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The combined steam/dry reforming (S/DR) technology was used to produce syngas from clean biogas. In the reaction conditions proposed, the catalytic bed can produce, without deactivation, a syngas with a H 2 /CO ratio of ≈2 directly processable for methanol or Fischer−Tropsch syntheses. Starting from the laboratory data obtained in the industrial conditions, mass and energy balances for the overall process were obtained from Aspen HYSYS simulations. The environmental evaluation was performed by applying the life cycle assessment (LCA) methodology, comparing different scenarios to the current industrial route to produce syngas (autothermal reforming or ATR of natural gas). The analysis showed that clean biogas-to-syngas technology using reforming processes has the potential to reduce the anthropogenic impact on the environment. The ReCiPe method showed that when the combined S/DR process is conducted using clean biogas also as a heat source, the CO 2 balance turns negative, ensuring that the whole process has excellent potential as carbon capture and utilization (CCU) technology providing the lowest damage in all categories. Its improvement would make it possible to further reduce the environmental burden of the overall process, which is essential for achieving sustainable development.

In recent years, the upgrading of lignocellulose bio-oils from fast-pyrolysis by means of ketonization has emerged as a frontier research domain to produce a new generation of biofuels. Propionic acid (PA) ketonization is extensively investigated as a model reaction over metal oxides, but the activity of other materials, such as metal phosphates, is mostly unknown. Therefore, PA ketonization was preliminarily investigated in the gas phase over both phosphates and oxides of Al, Zr, and La. Their catalytic activity was correlated to the physicochemical properties of the materials characterized by means of XRD, XRF, BET N2 porosimetry, and CO2- and NH3-TPD. Noteworthy, monoclinic ZrO2 proved to be the most promising candidate for the target reaction, leading to a 3-pentanone productivity as high as 5.6 h−1 in the optimized conditions. This value is higher than most of those reported for the same reaction in both the academic and patent literature.

The combined steam/dry reforming of clean biogas (CH4/CO2 = 50/50 v/v) represents an innovative way to produce synthesis gas (CO + H2) using renewable feeds, avoiding to deplete the fossil resources and increase CO2 pollution. The reaction was carried out to optimize the reaction conditions for the production of a syngas with a H2/CO ratio suitable for the production of methanol or fuels without any further upgrading. Ni-Rh/Mg/Al/O catalysts obtained from hydrotalcite-type precursors showed high performances in terms of clean biogas conversion due to the formation of very active and resistant Ni-Rh bimetallic nanoparticles. Through the utilization of a {Ni10Rh(CO)19}{(CH3CH2)4N}3 cluster as a precursor of the active particles, it was possible to promote the Ni-Rh interaction and thus obtain low metal loading catalysts composed by highly dispersed bimetallic nanoparticles supported on the MgO, MgAl2O4 matrix. The optimization of the catalytic formulation improved the size and the distribution of the active sites, leading to a better catalyst activity and stability, with low carbon deposition with time-on-stream.