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The exponential growth of greenhouse gas emissions and their associated climate change problems have motivated the development of strategies to reduce CO 2 levels via CO 2 capture and conversion. Reverse water gas shift (RWGS) reaction has been targeted as a promising pathway to convert CO 2 into syngas which is the primary reactive in several reactions to obtain high-value chemicals. Among the different catalysts reported for RWGS, the nickel-based catalyst has been proposed as an alternative to the expensive noble metal catalyst. However, Ni-based catalysts tend to be less active in RWGS reaction conditions due to preference to CO 2 methanation reaction and to the sintering and coke formation. Due to this, the aim of this work is to study the effect of the potassium (K) in Ni/CeO 2 catalyst seeking the optimal catalyst for low-temperature RWGS reaction. We synthesised Ni-based catalyst with different amounts of K:Ni ratio (0.5:10, 1:10, and 2:10) and fully characterised using different physicochemical techniques where was observed the modification on the surface characteristics as a function of the amount of K. Furthermore, it was observed an improvement in the CO selectivity at a lower temperature as a result of the K-Ni-support interactions but also a decrease on the CO 2 conversion. The 1K catalyst presented the best compromise between CO 2 conversion, suppression of CO 2 methanation and enhancing CO selectivity. Finally, the experimental results were contrasted with the trends obtained from the thermodynamics process modelling observing that the result follows in good agreement with the modelling trends giving evidence of the promising behaviour of the designed catalysts in CO 2 high-scale units., Competing Interests: The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest., (Copyright © 2021 Gandara-Loe, Portillo, Odriozola, Reina and Pastor-Pérez.)

Here we present a comprehensive study on the effect of reaction parameters on the upgrade of an acetone, butanol and ethanol mixture-key molecules and platform products of great interest within the chemical sector. Using a selected high performing catalyst, Fe/MgO-Al 2 O 3 , the variation of temperature, reaction time, catalytic loading, and reactant molar ratio have been examined in this reaction. This work is aiming to not only optimize the reaction conditions previously used, but to step toward using less energy, time, and material by testing those conditions and analyzing the sufficiency of the results. Herein, we demonstrate that this reaction is favored at higher temperatures and longer reaction time. Also, we observe that increasing the catalyst loading had a positive effect on the product yields, while reactant ratios have shown to produce varied results due to the role of each reactant in the complex reaction network. In line with the aim of reducing energy and costs, this work showcases that the products from the upgrading route have significantly higher market value than the reactants; highlighting that this process represents an appealing route to be implemented in modern biorefineries., (Copyright © 2020 Ketabchi, Pastor-Pérez, Arellano-García and Reina.)

Gold has long held the fascination of mankind. For millennia it has found use in art, cosmetic metallurgy and architecture; this element is seen as the ultimate statement of prosperity and beauty. This myriad of uses is made possible by the characteristic inertness of bulk gold; allowing it to appear long lasting and above the tarnishing experienced by other metals, in part providing its status as the most noble metal., (Copyright © 2019 Price, Pastor-Pérez, Ivanova, Reina and Liu.)