| In recent years, cleanning coke oven gas conversion has stirred attention from both environmental protection and energy-saving emission reduction. At the same time, because of lack of nature gas, conversion coke oven gas to SNG (substitude nature gas) is becoming an important technology. It is of great significance to solve our future natural gas demand,energy security,energy saving and emission reduction. Many studies have reported Ru or Ni catalyst research for CO and CO2 methanation for purifying fuel cell or ammonia synthesis feed gas, but very few results for ruthenium-based catalyst for high CO concentrations about coke oven gas to natural gas. Therefore, this dissertation it has been highlighted that the tests of the methanation performance of Ru catalysts supported on oxides in coke oven gas.1,The effect of supports on the methanation of CO of Ru catalysts has been investigated. The order of activity is shown as follows:Ru/Al2O3> Ru/MgO> Ru/SiO2.2,The methanation performances of a series of y-Al2O3 supported transition metal catalysts have been explored by the employment of activity test. The order of catalytic activity is shown as follows:Ru/Al2O3> Co/Al2O3> Ni/Al2O3. Among the catalysts Ru/Al2O3 catalyst has the highest activity for the methanation of CO with the least activation energy.3,The influences of preparation method (wet impregnation and ultrasonic impregnation) and ultrasonic impregnation time and frequence, Ru loadings of Ru/Al2O3 on the activity of catalysts have been investigated. The results showed that when Ru loadings 0.5 wt%, compared with the catalyst prepared by impregnation method, the catalyst prepared by ultrasonic impregnation method performed higher activity and also save catalyst impregnation time, the right impregnation time was 20 min and ultrasonic frequence 40 kHz. As the Ru content increases, CO conversion not change significantly and seems to attain a plateau, while methane selectivity decreased gradually, CO2 selectivity increased gradually.2% wt% Ru is appropriate catalyst metal loading, the conversion of CO and CH4 selectivity are 98.33% and 83.29%, respectively.4,The influences of preparation condition (calcined temperature and reduction temperature),addition of promoters and effect of Cl- on activity of Ru/Al2O3 catalyst have been investigated. A suitable catalyst calcination temperature was 500℃, reduction temperature was 400℃. The addition of promoters of VIII metal and non-VIII metal into the single Ru metal catalyst will result in more or less decrease of Catalytic activity. Addition, filtrating the sample after RuCl3 was impregnated, It can effectively remove Cl- and improve catalyst activity, in particular, the effect of washing with dilute ammonia and deionized water is evident.5,The influences of space velocity,ratio of CO and H2,reaction temperature on activity of Ru/Al2O3 catalyst have been investigated and then examined the catalyst thermal stability and sulfer resistance. The optimal reaction conditions are space velocity 3000 h-1; with ratio of CO and H2 increased, CO conversion and CH4 selectivity increaseed; as the reaction temperature increasing, CO conversion and CH4 selectivity firstly increased and then a little decreased, studies show that 300-400℃for the more appropriate reaction temperature. The study also found that the catalyst has good activity after 26 h, the catalyst sulfer-resistant amount limits was 1.72μL.g-1.
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