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Strong Lewis acid species [Al-F] were synthesized on a series of Al2O3-supported Ni catalysts modified with (0, 1, 5, and 10 wt.%) of KF to investigate the electronic and anchoring effect of [Al-F] on Ni catalysts in terms of catalytic activity, stability, and carbon resistance during dry reforming of methane (DRM) reaction. With the aids of XRD analysis, X-ray photoelectron spectroscopy, H2 temperature-programmed reduction, and in situ diffuse reflectance infrared Fourier transform spectroscopy analyses, it was found that the activity and stability of KF-modified catalysts in the reaction was directly associated to the presence of [Al-F] sites. The [Al-F] Lewis acid sites not only stabilized the metal Ni from high-temperature sintering after reaction of 200 h through an enhanced metal-support interaction, but also reduced the electron density of Ni metal, which alleviated the fast decomposition of CH4 and subsequent carbon deposition on catalysts. Balancing the rates for CH4 dissociation and carbon removal would be promising steps in the design of active and stable Ni-based catalysts. [ABSTRACT FROM AUTHOR]

CeO2-supported Rh and Co bicomponent catalysts derived from monometallic carbonyls and prepared from metal nitrates for low-temperature ethanol steam reforming (ESR) have been studied by catalytic testing using a multi-channel reactor, temperature-programmed reduction (TPR), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), H2 chemisorption, transmission electron microscopy-energy dispersive X-ray analysis (TEM-EDX), powder X-ray diffraction (PXRD) and IR spectroscopy. Reaction product analysis shows that low-temperature ESR proceeds mainly through 1) adsorbed oxametallacycle decarbonylation (OD) and acetaldehyde steam reforming (ASR) on Rh/CeO2, 2) ethanol dehydrogenation to acetaldehyde, ASR, and water-gas shift (WGS) on Co/CeO2, and 3) OD, ASR, and WGS on (Rh+Co)/CeO2. The addition of Co to Rh/CeO2 results in decreased catalytic selectivity towards CO and CH4. The carbonyl-derived (Rh+Co)/CeO2 displays marked advantage over the nitrate-prepared catalyst, leading to CO-free H2 generation with H2 yields as high as 4.3 mol [ABSTRACT FROM AUTHOR]

The Cover shows surface Lewis acid [Al–F] sites on Al2O3‐supported Ni catalysts modified with KF and its effects on Ni sintering and carbon deposition on the catalyst surface.In their Full Paper, J. Ni et al. demonstrate that the strong interaction between metal Ni and surface Lewis acid [Al–F] sites can stabilize the metal Ni from high‐temperature sintering and reduce the electron density of metal Ni, resulting in alleviating the fast decomposition of CH4 and subsequent carbon poisoning during the DRM reaction. More information can be found in the Full Paper by J. Ni et al. on page 3732 in Issue 24, 2016 (DOI: 10.1002/cctc.201601002). [ABSTRACT FROM AUTHOR]

A correction to the article "Monometallic Carbonyl-Derived CeO2- Supported Rh and Co Bicomponent Catalysts for CO-Free, High Yield H2 Generation from Low-Temperature Ethanol Steam Reforming" that was published in a previous issue is presented.