Study On The Mechanism Of NO Removal By Plasma-Adsorption Catalytic Process

In the past ten decade,the air pollution is becoming more and more serious.Nitrogen oxides?NOX?are one of the primary pollutants in the atmosphere because they not only cause serious environmental problems including acid rain and photochemical smog but also are harmful to human health.Hence,developing strategies to reduce the NO emission has been a problem of paramount concern.Compared with other technologies,the low temperature plasma?NTP?method has many advantages,such as small footprint,high removal rate and removal of various pollutants,the non-thermal plasma?NTP?has many advantages,such as high removal efficiency,small footprint and simultaneous removal of various pollutants.Therefore,it is feasible to remove NO by the NTP technology.An integrated technology,the non-thermal plasma?NTP?combined with bamboo charcoal?BC?adsorption catalytic,was used for the removal of NO.?1?The removal of NO was studied by using the BC system alone,plasma treatment system alone and the plasma/BC treatment system,respectively.The datas show the removal rate of NO is the best in the the synergistic effect.?2?In the BC system alone,the BC removal of NO depends on the physical and chemical adsorption of the BC.At the beginning of the experiment,the physical adsorption of BC is dominant.With the reaction,the chemical adsorption is dominant.Both in the plasma system alone and the plasma/BC treatment system,the plasma removal of NO is mainly achieved by the reduction reaction that NO is decomposed into N2 and O₂?It was found that the BC can extend gas residence time and act as a scavenger of O₂.?3?In the plasma/BC system,the effects of applied input voltage,O₂ content and SO₂ concentration on the NO removal were investigated systematically.The NO removal rate is increased trend with increasing input voltage,reaching the maXimum at 80 V,and then decreased at higher applied voltage.The presence of O₂ and SO₂ remarkably inhibited the removal of NO.When the input voltage is 80 V and,the maximum removal efficiency of NO?4?can reach 74.0 % in the synthetic gas?the content of O₂ is 8%?.?5?The adsorbents were characterized by SEM,XRD,N2 adsorption-desorption and XPS to analyze the physical and chemical properties of the BC.The exernal surface of the reacted BC had a large number of small cavities.This is because the BC material was etched by plasma charge during experiment,which increased the number of pores of the treated BC,supported by BET results?0.17 cm3/g?.The BC is amorphous carbon structure.After the reaction,the content of graphit carbon was reduced,however,the content of C=O and-COO groups were increased,which was consistent with the mechanism of NO removal by the synergistic effect of NTP and BC adsorption catalysis process.