Hydrogen production by methane tri-reforming process over Ni-ceria catalysts: Effect of La-doping

摘要

The objective of the present work is the study of CH4 tri-reforming process (simultaneous carbon dioxide reforming, steam reforming and oxygen reforming) that can contribute to the CO2 abatement producing synthesis gas with the desiderate H2/CO ratio.A series of Ni-CeO2 catalysts with different La loadings is prepared by combustion synthesis and tested as catalysts in CH4 Tri-reforming reaction at 800 ℃ under atmospheric pressure with a GHSV of 30,000 h~(-1).It has been found that during tri-reforming reaction the activity of Ni-ceria catalysts can be enhanced by an appropriate amount of La doping (10at.%), the CH4 and CO2 conversion increases from 93% and 83% to 96% and 86.5%, respectively. The activity enhancement appears to be related to synergic effect of nickel-lanthana-surface oxygen vacancies of ceria via interfacial active sites that contribute to increase the nickel dispersion and create a basic site distribution on the surface able to interact with CO2.