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Selective hydrogenolysis of glycerol to 1,2-propanediol is one of the options for the chemical utilization of glycerol. In this work, we synthesized sulfate-functionalized metal–organic frameworks loading palladium nanoparticles, MOF-808-SO4-Pd, as effective glycerol hydrogenolysis catalysts. The sulfate groups are responsible for the dehydration of glycerol. Subsequently, palladium nanoparticles hydrogenate the intermediates to 1,2-propanediol. The synergistic reaction between acid sites and Pd gave 93.9% selectivity of 1,2-propanediol with a reaction rate of 22.4 mmol gPd−1 h−1. Our work highlights new opportunities in using acid-functionalized MOFs as novel supports for metal nanoparticle catalysts for dual site catalysis. [ABSTRACT FROM AUTHOR]

X-ray scattering techniques provide a powerful means of characterizing the formation of nanoparticles in solution. Coupling these techniques to segmented-flow microfluidic devices that offer well-defined environments gives access to in situ time-resolved analysis, excellent reproducibility, and eliminates potential radiation damage. However, analysis of the resulting datasets can be extremely time-consuming, where these comprise frames corresponding to the droplets alone, the continuous phase alone, and to both at their interface. We here describe a robust, low-cost, and versatile droplet microfluidics device and use it to study the formation of magnetite nanoparticles with simultaneous synchrotron SAXS and WAXS. Lateral outlet capillaries facilitate the X-ray analysis and reaction times of between a few seconds and minutes can be accommodated. A two-step data processing method is then described that exploits the unique WAXS signatures of the droplets, continuous phase, and interfacial region to identify the frames corresponding to the droplets. These are then sorted, and the background scattering is subtracted using an automated frame-by-frame approach, allowing the signal from the nanoparticles to be isolated from the raw data. Modeling these data gives quantitative information about the evolution of the sizes and structures of the nanoparticles, in agreement with TEM observations. This versatile platform can be readily employed to study a wide range of dynamic processes in heterogeneous systems. [ABSTRACT FROM AUTHOR]

Nitric oxide (NO), a major atmospheric pollutant and a precursor to haze, can be removed using the denitration catalyst. Mn and Ni are commonly used as denitration catalyst additives owing to their adsorption abilities for NO and ammonia (NH3). In this study, we synthesized Mn- and Ni-loaded Pt-modified sulfated cerium oxide (PtSCe) catalysts using an impregnation method and explored the effects of these elements. The results revealed that the two elements had contrasting effects on the denitration activity of the catalysts. Mn improved the water vapor and sulfur resistance of the PtSCe sample by increasing the concentration of weak acid sites, enhancing the redox ability, and increasing the content of surface-adsorbed oxygen. The elevation in oxygen vacancies, stimulated by the presence of Ce3+ and Mn3+, swiftly replenished the reactive oxygen species, thereby sustaining the high denitration efficiency of the MnPt/SCe sample. Active sites on the catalyst surface included NH3 adsorbed on Lewis acid sites, NH4+, and –NH2, along with bridging, monodentate, and bidentate nitrate groups. Regarding the catalyst reaction mechanism, we determined that the selective catalyst reduction of NH3-SCR over MnPt/SCe followed both the Eley–Rideal and Langmuir–Hinshelwood mechanisms. These findings offer crucial insights into the intricate relationship between metals, sulfates, and carrier molecules, thus providing implications for future catalyst design. [ABSTRACT FROM AUTHOR]

A series of new monophosphine ligands containing a naphthofuran skeleton have been prepared, characterized and evaluated in palladium-catalyzed Suzuki–Miyaura coupling reactions. Using Pd2(dba)3–L6 as the catalyst the reactions were performed with high catalytic activity under mild reaction conditions and the desired coupling products were obtained in good to excellent yields. The new catalyst system also showed broad substrate adaptability and practicality for gram-scale production. [ABSTRACT FROM AUTHOR]