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Abstract Three CuO-ZnO-ZrO 2 -M x O y (CZZM, M = Cr, Mo and W) mixed oxides were prepared by a co-precipitation method and tested as catalysts for methanol synthesis from CO 2 hydrogenation. The catalysts were characterized by XRD, N 2 adsorption/desorption, XPS, reactive N 2 O adsorption, H 2 -TPR, and CO 2 -TPD techniques. The results indicated that the methanol selectivity and yield of the CuO-ZnO-ZrO 2 catalyst noticeably increased by the additions of MoO 3 and WO 3 , but slightly decreased by Cr 2 O 3 doping. Combining with the characterization results, the difference in methanol yield over the three catalysts can be attributed to the differences in their BET specific surface areas (S BET) and adsorption capacities for CO 2 , while the methanol selectivity is closely correlated to the ratio of surface contents of Zn to Cu, as well as the fraction of strong basic sites in the total basic sites of the investigated catalysts. Graphical abstract Image 1 Highlights • CuZnZrM (M = Cr/Mo/W) mixed oxides were used for methanol synthesis from CO 2 and H 2. • The CuO-ZnO-ZrO 2 -WO 3 catalyst shows the highest activity and methanol selectivity. • Methanol yield is related to the S BET and CO 2 adsorption capacity of the catalyst. • Methanol selectivity is closely related to the surface composition and basicity. [ABSTRACT FROM AUTHOR]

A series of CuO-ZnO-Al 2 O 3 -Li 2 O catalysts with various Al 2 O 3 /Li 2 O mass ratios were prepared by co-precipitation method and characterized by several techniques such as XRD, N 2 adsorption, SEM/EDX, reactive N 2 O adsorption, XPS/XAES, H 2 -TPR, H 2 -TPD, and CO-TPD. The results revealed that the specific surface area ( S BET ), dispersity of Cu species, metallic Cu surface area ( S Cu ) and adsorption capacity for reactants (H 2 and CO) were increased by the addition of suitable amount of Li 2 O to the CuO-ZnO-Al 2 O 3 catalyst, thus enhancing the catalytic activity of the hybrid catalyst composed of CuO-ZnO-Al 2 O 3 and HZSM-5 for the direct synthesis of dimethyl ether from biomass-derived gas. Furthermore, the addition of Li 2 O significantly improved the stability of CuO-ZnO-Al 2 O 3 catalyst due to the effective inhibition of the crystallization of Cu and ZnO. [ABSTRACT FROM AUTHOR]

A series of fluorinated nano-HZSM-5 zeolite catalysts were prepared by impregnating with NH 4 F solutions of various concentrations and applied to the selective conversion of bio-ethanol to propene at 500 °C, atmospheric pressure, and WHSV of 10 h − 1 . The characterizations by XRD, TEM, N 2 adsorption, ICP-OES, EDX, 27 Al MAS NMR, NH 3 -TPD, Py-IR, and TG techniques revealed that fluoride treatment had a major effect on the channel structure together with the acidic properties. The newly formed mesopores increased the coke tolerance capacity and reduced the probability of coke formation by facilitating mass transfer, and the weakened acidity suppressed the formation of coke. Hence, fluorine modification with suitable content (20 wt%) significantly enhanced the selectivity of propene as well as the catalytic stability. In addition to coke, elimination of aluminum in the zeolite framework was also an important reason for the deactivation of fluorinated nano-HZSM-5 zeolite catalyst. [ABSTRACT FROM AUTHOR]

• CuO-Ce x Zr 1-x O y are prepared via a facile surfactant-assisted grinding method. • CuO-Ce 0.7 Zr 0.3 O y exhibits the highest activity and moisture resistance. • Activity is related to contents of highly dispersed CuO and oxygen vacancies. • CO oxidation catalyzed by CuO-Ce x Zr 1-x O y mainly follows the L-H mechanism. • CuO-Ce 0.7 Zr 0.3 O y exhibits excellent stability and adaptability to space velocity. A series of CuO-Ce x Zr 1-x O y mixed oxides with different Ce contents were prepared via a facile surfactant-assisted grinding method, and their catalytic activity for CO oxidation under dry or moist atmosphere were investigated. The results indicate that the catalyst with a Ce content (x) of 0.7 in Ce x Zr 1-x O y (CuCe 0.7 Zr 0.3) exhibited the best activity under both dry and moist atmospheres, with the temperatures corresponding to CO conversion of 90 % (T 90) at a space velocity of 18000 mL/(g cat · h) being 90 and 120 °C, respectively. Combing with the physicochemical properties of the catalysts obtained by multiple characterization techniques such as ICP-OES, XRD, Raman, N 2 sorption, XPS, in situ DRIFTs, H 2 -TPR, O 2 -TPD and CO-TPD, the high activity of the CuCe 0.7 Zr 0.3 catalyst can be mainly attributed to the existence of large amounts of highly dispersed CuO x species and oxygen defect sites. [ABSTRACT FROM AUTHOR]