Hanbo Zou

Selective Oxidation of CO in Excess H2 over Ru/Al2O3 Catalysts Modified with Metal Oxide

Abstract The Ru/Al2O3 catalysts modified with metal oxide (K2OandLa2O3) were prepared via incipient wetness impregnation method from RuCl3·nH2O mixed with nitrate loading on Al2O3 support. The activity of catalysts was evaluated under simulative conditions for the preferential oxidation of CO (CO-PROX) from the hydrogen-rich gas streams produced by reforming gas, and the performances of catalysts were investigated by XRD and TPR. The results showed that the activity temperature of the modified catalysts Ru-K2O/Al2O3 and Ru-La2O3/Al2O3 were lowered approximately 30 °C compared with pure Ru/Al2O3, and the activity temperature range was widened. The conversion of CO on Ru-K2O/Al2O3 and Ru-La2O3/Al2O3 was above 99% at 140–160 °C, suitable to remove CO in a hydrogen-rich gas and the selectivity of Ru-La2O3/Al2O3 was higher than that of Ru-K2O/Al2O3 in the active temperature range. Slight methanation reaction was detected at 220 °C and above.

Effect of rare earth and other cationic promoters on properties of CoMoNx/CNTs catalysts for ammonia decomposition

Carbon nanotubes (CNTs) supported Co-Mo nitride catalysts were prepared by incipient-wetness impregnation method and temperature-programmed reaction in N2-H2 mixed gases. The effects of cationic promoters (K, Ba, La, Ce and Zr) on the catalytic performance and surface properties were investigated. All samples were characterized by N2 physical adsorption, X-ray diffraction, and temperature-programmed reduction of H2. The results showed that the addition of promoters reduced the crystallite size of Mo2N and Co3Mo3N species and increased their surface area and dispersion. Among the catalysts, the La promoted CoMoNx/CNTs catalyst had the highest ammonia conversion which could reach 97.63% at 600 °C.

Effect of pretreatment methods on the performance of Cu-Zr-Ce-O catalyst for CO selective oxidation

Abstract The Cu-Zr-Ce-O catalysts prepared using the coprecipitation method exhibited better catalytic performance for CO selective oxidation. The Cu-Zr-Ce-O catalysts pretreated with different methods were studied by CO-TPR and XPS techniques. The results showed that the Cu-Zr-Ce-O catalyst pretreated with oxygen exhibited the best catalytic performance and had the widest operating temperature window, with CO conversion above 99% from 160 to 200° C. The O 2 pretreatment caused an enrichment of the oxygen storaged on the Cu active species and promoted the conversion of adsorbed oxygen into surface lattice oxygen. It also improved the amount of Cu + /Cu 2+ ionic pair, and then facilitated the formation of CuO active species on the catalyst for selective CO oxidation.

In Situ Carbon Coated LiNi0.5Mn1.5O4 Cathode Material Prepared by Prepolymer of Melamine Formaldehyde Resin Assisted Method

Carbon coated spinel LiNi0.5Mn1.5O4 were prepared by spray-drying using prepolymer of melamine formaldehyde resin (PMF) as carbon source of carbon coating layer. The PMF carbon coated LiNi0.5Mn1.5O4 was characterized by XRD, SEM, and other electrochemical measurements. The as-prepared lithium nickel manganese oxide has the cubic face-centered spinel structure with a space group of Fd3m. It showed good electrochemical performance as a cathode material for lithium ion battery. After 100 discharge and charge cycles at 0.5 C rate, the specific discharge capacity of carbon coated LiNi0.5Mn1.5O4 was 130 mAh·g−1, and the corresponding capacity retention was 98.8%. The 100th cycle specific discharge capacity at 10 C rate of carbon coated LiNi0.5Mn1.5O4 was 105.4 mAh·g−1, and even the corresponding capacity retention was 95.2%.

Study on the Catalytic Performance of CuO-CeO2 Catalysts Doped with Transition Metal Oxides for Selective CO Oxidation

A series of CuO-CeO2 catalysts doped with transition metal oxides were prepared by co-precipitation method for selective CO oxidation and the effects of the additives on the catalytic performance were examined by H2-TPR, in-situ DRIFTS techniques. The results showed that the main CO adsorption site on CuO-CeO2 series catalysts was Cu+ species. The catalytic activity at lower temperatures was related to the CO desorption. The doping of ZnO improved the catalytic activity evidently and the CO conversion and selectivity of Cu1Zn1Ce9Od could reach 99.9% and 76.4% at 160°C, respectively. ZnO not only stabilized the reduced Cu+ species, but also increased the capacity of CO adsorption.