| Carbon dioxide (CO2) is not only the main reason leading to greenhouse effec but also an important carbon resource. It is urgent to recover CO2 and/or make good use of it or bury it underground, which are effective routes to slow down CO2 release. The 70% fuel in China depends on coal, which means that the future study will focus on CO2 recovery from a flue gas produced by coal combustion. It is difficulty to remove NOX especially nitric oxide (NO) contained from a flue gas to produce high purity or even food-grade CO2·The best method for deep removal of NO is adsorption. The purpose of the thesis is to explore NO adsorbent, which can be recycled, for deep removal of low concentration NO from CO2 both in the presence and in the absence of O2, and provide some references for the industrialization of NO adsorbent.HZSM-5 and ZrO2 are the best adsorbent carriers which can remove 150～200 ppm NO to 0.1 ppm from N2·NH3-TPD and pyridine adsorption characterizations demonstrate that the adsorption ablitiy of carriers for NO denpends on their Lewis acidity.4wt% Fe, Mn, Ni, Co, Cu, Ce oxides modified HZSM-5(nSiO2/nAl2O3=25) can also remove NO to 0.1 ppm, and Ni/HZSM-5(25) displays the best cost performance with a Ni loading amount of 4wt%, and its breakthrough capacity for NO is 6 times higher than HZSM-5(25) at the same condition. The utilization ratio of Ni ions on a carrier for NO adsorption is proportional to the pore size of zeolites carriers. Low temperature and/or O2 introduction are beneficial for improving the NO capacity of Ni/HZSM-5(25), but CO2 shows a converse effect. The adsorbent can be regenerated using N2 blowing at 400 -500℃.NO can be deeply removed to less than 0.1 ppm from a CO2 stream by Ni, Co, Cu, Mn/HZSM-5(25). The order of their adsorption capacity in the absence and presence of O2 is Co> Ni> Cu> Mn and Co> Cu> Mn> Ni respectively. They demonstrate a better adsorption performance than Fe-Mn mixed oxides, which were reported as the best NO oxidative adsorbents. In-situ FT-IR characterization results proved that NO and CO2 can more weakly adsorbed on Mn/HZSM-5(25) than Ni/HZSM-5(25), and NOX can be easily stored onto Mn/HZSM-5(25). NOx desorption temperatures of the above four adsorbents are all near 400℃; The desorption temperature and the NO ratio of the desorbed NOx for Co and Cu/HZSM-5(25) is higher than Mn/HZSM-5(25), which increases difficulty when dealing with the desorbed gases in industry. Mn/HZSM-5(25) will be the potential industrial adsorbent considering its low regeneration temperature and cheap price. The relationship between the oxidative adsorption ability to NO and the configuration /surface properties of Mn modified HZSM-5(25), which were prepared by ion-exchange, incipient wetness impregnation and precipitation methods and characterized using XRF, nitrogen adsorption (BET), XRD, FT-IR, SEM, UV-vis, UV-Raman, XPS, H2-TPR and NOx-TPD technologies. It was found that Mn/HZSM-5(25) prepared by impregnation method showed the best performance, and most of the manganese species distributed on the internal surface of ZSM-5. The active component Mn3O4 showed a better oxidative adsorption performance than Mn2O3 and Mn2+. It is the synergetic effect of Mn3O4 and ZSM-5 aperture that lead to effective NO oxidation and adsorption on Mn/HZSM-5(25). The activation temperature of Mn/HZSM-5(25) should be above 300℃, and 500℃is the best. The NO oxidative adsorption process can be accelerated by reducing temperature and increasing O2 concentration, but badly affected by diffusion, water and sulfer pre-adsorpiton; The adsorbent can be regenerated at 500℃using dry air with a regeneration rate as high as 75%.
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