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Carbon capture and utilization (CCU) technologies present a promising solution for converting CO2 emissions into valuable products. Here we show how amines, such as monoethanolamine (MEA) and 2-amino-2-methyl-1-propanol (AMP), influence the electrochemical CO2 reduction process in an integrated CCU system. Using in situ spectroscopic techniques, we identify the key roles of carbamate bond strength, proton shuttling, and amine structure in dictating reaction pathways on copper (Cu) and lead (Pb) electrodes. Our findings demonstrate that on Cu electrodes, surface blockage by ammonium species impedes CO₂ reduction, whereas on Pb electrodes, proton shuttling enhances the production of hydrocarbon products. This study provides additional insights into optimizing CCU systems by tailoring the choice of amines and electrode materials, advancing the selective conversion of CO₂ into valuable chemicals. Integrated carbon capture and utilization (CCU) systems offer a sustainable approach to converting CO₂ emissions into valuable chemicals. Here, the authors report the choice of amine and electrode materials significantly impact the efficiency and selectivity of CO2 reduction in CCU processes. [ABSTRACT FROM AUTHOR]

The catalytic dehydration of glycerol to acrolein is investigated over silica-supported niobia catalysts in a continuous fixed-bed gas-phase reactor. Various supported niobia catalysts are prepared and characterized using surface analysis and spectroscopic methods (XRD, UV–Vis, XPS, N2 adsorption), as well as with ammonia adsorption microcalorimetry. Good results are obtained with initial glycerol conversions of over 70% and with 50–70% selectivity to acrolein. We investigate the influence of changing the catalyst acid strength by varying the niobia content and catalyst calcination temperature. Glycerol conversion and acrolein selectivity depend on the surface acid strength. Catalyst deactivation by coking is also observed, but simple oxidative treatment in air restores the activity of the catalysts completely. [ABSTRACT FROM AUTHOR]

In the search for new materials and concepts in materials science, metallo-organic hybrids are attractive candidates; they can combine the rich diversity of organic molecules with the advantages of metals. Transition metals such as palladium are widely applied in catalysis, and small organic molecules such as those in the cinchona alkaloid family can control the stereochemistry of a number of organic reactions. Here, we show that reducing a metal salt in the presence of a cinchona alkaloid dopant gives a chirally imprinted metallo-organic hybrid material that is catalytically active and shows moderate enantioselectivity in hydrogenation. Furthermore, using photoelectron emission spectroscopy, we show that the metal retains some chiral character even after extraction of the dopant. This simple and effective methodology opens exciting opportunities for developing a variety of chiral composite materials. [ABSTRACT FROM AUTHOR]