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removal of co from reformed fuels by selective methanation over Ni-B-Zr-O_δ catalysts

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Journal of Natural Gas Chemistry 2009年第2期18卷 173-178页

作者： Qihai Liu Xinfa Dong Yibing Song Weiming Lin School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 Guangdong China college of Science Shantou University Shantou 515063 Guangdong China

The Ni-B-Oδ and Ni-B-Zr-Oδ catalysts were prepared by the method of chemical reduction, and the deep removal of co by selective methanation from the reformed fuels was performed over the as-prepared catalysts. The results showed that zirconium strongly influenced the activity and selectivity of the Ni-B-Zr-Oδ catalysts. Over the Ni-B-Oδ catalyst, the highest co conversion obtained was only 24.32% under the experi-mental conditions studied. However, over the Ni-B-Zr-Oδ catalysts, the co methanation conversion was higher than 90% when the temperature was increased to 220℃. Additionally, it was found that the Ni/B mole ratio also affected the performance of the Ni-B-Zr-Oδ catalysts. With the increase of the Ni/B mole ratio from 1.8 to 2.2, the co methanation activity of the catalyst was improved. But when the Ni/B mole ratio was higher than 2.2, the performance of the catalyst for co selective methanation decreased instead. Among all the catalysts, the Ni29B13Zr58Oδ catalyst investigated here exhibited the highest catalytic performance for the co selective methanation, which was capable of reducing the co outlet concentration to less than 40 ppm from the feed gases stream in the temperature range of 230-250℃, while the co2 conversion was kept below 8% all along. Characterization of the Ni-B-Oδ and Ni-B-Zr-Oδ catalysts was provided by XRD, SEM, DSC, and XPS.

关键词： selective methanation co removal Ni-B-Zr-Oδ catalyst reformed fuels

Selective Oxidation of co in Excess H_2 over Ru/Al_2O_3 Catalysts Modified with Metal Oxide

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Journal of Natural Gas Chemistry 2007年第4期16卷 409-414页

作者： Xirong Chen Hanbo Zou Shengzhou Chen Xinfa Dong Weiming Lin School of Chemical and Energy Engineering South China University of Technology Guangzhou 510651 Guangdong China School of Chemistry and Chemical Engineering Guangzhou University Guangzhou 510006 Guangdong China

The Ru/Al2O3 catalysts modified with metal oxide （K20 and La2O3） were prepared v/a incipient wetness impregnation method from ***2O 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-K20/Al2O3 and Ru-La2O3/Al2O3 were lowered approximately 30℃ compared with pure Ru/Al2O3, and the activity temperature range was widened. The conversion of co on Ru-K20/Al2O3 and Ru-La2O3/Al2O3 was above 99% at 140-160℃, suitable to remove co in a hydrogen-rich gas and the selectivity of Ru-La2O3/Al2O3 was higher than that of Ru-K2O/Al2O3in the active temperature range. Slight methanation reaction was detected at 220℃ and above.

关键词： hydrogen-rich gas ruthenium based catalysts co removal selective oxidation metal oxide

Selective catalytic methanation of co in hydrogen-rich gases over Ni/ZrO_2 catalyst

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Journal of Natural Gas Chemistry 2008年第3期17卷 268-272页

作者： Qihai Liu Xinfa Dong Xinman Mo Weiming Lin School of Chemistry and Chemical Engineering South China University of Technology Guangzhou 510640 Guangdong China

Ni/ZrO2 catalysts were prepared by the incipient-wetness impregnation method and were investigated in activity and selectivity for the selective catalytic methanation of co in hydrogen-rich gases with more than 20 vol% co2. The result showed that Ni loadings significantly influenced the performance of Ni/ZrO2 catalyst. The 1.6 wt% Ni loading catalyst exhibited the highest catalytic activity among all the catalysts in the selective methanation of co in hydrogen-rich gas. The outlet concentration of co was less than 20 ppm with the hydrogen consumption below 7%, at a gas-hourly-space velocity as high as 10000 h-1 and a temperature range of 260 °C to 280 °C. The X-ray diffraction （XRD） and temperature programmed reduction （TPR） measurements showed that NiO was dispersed thoroughly on the surface of ZrO2 support if Ni loading was under 1.6 wt%. When Ni loading was increased to 3 wt% or above, the free bulk NiO species began to assemble, which was not favorable to increase the selectivity of the catalyst.

关键词： selective methanation co removal Ni/ZrO2 catalyst hydrogen-rich gases fuel cell

Performance of Ni/Nano-ZrO_2 Catalysts for co Preferential Methanation

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Chinese Journal of Chemical Engineering 2014年第2期22卷 131-135页

作者：刘其海董新法刘自力 School of Chemistry and Chemical Engineering ZhongKai University of Agriculture and Engineering School of Chemistry and Chemical Engineering South China University of Technology School of Chemistry and Chemical Engineering Guangzhou University

Large surface areas nano-scale zirconia was prepared by the self-assembly route and was employed as support in nickel catalysts for the co selective methanation. The effects of Ni loading and the catalyst calcination temperature on the performance of the catalyst for co selective methanation reaction were investigated. The cata- lysts were characterized by Brunauer-Emmett-Teller （BET）, transmission electron microscope （TEM）, X-ray dif- fraction （XRD） and temperature-programmed reduction （TPR）. The results showed that the as-synthesized Ni/nano-ZrO2 catalysts presented high activity for co methanation due to the interaction between Ni active particle and nano zir- conia support. The selectivity for the co methanation influenced significantly by the particle size of the active Ni species. The exorbitant calcination resulted in the conglomeration of dispersive Ni particles and led to the decrease of co methanation selectivity. Among the catalysts studied, the 7.5% （by mass） Ni/ZrO2 catalyst calcinated at 500℃ was the most effective for the co selective methanation. It can preferentially catalyze the co methanation with a higher 99% conversion in the co/co2 competitive methanation system over the temperature range of 260-280℃, while keeping the co2 conversion relatively low.

关键词： selective co methanation co removal nano zirconia Ni catalysts

An air cleaner for road tunnels

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Journal of Chongqing University 2003年第1期2卷 13-16页

作者：雷玉勇 Sichuan University of Science and Technology Chengdu 610039 P.R. China

an air cleaner employing pulse induced plasma chemical process to remove dust and carbon monoxide (co) in road tunnels is presented, which is composed of mainly a precipitator, a reactor, a flow control system, a power supply and a measurement system. Its performances are studied in simulated air conditions. It is found that the rate of dust removal is dependent on the voltage of the pulse power, the distance between the two dust collecting plates of the electrostatic precipitator, the effective length of the precipitator and the air flow rate in the precipitator, and that of co removal is affected by the voltage and frequency of the super pulse power, the air flow rate in the reactor and the relative humidity of air. Applying such an cleaner of a proper design to the treatment of polluted air at a flow rate of 7 m/s can achieve the rate of dust removal up to 93 % and that of co removal up to 72.6 %, which efficiently controls the concentrations of co and dust under allowable limits. It is implied that the proposed air cleaner is a potential solution to air control in road tunnels, and is prominent for its performances and saving the huge cost of longitudinal ventilation tunnel or vertical vent and ventilation facilities.

关键词： air pollution air pollution control dust removal road tunnel co removal