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The increase of solid wastes exerted great pressure on the environment and even damaged human health. Given this, the resource utilization of solid wastes became an inevitable trend of the industrial development. However, many researchers recognized that solid wastes with the component of Fe 2 O 3 , SiO 2 , Al 2 O 3 , TiO 2 , etc., could be utilized as the low-cost materials for preparing NH 3 -SCR catalysts, which could solve both the accumulation of solid wastes and the emission of NO x in industrial processes. Herein, some typical solid wastes, such as blast furnace slag (BFS), red mud (RM), coal fly ash (CFA), Fenton sludge (FS), etc., were extensively studied for their potential in NH 3 -SCR catalysts. Although the presence of some harmful components in solid wastes led to catalysts deactivation, they could still be excellent supports applied on NH 3 -SCR catalysts after proper pretreatment. In fact, these catalyst supports derived from solid wastes provided larger specific surface areas, thereby enhancing the NH 3 adsorption and redox capacity and facilitating the active ingredients loaded uniformly. Meanwhile, some useful impurities in solid wastes might also facilitate the NH 3 -SCR performance, achieving denitrification efficiency comparable to other catalysts made from costly materials. Moreover, most of these NH 3 -SCR catalysts performed significant SO 2 and/or H 2 O tolerance via metal oxides-doping, which would expand their potential for practical application in industry. Finally, the prospects for the application of solid wastes in NH 3 -SCR catalysts were also proposed. [Display omitted] • The preparation of SCR catalysts from solid wastes was reviewed. • The concept of treating waste gases with solid wastes was emphasized. • Mechanisms of removing NO x with solid waste catalysts were revealed. • The develop direction of solid waste catalysts was pointed out. [ABSTRACT FROM AUTHOR]

CO-SCR was considered as one of the most optimum technologies for synergistic removal of nitrogen oxides and carbon monoxide from flue gas. CuCe catalyst showed excellent NO x and CO catalytic activity in the range of 250–500 °C because of its unique physicochemical property. Herein, the mechanism of CuCe catalyst in the CO-SCR reaction at different temperature was studied via in situ DRIFTS characterization. The result indicated that the adsorbed CO species could react with gaseous NO molecules over CuCe catalyst at 150 ºC, implying that the E-R mechanism was obeyed at lower temperature. Moreover, the nitrate/nitrite species and adsorbed CO species could react with each other on the surface of CuCe catalyst at 350 ºC, indicating that the L-H mechanism was followed in the CO-SCR reaction at higher temperature. This work proposed the reaction mechanism of CuCe catalyst at different temperature for NO reduction by CO, which could provide a theoretical direction for the optimization of CuCe catalyst and promote its application in industrial production. [Display omitted] • CuCe catalyst exhibited outstanding catalytic performance for NO and CO. • CuCe catalyst had highest ratio of Cu+ and excellent redox capacity. • E-R mechanism was obeyed at 150 °C, while both E-R and L-H at 350 °C. • Mechanism model of CuCe catalyst for CO-SCR reaction was proposed. [ABSTRACT FROM AUTHOR]

The purification of gaseous pollutants, especially for nitrogen oxides, from the combustion of fossil fuels has become a concern matter at present. Selective catalytic reduction (SCR) technology is proved an effective method to remove nitrogen oxides. The performance of catalysts, such as the improvement of anti-poisoning ability and low-temperature catalytic efficiency, become the main direction of current extensive research. Carbonaceous materials were widely applied in low-temperature catalysts for removal of NO x due to their various structures and rich surface functional groups, and had potential to expand the function to remove multipollutant. Herein, different carbonaceous materials, activated methods and carbon-based NH 3 -SCR catalysts were concluded, and the corresponding reaction mechanisms were discussed. In addition, the removal of double or three contamination components with carbon-based catalysts were also summarized and discussed. Finally, further development directions for carbonaceous material in pollutants control were proposed. [Display omitted] • NO x removal with carbonaceous materials was concluded. • Various carbon-based catalysts in recent years were summarized. • The effect and mechanism on NO x removal was elucidated. • Multiple pollutants removal by carbon-based material is proposed. [ABSTRACT FROM AUTHOR]

The study of SCR catalysts for nitrogen oxides reduction with NH 3 had recently attracted much attention. As a typical heavy metal element, Pb was prone to seriously damage the denitrification performance of SCR catalysts in flue-gas environment. This work systematically reviewed the mechanisms of Pb poisoning and anti-deactivation measures reported these years for SCR catalysts. The mechanisms of Pb poisoning were summarized from both physical and chemical aspects, including the specific surface area, redox ability and surface acidity of the catalysts, and the corresponding reaction paths of the catalysts were also considered during the SCR process. In the meantime, this paper reviewed the anti-deactivation mechanisms and measures currently used to solve the problem of lead poisoning for SCR catalysts. The main methods included adding active substances to improve the redox ability and surface acidity of the catalysts, using ions or anti-poisoning sites to preferentially bind to Pb species, or using the structural characteristics of the carriers to prevent Pb from contacting with active substances. The concrete measures included the modification of catalysts with metal oxides and solid super acids, the change of carriers' structure, and the dual effect of carriers and active materials. Finally, a prospect of lead poisoning for further research on SCR catalysts was proposed. [Display omitted] • Physical and chemical mechanisms of Pb poisoning on SCR catalyst were reviewed. • Anti-inactivation mechanisms for SCR catalyst in the presence of Pb were clarified. • Recent advances in anti-Pb measures of SCR catalysts were summarized. • Challenges for Pb poisoning catalyst in industrial application were proposed. [ABSTRACT FROM AUTHOR]