Study On The Removal Of NO_x Flue Gas By Microwave With Coal-based Carbon

Nitric oxide,one of the main air contaminants,is the main reason for the generation of haze,photochemical smog and acid rain.It causes serious damage to human health and ecological environment.The emissions of nitrogen oxides?NO_x?in China mainly come from the thermal power,cement,iron and steel?including coke industry?and other industries.Consideration of the currently flue-gas denitration technology of the temperature,the cost and the large investment.In order to the requirements of the standards of coke industry,a series of experiments about the NO_x removal using coal-based carbon?self-made?,activated coal-based carbon and Fe-based catalysts coal-based carbon under irradiation of microwave have been conducted,and the main contents are as follows:?1?The performance of characterization and mechanism for coal-based carbon of denitration was studied,then coal-based carbon B for the denitration reducing agent in the experiment.The effect of irradiation power of microwave,residence time,the concentration of NO and O2 on NO_x removal efficiency have been investigated.The results showed that microwave power 250w?402.8o C?,NO in flue-gas 268mg/m3,residence time 2.5s,content of O2 5% and gas flow 1000 m L/min,the denitration efficiency of NO can reach 84.85%.The X-Ray diffraction?XRD?,infrared spectroscopy?FT-IR?,scanning electron microscopy?SEM?and other characterization revealed that the coal based carbon B was an excellent de-NO_x carbon material.?2?The activation of coal-based carbon by acid,alkali and basic salt indicated that coal-based carbon activated by acid had negative denitration efficiency,while the alkali and salt activation was beneficial to coal-based carbon denitration.Especially,NO removal efficiency activated by Na OH solution?5%,wt %?was as high as 97.33%at power of 250w?402.8o C?.The results of BET,FT-IR and SEM analysis showed that the denitration efficiency of coal-based activated carbon may be highly related to the acid-base functional groups on the surface,but it was a little related to specific surface area.?3?Fe₂O₃ was loaded on the coal-based carbon by co-precipitation and oxidation precipitation method.The XRD,SEM and EDS characterization indicated that the coal-based carbon was successfully loaded with Fe₂O₃ by the two methods.Gcoal-based carbon and Y-coal-based carbon were performed 83.10% and 80.60%denitration efficiency under the microwave power of 150W?269.2o C?,respectively.The coal-based carbon was loaded with Fe₂O₃ catalyst behaved excellently denitration performance at low temperatures.