摘要
The catalytic hydrogenation of D-glucose over a 3 wt% Ru/C catalyst was studied varying the operating conditions in mild conditions range to optimize the obtention of D-sorbitol. The stirring speed, temperature, pressure, and initial glucose concentration were varied between 250 - 700 rpm, 343 - 383 K, 0.5 - 2 MPa, and 0.033 - 0.133 M, respectively. To verify the absence of mass transport limitations, the diffusion of reagents in the gas-liquid interface, the liquid-solid interface, and the internal diffusion in the particles were evaluated. Under the operating conditions studied, the reaction rate showed an order with respect to H<sub>2</sub> of 0.586 and with respect to glucose of 0.406. The kinetic data were adjusted using 3 general models and 19 different sub-models based on Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetics. Model 3a was the best one interpreting the aqueous phase hydrogenation of glucose (both reagents competitively adsorbed on the catalyst). The H<sub>2</sub> adsorption is dissociative and the rate-limiting step is the surface chemical reaction.
The catalytic hydrogenation of D-glucose over a 3 wt% Ru/C catalyst was studied varying the operating conditions in mild conditions range to optimize the obtention of D-sorbitol. The stirring speed, temperature, pressure, and initial glucose concentration were varied between 250 - 700 rpm, 343 - 383 K, 0.5 - 2 MPa, and 0.033 - 0.133 M, respectively. To verify the absence of mass transport limitations, the diffusion of reagents in the gas-liquid interface, the liquid-solid interface, and the internal diffusion in the particles were evaluated. Under the operating conditions studied, the reaction rate showed an order with respect to H<sub>2</sub> of 0.586 and with respect to glucose of 0.406. The kinetic data were adjusted using 3 general models and 19 different sub-models based on Langmuir-Hinshelwood-Hougen-Watson (LHHW) kinetics. Model 3a was the best one interpreting the aqueous phase hydrogenation of glucose (both reagents competitively adsorbed on the catalyst). The H<sub>2</sub> adsorption is dissociative and the rate-limiting step is the surface chemical reaction.
作者
Juan J. Musci
María E. Chiosso
Guillermo J. Siri
Mónica L. Casella
Juan J. Musci;María E. Chiosso;Guillermo J. Siri;Mónica L. Casella(Departamento de Ciencias Básicas y Experimentales, Universidad Nacional del Noroeste de la Provincia de Buenos Aires, Junín, Argentina;Centro de Investigaciones y Transferencia del Noroeste de la Provincia de Buenos Aires (CITNOBA) - UNNOBA-UNSAdA-CONICET, Pergamino, Argentina;Centro de Investigación y Desarrollo en Ciencias Aplicadas “Dr. Jorge J. Ronco” (CINDECA) CCT CONICET-La Plata, Universidad Nacional de La Plata, Comisión de Investigaciones Científicas, La Plata, Argentina)