Kinetics of the hydrogenation of CO2 to methanol at atmospheric pressure using a Pd-Cu-Zn/SiC catalyst

The kinetics of the hydrogenation of CO2 to methanol (MeOH) at atmospheric pressure using a Pd-Cu-Zn/SiC catalyst has been analyzed. An initial sensitivity study was performed in order to evaluate the effect of reaction conditions (temperature, CO2/H2 ratio and the presence of products in the feed s...

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Detalhes bibliográficos
Autores: Díez Ramírez, Javier, Díaz-López, José Antonio, Dorado Fernández, Fernando, Sánchez Paredes, Paula
Tipo de documento: artigo
Data de publicação:2018
País:España
Recursos:Universidad de Castilla-La Mancha
Repositório:RUIdeRA. Repositorio Institucional de la UCLM
OAI Identifier:oai:ruidera.uclm.es:10578/29766
Acesso em linha:http://hdl.handle.net/10578/29766
Access Level:Acceso aberto
Palavra-chave:CO2 hydrogenation
Methanol
Langmuir–Hinshelwood
Kinetic
Descrição
Resumo:The kinetics of the hydrogenation of CO2 to methanol (MeOH) at atmospheric pressure using a Pd-Cu-Zn/SiC catalyst has been analyzed. An initial sensitivity study was performed in order to evaluate the effect of reaction conditions (temperature, CO2/H2 ratio and the presence of products in the feed stream) on the catalytic performance. The results of this study were used to develop three Langmuir–Hinshelwood kinetic models in which the adsorption term was modified (competitive vs two-site vs three-site adsorption mechanism). All of the kinetic models predicted the experimental results well and the corresponding parameters were statistically meaningful. Model discrimination revealed that the three-site adsorption mechanism led to the lowest residual sum of squares and was the only one that met all of the parameter constraints. The quality of this model was evaluated by comparing the results of additional experiments with the predicted values. The three-site adsorption mechanism agreed with the catalytic observations reported previously, where it was observed that, in the presence of a Pd-Cu-Zn/SiC catalyst, the synthesis of MeOH by hydrogenation of CO2 took place on PdZn active sites, whereas the Reverse Water Gas Shift (RWGS), which led to CO, was catalyzed by PdCu sites. The H2 dissociative adsorption was believed to take place on ZnO.