Hydrogen production from glycerol reforming in liquid (aqueous phase reforming, APR) and vapor (steam reforming SR) phase over alumina-supported nickel catalysts modified with Ce, Mg, Zr and La was studied. Characterization of catalysts by temperature programmed reduction and XPS analyses revealed important structural effects: (i) the intercalation of Mg between nickel and alumina that inhibited the alumina incorporation to nickel phases, (ii) the close contact between Ni and Zr phases and, (iii) the close surface interaction of La and Ce ions with NiO phases. The catalytic activity of the samples studied in this work clearly indicated the different catalyst functionalities necessary to carry out aqueous-phase and vaporphase steam reforming of glycerol. For aqueous phase reforming of glycerol, the addition of Ce, La and Zr to Ni/ Al 2 O 3 improves the initial glycerol conversions obtained over the Ni/Al 2 O 3 supported catalyst. It is suggested that the differences in catalytic activities are related with geometric effects caused by the decoration of Ni phases by Ce and La or by the close interaction between Ni and Zr. In spite that nickel catalysts showed high APR activities at initial times on stream, all samples showed, independently of support, important deactivation rates that deactivate the catalysts after few hours under operation. Catalysts characterization after APR showed the oxidation of the active metallic Ni during reaction as the main cause of the observed deactivation. In the case of the glycerol steam reforming in vapor phase, the use of Ce, La, Mg and Zr as promoters of Ni based catalysts increases the hydrogen selectivity. Differences in activity were explained in terms of enhancement in: surface nickel concentration (Mg), capacity to activate steam (Zr) and stability of nickel phases under reaction conditions (Ce and La).

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Two 3D-hybrid monolithic catalysts containing immobilized copper and palladium species on a silica support were synthesized by 3D printing and a subsequent surface functionalization protocol. The resulting 3D monoliths provided a structure with pore sizes around 300 μm, high mechanical strength, and easy catalyst recyclability. The devices were designed to perform heterogeneous multicatalytic multicomponent reactions (MMCRs) based on a copper alkyne–azide cycloaddition (CuAAC) + palladium catalyzed cross-coupling (PCCC) strategy, which allowed the rapid assembly of variously substituted 1,2,3-triazoles using a mixture of tBuOH/H2O as solvent. The reusable multicatalytic system developed in this work is an example of a practical miniaturized and compartmental heterogeneous 3D-printed metal catalyst to perform MMCRs for solution chemistry.

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