectivity achieved for the Reverse Water-Gas-Shift (rWGS) reaction after catalysts deactivation. As expected, the bimetallic Rh-Ni/Ce-Al2O3 catalyst showed higher resistance to deactivation and its sulfur poisoning seems to be reversible. In the case of the commercial and Ni/Zr-Al2O3 catalysts, they did not recover their activity.