| Air pollution cause one of the main types of environmental pollution right now. In the atmospheric pollution, air polluted material is delegated with sulfur oxides mainly represented by SO2and nitrogen oxides mainly represented by NO. In our country, the air polluted material mainly comes from burning coal. So the control of these sulfur oxides and nitrogen oxides from the burning of the coal is the priority of our country’s environmental protection work. In this situation, a lot of desulfurization and denitration methods have been developed. In these desulfurization and denitration methods, the dry desulfurization and denitration method is widely welcomed by the advantages in which does not produce liquid pollutants, equipment is very simple and it can remove the SO2and NO at the same time. In the dry desulfurization and denitration method, methane as a reducing gas which has its own unique advantage. Methane is a relatively good reluctant which has widely sources, no pollution, no corrosion resistance. Because semi-coke has some advantages which is comparatively rich surface properties and cheaper price, strong mechanical strength, so it is suitable for as a carrier of the methane gas desulfurization and denitration.In order to discuss factors of the influence about desulfurization and denitration of methane, this paper presents the systematic study of catalyst which used as a carrier and on which loaded on various metal oxides. in this semi-coke catalyst, we study the performance of desulfurization and denitration which used methane as resistant gas, and pyrolysis of methane, desulfurization and denitration active, the mechanism of carbon deposit were been studied.The conclusions of these articles as follows:(1) Raw semi-coke itself may cause the CH4decomposition, in various of activation methods, the alkali activation can improve the cracking of the methane greatly.(2) In the semi-coke catalyst carried a certain concentration can low the temperature of simultaneous desulfurization and denitrification reaction effectively. The experiment shows that1.5%PdO is the most effectively in all concentration of PdO to the methane creaking; What’s more, carries1%V2O5is very in favor of increasing desulfurization.(3) In the reaction condition, space velocity can affect the activity of simultaneous desulfurization and denitrification. In the CH4desulfurization and denitrification,1200h-1is the best space velocity; when O2content is4%, desulfurization and denitrification rate has reached the best balance point, at this point; it is conductive to the rise of activity. What’s more, with the rise of content of water vapor, the activity of denitrification is drop sharply, at the same time,the activity of desulfurization is maintaining stability, when the content of water vapor is4%, the activity is the best.(4) When the input of CH4is1000ppm, the concentration of CH4/NO is1.2, the activity is the best.(5) From the experiment we know, denitration is conducive to desulfurization, however, desulfurization is prejudice to denitration.(6) A certain of CH4creaking rate is very important for ensuring the high activity of desulfurization and denitration, the best CH4creaking rate is40%-50%.(7) Carbon deposition has a big impact on the activity of desulfurization and denitration. CeO2have anti-carbon deposition, when add to2%CeO2on the semi-coke catalyst, the rate of carbon deposition is drop obviously, at the same time, the activity of desulfurization and denitration is very good.(8) From the life experiment of semi-coke catalyst, the life of semi-coke catalyst is4circulations. After4circulations later, the activity is drop sharply because of the amount of carbon deposition is heavy.(9) In the regenerate experiment of semi-catalyst, when regenerate temperature is about420℃, the regenerate rate is the best, regenerate time is about100min, regenerate time is3times; H2come from the cracking of methane is help to the regeneration of catalyst, when the cracking rate is about35%; the regenerate rate is very high. What’s more, when the cracking rate of methane is stably, the increase of concentration of methane does not improve the regenerate rate. |
