The present work explores the reaction pathways of γ-valerolactone (GVL) over a supported ruthenium catalyst. The conversion of GVL in aqueous phase over a 5% Ru/C catalyst was investigated in a batch reactor operating at 463K under 500-1000 psi of H 2 . The main reaction products obtained under these conditions were 2-butanol (2-BuOH), 1,4-pentanediol (1,4-PDO), 2-methyltetrahydrofuran (2-MTHF) and 2-pentanol (2-PeOH). A complete reaction network was developed, identifying the primary and/or secondary products. In this reaction network, production of 2-BuOH via decarbonylation of a ring-opened surface intermediate CH 3 CH(O*)-(CH 2 ) 2 -CO* is clearly the dominant pathway. From the evolution of products as a function of reaction time and theoretical (DFT) calculations, a mechanism for the formation of intermediates and products is proposed. The high sensitivity of 2-BuOH production to the presence of CO, compared to a much lower effect on the production of the other products indicates that the sites responsible for decarbonylation are particularly prone to CO adsorption and poisoning. Also, since the decarbonylation rate is not affected by the H 2 pressure it is concluded that the direct decarbonylation path of the CH 3 CH(O*)-(CH 2 ) 2 -CO* intermediate does not required a previous dehydrogenation step, as is the case in decarbonylation of short alcohols.

Proton‐exchange membrane fuel cells are of great interest for vehicular applications. A highly pure, sustainably obtained H2 stream is desirable to use as the cell feed. In the water gas shift (WGS) process, large amounts of CO, which is a poison for the cell anode, are removed from a bioalcohol‐derived H2 stream before it enters the cell. In this study, Cu–Ni catalysts supported on La‐doped ceria were analyzed and studied in the WGS reaction. The supports were prepared by the urea thermal decomposition method with different percentages of La as a promoter of ceria. The metal phase was incorporated by incipient wet impregnation. Many characterization techniques were employed in this work (BET, XRD, SEM, ICP, TPR, OSC), and the relationship between the resulting properties and catalytic performance was investigated to determine the effect of La. A mixture of Cu and Ni was found to be the most effective active phase, having considerable activity and selectivity towards the desired reaction. Low degrees of La doping in ceria enhance oxygen mobility in the lattice. A commercial Ce salt containing La as its main impurity (ca. 2 %) is a convenient precursor, given its good performance and low cost compared to a high‐purity salt.

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