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The synthesis of tertiary amines from alcohols (i.e. heptanol, dodecanol, cyclohexanol, benzylalcohol) and secondary amines (Me2NH (DMA), nPr2NH, nBu2NH) has been achieved in one step using trimetallic nanoparticles (NPs) displaying a magnetic core (Co4Ni6 and Fe3Ni7) and a Cu shell as both catalysts and heating agent in the presence of an alternating magnetic field. This methodology limits the redistribution reactions occurring on amines at high temperature leading to both much higher conversion and selectivity in the absence of solvent than usually observed using conventional heating. Moreover, Co4Ni6@Cu NPs were found moisture resistant, thereby allowing for performing the reaction with commercial DMA in water (40 % wt) with again high conversion and selectivity. [ABSTRACT FROM AUTHOR]

Dehydrochlorination (DHC) is of importance for modulating the physical properties of halogenated polymers. In this work, the DHC of commercial VDF‐CTFE (vinylidene fluoride‐co‐chlorotrifluoroethylene) (10 mol % CTFE) copolymer to VDF‐DB (vinylidene fluoride with unsaturated moieties‐Double Bond) was achieved in mild reaction conditions (150 °C and 3 bar hydrogen) using different supported nickel catalysts. A complete DHC was observed within four hours of the reaction. Additionally, a certain extent (8–35 %) of hydrodefluorination (HDF) of the polymer, a challenging transformation, can also be achieved after 72 hours. A plausible mechanism based on the nuclear magnetic resonance (NMR) spectroscopy study of DHC and HDF of VDF‐CTFE was proposed. The catalyst was recyclable and stable against leaching after at least three cycles. [ABSTRACT FROM AUTHOR]

A series of bimetallic Ni10–xCox (x: 2, 3, 4, 5) nanoparticles have been prepared using the organometallic approach from Ni-[iPrNC-(CH3)-NiPr]2 and Co-[N-(SiMe3)2]2(thf) precursors. Structural characterization by high-resolution transmission electron microscopy (HR-TEM), X-ray absorption spectroscopy (XAS), and X-ray diffraction (XRD) revealed a bimetallic structure with a face-centered cubic (fcc) Ni-rich core and ultrasmall (≤2 nm) hcp Co nanoparticles decorating it. Magnetic and magnetic hyperthermia properties were measured by vibrating sample magnetometry (VSM) and calorimetry, respectively. Moreover, the Ni7Co3 composition was shown to be a stable heterogeneous catalyst for diphenyl ether (DPE) hydrogenation under magnetic induction. Remarkably, the Ni7Co3 system before and after its decoration with a small amount of Ru (1 wt %) was transposed to the low-pressure hydrogenation of lignin-linkage models and lignin-oil molecules. The results showed that the system had moderate activity in cleaving different ether C–O bonds and was effective in upgrading lignin oils through hydrodeoxygenation (HDO), with a significant preference to produce cyclohexanols. This study represents a significant step toward applications of magnetic-induced catalysis in the field of biomass valorization. [ABSTRACT FROM AUTHOR]

The Sabatier reaction activated by high-frequency magnetic fields is a promising approach for the power-to-gas process because of expected high energy efficiencies and fast switch-on times. Recent progresses have been achieved by combining nanoparticles displaying both a high heating power and a good catalytic activity. Here, we alternatively use iron microparticles associated with our own-designed Ni/CeO2 catalyst. The heating agent is cheap and abundant, and we demonstrate that the presence of eddy currents in the system improves its heating performance. The contribution of eddy currents to global heating is successfully determined by an original protocol consisting in comparing a calorimetric and a high-frequency hysteresis loop-based method to measure heating power. In addition, the optimization of the catalyst bed using SiC-spacers limits sintering and thus improves the durability of the catalyst. The energy efficiency of the catalysis process, calculated as a function of coil consumption and gas flow, is clearly improved by the use of an air-cooled Litz wire coil. These improvements are a step forward toward the development of a cheap and efficient process for chemical energy storage. [ABSTRACT FROM AUTHOR]