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A novel synthetic protocol for the direct oxidation of alkanes, including cyclic and linear ones, to give ketones and alcohols using hydrogen peroxide as terminal oxidant under ambient conditions is presented. The active catalyst for this challenging transformation is conveniently generated by combination of simple Fe salts with N‐methyl bis(picolylamine) (Me‐bpa). Utilizing picolinic acid as additive leads to improved yields of ketones and alcohols (32‐57 %). The reaction can be conveniently scaled up to multi‐g scale. [ABSTRACT FROM AUTHOR]

The combination of Fe(OTf)2 with N‐methyl bis(picolylamine) (Me‐bpa) L7 enables epoxidation of linear olefins including terminal, internal, and cyclic ones, using hydrogen peroxide as terminal oxidant under mild conditions. In the presence of picolinic acid as additive improved yields of epoxides up to 75 % have been achieved. [ABSTRACT FROM AUTHOR]

As a prerequisite elementary step, carburization of iron oxides to form iron carbides is critically important to display activity for iron‐based Fischer–Tropsch synthesis catalysts. The positive role of the Cu promoter to advocate the reduction of the iron oxides has long been known. Nevertheless, its complex influence along the carburization of catalyst precursors remains controversial. Here, we resolve this decades‐long question by using a state‐of‐the‐art in situ X‐ray diffraction (XRD) method to elucidate the multi‐role of Cu promoter in modulation of carburization rate, composition of post‐carburization samples, and morphology evolution of prepared iron carbide particles under CO/He (v/v=2 %/98 %) and H2/CO/He (v/v/v=8 %/2 %/90 %) gaseous environment, by excluding the possible interference from promoter components other than Cu. We anticipate that this study enriches current tool box in the research of a specific promoter of the Fischer‐Tropsch synthesis catalysts. In situ seeing is believing: The complex influence of Cu promoter along the carburization of iron catalyst precursors has been elucidated by using a state‐of‐the‐art in situ X‐ray diffraction (XRD) method. Particularly, the multi‐role of Cu promoter in modulation of carburization rate, composition of post‐carburization samples, and morphology evolution of prepared iron carbide particles under CO/He (v/v=2 %/98 %) and H2/CO/He (v/v/v=8 %/2 %/90 %) gaseous environment, by excluding the possible interference from promoter components other than Cu. [ABSTRACT FROM AUTHOR]

Two kinds of typical mineral-derived Cu/ZnO catalysts consisting of aurichalcite and zincian malachite were introduced for furfural hydrogenation to furfuryl alcohol (FOL) and 2-methylfuran (2-MF) in a fixed-bed reactor. Under proper reaction conditions, high yields of FOL (above 99 %) and 2-MF (94.5 %) could be obtained over the aurichalcite Cu/ZnO catalyst (AC-CZ), whereas the best yield of 2-MF was only 76.9 % (0.5 h−1) over the zincian malachite Cu/ZnO catalyst (ZM-CZ). The normalized productivity of 2-MF was 43.5 mol kgCu−1 h−1 and 17.4 mol kgCu−1 h−1 for AC-CZ and ZM-CZ, respectively (LHSV=1.5 h−1). The catalysts were characterized by XRD analysis, Raman spectra, CO IR spectroscopy, H2 temperature-programmed reduction, N2O titration, NH3 temperature-programmed desorption, and X-ray photoelectron spectroscopy. The far better performance of AC-CZ in furfural hydrogenation was ascribed to its higher dispersion of copper species, superior copper surface area, better surface acidity distribution, and stronger Cu0-ZnO synergy. In addition, the surface acidity of the catalysts seemed to have a higher influence on 2-MF production than the Cu surface area, but the optimal balance of both factors still needs to be investigated systematically. [ABSTRACT FROM AUTHOR]