The electrochemical transformation of biomass-derived compounds (e.g., aldehyde electroreduction to alcohols) is gaining increasing interest due to the sustainability of this process that can be exploited to produce value-added products from biowastes and renewable electricity. In this framework, the electrochemical conversion of 5-hydroxymethylfurfural (HMF) to 2,5-bis(hydroxymethyl)furan (BHMF) is studied. Nanostructured Ag deposited on Cu is an active and selective electrocatalyst for the formation of BHMF in basic media. However, this catalyst deserves further research to elucidate the role of the morphology and size of the coated particles in its performance as well as the actual catalyst surface composition and its stability. Herein, Ag is coated on Cu open-cell foams by electrodeposition and galvanic displacement to generate different catalyst morphologies, deepening on the particle growth mechanism, and the samples are compared with bare Ag and Cu foams. The chemical–physical and electrochemical properties of the as-prepared and spent catalysts are correlated to the electroactivity in the HMF conversion and its selectivity toward the formation of BHMF during electroreduction. AgCu bimetallic nanoparticles or dendrites are formed on electrodeposited and displaced catalysts, respectively, whose surface is Cu-enriched along with electrochemical tests. Both types of bimetallic AgCu particles evidence a superior electroactive surface area as well as an enhanced charge and mass transfer in comparison with the bare Ag and Cu foams. These features together with a synergistic role between Ag and Cu superficial active sites could be related to the twofold enhanced selectivity of the Ag/Cu catalysts for the selective conversion of HMF to BHMF, that is, >80% selectivity and ∼ 100% conversion, and BHMF productivity values (0.206 and 0.280 mmol cm –2 h –1 ) ca. 1.5–3 times higher than those previously reported.

The electrocatalytic conversion of 5‐hydroxymethylfurfural (HMF), a biomass platform molecule, to 2,5‐bis(hydroxymethyl)furan (BHMF), a polymer precursor, is a fully sustainable route that operates at room temperature and pressure, using water as source of hydrogen, and avoids high H2 pressures. In this work, we investigate the use of 3D electrocatalysts, made by Ag0 electrodeposited on Cu open‐cell foams (Ag/Cu), to improve the efficiency in the electrochemical conversion of HMF to BHMF in basic media at different HMF concentrations. For comparison purposes, Ag and Cu bulk foams as well as Ag, Cu and Ag/Cu foil counterparts are investigated. For diluted 0.02 M HMF solutions, BHMF is selectively produced at high HMF conversion and FE over Ag/Cu foams. The large surface area of 3D Ag/Cu foams, compared to their 2D counterparts, does not affect selectivity, but increases the rate of conversion and in turn the productivity. However, it would appear that the increase in the surface area is not enough to increase the efficiency in the conversion of more concentrated HMF electrolytes (0.05–0.50 M). The productivity of Ag/Cu is modified with electrocatalytic cycles.

Ni-based catalysts are selective in the hydrogenation of CO2 to CH4 but their activity and stability need improvement. Herein, we propose a hydrotalcite-derived high loaded Ni-Al2O3 catalyst promoted by La. The effect of La on the catalyst properties is investigated and compared with that of Y and Ce. The NiOx crystallite size and basic properties (rather than the nickel reducibility) as well as the catalytic activity depend on the rare-earth element. The La-catalyst achieves a more relevant activity enhancement at low temperature and high space velocity (480 L g -1 h -1 , CO2/H2/N2 = 1/4/1 v/v), high CH4 productivity (101 LCH4 gNi -1 h -1 ) and stability, even under undiluted feeds. In situ DRIFTS and the characterization of spent catalysts confirm that this enhanced performance is related to the combination of dissociative and associative CO2 activation on more reduced, highly dispersed and stable Ni nanoparticles and basic sites in the La2O3-Al2O3 matrix, respectively.

Since July 2013 the first stand-alone Molten Salt Parabolic Trough (MSPT) plant, located adjacent to the Archimede Solar Energy (ASE) manufacturing plant in Massa Martana (Italy), is in operation.After one year of operation, the management of the ASE demonstration plant has shown that MSPT technology is a suitable and reliable option. Several O&M procedures and tests have been performed, always with very good results confirming that this approach can be easily scaled up to realize standard size CSP plants without any concern, if the plant design takes into account molten salt peculiarities. In this paper a brief description of the plant and the overall and main plant operation figures will be presented.

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