Sutudy On Adsorption Catalyst Of Synergistic Removal Of Mercury And Nitrogen Oxides Under Low Temperature In Coal-fired Flue Gas

The mercury is a kind of violently poisonous, highly volatile substance and permanent accumulation virulent material in organism and the food chain. Nitrogen oxides are not only one of the major sources of acid rain but also happened photochemical reaction with hydrocarbons in the summer with strong sunlight, generateing photochemical smog. How to control coal-fired oxides of nitrogen and gaseous mercury generated has become the important problems to be solved in our country. In the early research work foundation, we draw lessons from foreign leading technology research. This project proposes to united remove heavy metal Hg and NOx, development of new, cheap, mild reaction condition of transition metal loaded natural mineral as carrier adsorption catalyst, this paper study the synergistic effect to different pollutants in the process of removing, solid surface absorption, adsorption and with chemical reaction mechanism, for implementation pollutants removal by combined process.The experimental results show that:The best condition of synergis tic removal of mercury and nitrogen oxides is that the concentration of both NO and NH3is500ppm.Generally speaking,in the process of r aising the temperature from100℃to350℃,all kinds of modified adsor ption catalysts’s removal rate for nitrogen oxides increases slowly wi th a rising temperature. The removal rate of modified adsorption catal ysts for nitrogen oxides from high to low in turn for:CeO2/bentonite> CuO/bentonite> FeCl3/bentonite, MnO2/vermiculite> CeO2/vermiculit e;MnO2/mordenite> CeO2/mordenite> CuO/mordenite.Among them, CeO2/bentonite, CeO2/vermiculite and CeO2/mordenite may not have the be st activity in low temperature, but they are stable with a wide activit y area.The amount of the carrier is certain, the best temperature of a dsorption catalyst is250℃when the carrier loads MnO2, MnO2shows it’s best activity in low temperature. No matter how is the temperatur e, under the action of all kinds of adsorption catalysts, the conversio n rate of NO decreases little by little as the airspeed increases gradu ally, we screen adsorption catalysts through denitration effect and stab ility, we get CeO2/mordenite and CeO2/bentonite in150℃,MnO2/ver miculite and MnO2/mordenite in250℃,they work well in removing m ercury and nitrogen oxides at the same time. we select severl adsorpti on catalysts they work well in removing mercury and nitrogen oxides at the same time to characterized by BET, fourier transform infrared s pectra(FT-IR),X-ray diffraction powder(XRD),scanning electron microsc ope techniques(SEM) and so on.Introduced some of the basic mathematical models,established kinetic equations,and carried on the fitting to the experiment data,obtained the adsorption equilibrium constant, the theory biggest adsorptive capacity,the heat of adsorption and the adsorption speed equation under the different reaction temperature.The concrete data indict that the temperature100℃, qmax=2.55*10-6k=1.777*105m3/g; at the temperature175℃, qmax=6.0978*10-6, k=1.199*105m3/g; at the temperature200℃, qmax=5.482*10-6, k=1.241*105m3/g.And at the temperature175℃, CeO2/mordenite to Hg0adsorption speed equation shows as follow: q＝qe[1-exp(0.8286t0.386)]。...