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This study explores the performances of nickel‐based materials for the dry reforming of methane (DRM), an important process for hydrogen and syngas productions. Ni nanoparticles are issued from porous phyllosilicate phase exolution under reducing conditions (in situ or ex situ). Phyllosilicate precursors were obtained by deposition/precipitation with urea onto SBA‐15 porous silica, with metal loading up to 40 wt.%. Reaction was performed at 600–700 °C. The successful formation and stabilization of highly dispersed nanoparticles (2–6 nm) is revealed, even for highly loaded formulations (20 wt.% and 40 wt.%). In DRM‐700 (CH4/CO2=1, 20 % CH4, 480,000 mL gcat−1 h−1) the formulation at 20 wt.% metal loading (Ni_20 %) activated during reaction affords 50 % and 65 % of CH4 and CO2 conversions respectively at 700 °C. Ni_20 % is showing excellent resistance toward sintering after DRM stability test of 80 h. Characterizations made for spent catalyst show high resistance toward sintering and limited carbon formation. [ABSTRACT FROM AUTHOR]

Hybrid catalysis, which combines chemo‐ and biocatalytic benefits, is an efficient way to address green chemistry principles. 5‐Hydroxymethylfurfural (HMF) is a versatile building block in numerous industrial applications. To date, few studies have described the production of its amine derivatives and their polymers. Finding a good methodology to directly transform HMF to 5‐aminomethyl‐2‐furancarboxylic acid (AMFC) therefore represents an important challenge. After selecting the best oxidation catalyst for HMF conversion to 5‐aldehyde‐2‐furancarboxylic acid and immobilizing a transaminase onto a solid carrier, we implemented the first one‐pot/two‐steps hybrid catalytic process to produce AMFC (77 % yield); this is the most efficient AMFC catalytic production method from HMF reported to date. This process also produced 2,5‐furandicarboxylic acid (21 % yield) as a major secondary product that can be applied to polymer syntheses such as polyethylene furanoate. Herein, we report a novel way to access new biosourced polymers based on HMF oxidized and aminated derivatives. [ABSTRACT FROM AUTHOR]

SBA-15 catalysts doped with variable aluminum amounts were prepared through a facile evaporation-induced self-assembly process. The textural properties and acidity of the catalysts could be tuned simply by varying the aluminum content. The genesis of acid sites with weak and medium strength during reaction was directly correlated to the catalytic activity for the dehydration of 1,3-butanediol into butadiene (BD). The best performance was achieved over an Al-SBA-15 sample with a silica/alumina ratio of 76, exhibiting a stable BD yield of 59 % at temperatures as low as 200 °C. [ABSTRACT FROM AUTHOR]

A Pd/CeO2 catalyst with a prominent reversible H2 storage capacity revealed a high activity and selectivity in the direct amination of benzyl alcohol with aniline and ammonia via the borrowing hydrogen mechanism. [ABSTRACT FROM AUTHOR]

The role of the crystalline phase of Mo3VO x in the catalytic oxidation of allyl alcohol over four kinds of crystalline (orthorhombic, trigonal, tetragonal, amorphous) Mo3VO x catalysts was investigated to determine the active sites for the reactions. Tetragonal Mo3VO x was found less active for the formation of acrylic acid from allyl alcohol, although acrolein was obtained selectively at higher temperature. For orthorhombic and trigonal Mo3VO x catalyst, allyl alcohol converted to acrolein and propanal competitively at the mouth of the heptagonal channel over the a- b plane of the rod-type crystalline particles, and these aldehydes were oxidized consecutively to acrylic acid. Acrylic acid was formed effectively at increased reaction temperature over orthorhombic, trigonal and amorphous Mo3VO x catalysts, and the maximum yields of acrylic acid were 73 % for the orthorhombic Mo3VO x catalyst and 72 % for the trigonal Mo3VO x catalyst at 350 °C. [ABSTRACT FROM AUTHOR]

Solids composed of TiO2 nano-crystallites (10-40 wt %) dispersed in an SBA-15 matrix were synthesised and used as hydrodesulfurisation (HDS) active-phase supports. Well-dispersed polymolybdate species were detected by Raman spectroscopy on all the CoMo-based oxidic precursors. Undesirable bulk CoMoO4 mixed oxide was also detected on the surface of low-TiO2-content materials, which suggests the enhancement of the Mo oxidic species dispersion as a result of the presence of TiO2. After activation under H2/H2S, the obtained catalysts were tested in the HDS of thiophene. An optimum conversion was observed for the catalyst supported on the solid that contained 20 wt % TiO2, which outperformed the homologous samples supported on TiO2 and SBA-15. This clearly highlights the beneficial effect of using such nano-TiO2-SBA-15 composite supports, in which SBA-15 confers adequate textural properties to the system, and the active phase benefits from the dispersive effect of TiO2. [ABSTRACT FROM AUTHOR]

CeNi XH ZO Y nano-oxyhydride catalysts were developed for the highly efficient sustainable hydrogen production from ethanol and water in the oxidative steam reforming reaction. After an in situ treatment in hydrogen in the temperature range of 200-300 °C, the cerium-nickel binary mixed oxides became hydrogen reservoirs, which were called oxyhydrides, in the presence of hydrogen species of the hydride nature in the anionic vacancies of mixed oxides. A novel technology was developed for the room temperature hydrogen production by using the chemical energy released from the reaction between CeNi XH ZO Y nano-oxyhydride catalysts and oxygen, which completely converted ethanol specifically at 60 °C (oven temperature) and simultaneously produced hydrogen, carbon dioxide, and carbon monoxide along with small amounts of methane and ethanal. CeNi XH ZO Y nano-oxyhydride catalysts demonstrated excellent catalytic stability, which was attributed to the graphitic filamentous carbon formed during the reaction. The unique activation phenomenon of the reaction (a huge variation in the temperature between the catalyst bed and the oven) was demonstrated in detail. Finally, the correlations among the catalyst properties, the catalytic performances, and the characterizations were thoroughly discussed. [ABSTRACT FROM AUTHOR]

Keywords: 5-aminomethyl-2-furancarboxylic acid; 5-hydroxymethylfurfural; biocatalysis; enzyme catalysis; heterogeneous catalysis; hybrid catalysis; platinum; transaminase EN 5-aminomethyl-2-furancarboxylic acid 5-hydroxymethylfurfural biocatalysis enzyme catalysis heterogeneous catalysis hybrid catalysis platinum transaminase 5 5 1 01/18/21 20210112 NES 210112 B The Cover Feature b shows that hybrid catalysis is a very promising concept that combines chemical catalysts and biocatalysts in one-pot processes. In their Full Paper, A. Lancien et al. report a transaminase coupled to a platinum nanoparticle, both supported on silica, for the efficient conversion of I 5 i -hydroxymethylfurfural into I 5 i -aminomethyl- I 2 i -furancarboxylic acid. 5-aminomethyl-2-furancarboxylic acid, 5-hydroxymethylfurfural, biocatalysis, enzyme catalysis, heterogeneous catalysis, hybrid catalysis, platinum, transaminase. [Extracted from the article]

Taking alcohol from the nanobar The cover picture shows the use of nickel and cerium nano‐oxyhydride catalysts in hydrogen production from ethanol in the presence of water and oxygen. In their Full Paper on p. 2207 ff., L. Jalowiecki‐Duhamel et al. describe the characterization and catalytic properties of the nano‐compounds. Hydrogen production (45 mol %) and total conversion of ethanol remain almost constant over at least 75 h time‐on‐stream with only a small energy input (reaction in oven at 60 °C), thanks to the presence of hydride species stored in the solid. [ABSTRACT FROM AUTHOR]