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Selective catalytic reduction of NOx by ammonia (NH3-SCR) was the most efficient and economic technology for De-NOx applications. Therefore, a series of MnOx/vermiculite (VMT) and MnOx-Fe2O3/VMT catalysts were prepared by an impregnation method for the selective catalytic reduction (SCR) of nitrogen oxides (NOx). The MnOx-Fe2O3/VMT catalysts provided an excellent NO conversion of 96.5% at 200 °C with a gas hourly space velocity (GHSV) of 30,000 h-1 and an NO concentration of 500 ppm. X-ray photoelectron spectroscopy results indicated that the Mn and Fe oxides of the MnOx-Fe2O3/VMT catalyst were mainly composed of MnO2 and Fe2O3. However, theMnO2 and Fe2O3 components were well dispersed because no discernibleMnO2 and Fe2O3 phases were observed in X-ray powder diffraction spectra. Corresponding MnOx-Fe2O3/VMT monolithic honeycomb catalysts (MHCs) were prepared by an extrusion method, and theMHCs achieved excellent SCR activity at low temperature, with an NO conversion greater than 98.6% at 150 °C and a GHSV of 4000 h-1. In particular, theMNOx-Fe2O3/VMTMHCs provided a good SCR activity at roomtemperature (20 °C), with an NO conversion of 62.2% (GHSV = 1000 h-1). In addition, the NO reduction performance of theMNOx-Fe2O3/VMTMHCs also demonstrated an excellent SO2 resistance. [ABSTRACT FROM AUTHOR]

Abstract: The olivine-structured LiMPO4 (M=Fe, Mn, Co and Ni), particularly LiFePO4, is one of the most viable and promising candidates of cathode material for the sustainable lithium ion batteries (LIBs) as reversible electrochemical energy storage (EES) devices. Usually, LiMPO4 can be synthesized via solid phase thermal (SPT) route, which is considered as a crucial process for improving the crystallinity of LiMPO4. However, in the conventional SPT process, e.g., common calcination, energy is generally transferred through heat convection, heat conduction and heat radiation from the surfaces to inners, which entail prolonged exposure to high calcination temperature (e.g. 700°C for 12h). Different from the heat treatment route of calcinaiton, microwave irradiation can provide “inert and instant heating” of LiMPO4 precursors and synthesize even crystallite LiMPO4 cathode materials. This microwave-assisted SPT (MW-SPT) method is not only energy- and time-saving (e.g., 700W, 4min), but also exhibits superiority in optimizing physical characters, improving Li-ion diffusion kinetics and enhancing high rate performance. Furthermore, the microwave-assisted liquid phase thermal (MW-LPT) method has been also employed to prepare LiMPO4 cathode materials. Recently, both MW-SPT and MW-LPT routes have led to increased interest in the development of LiMPO4 cathode materials and processing capabilities to enable high electrochemical performance. In this review, we focus on the LiMPO4 cathode materials synthesized by microwave irradiation assisted synthesis (MIAS) route, which conclude mainly two parts, MW-SPT and MW-LPT routes. The major goal is to highlight the reaction mechanism and current developments of LiMPO4 synthesized via MW-SPT and MW-LPT methods. The structural, morphological and electrochemical performance of LiMPO4 cathode materials prepared by MIAS has also been discussed. [Copyright &y& Elsevier]

Metal–organic frameworks (MOFs)-derived materials with a large specific surface area and rich pore structures are favorable for catalytic performance. In this work, MOFs are successfully prepared. Through pyrolysis of MOFs under nitrogen gas, zinc-based catalysts with different active sites for acetylene acetoxylation are obtained. The influence of the oxygen atom, nitrogen atom, and coexistence of oxygen and nitrogen atoms on the structure and catalytic performance of MOFs-derived catalysts was investigated. According to the results, the catalysts with different catalytic activity are Zn-O-C (33%), Zn-O/N-C (27%), and Zn-N-C (12%). From the measurements of X-ray photoelectron spectroscopy (XPS), it can be confirmed that the formation of different active sites affects the electron cloud density of zinc. The electron cloud density of zinc affects the ability to attract CH3COOH, which makes catalysts different in terms of catalytic activity. [ABSTRACT FROM AUTHOR]