燃煤电厂排放的烟气中含有大量的氮氧化物，不仅对生态环境造成了巨大的危害，也是产生雾霾的主要原因之一。氮氧化物中的主要成分为NO，NO不溶于水的特性使其难以在传统脱硫塔中进行脱除。为经济有效的脱除燃煤烟气中的氮氧化物，采用氧化吸收法进行脱硝研究。通过对比不同氧化剂的氧化性能，选取ClO2为氧化剂，将其在140 ℃的条件下进行气化，转变为类气相氧化剂。将烟气中NO预氧化成易溶于水的NO2，再结合饱和氢氧化钙溶液吸收氧化产物进行燃煤烟气脱硝研究。通过电子顺磁共振检测(ESR)以及·OH抑制剂添加实验说明类气相ClO2在氧化过程中产生了·OH等强氧化性自由基，极大地促进了对NO的氧化。实验结果表明，脱硝效率随物质的量比(ClO2/NO)的增加而增加，当物质的量比(ClO2/NO)大于0.84后，脱除效率增加缓慢;在110~170 ℃内，温度对类气相ClO2脱除NO的影响较小;酸性条件有利于NO的脱除效率的增加，但总体影响较小，当烟气中SO2与NO共同存在时，类气相ClO2优先氧化烟气中的NO。最佳反应条件为:物质的量比(ClO2/NO)=0.84，反应温度为140 ℃，溶液pH=3左右，此时NO的氧化脱除效率可以达到92.5%。采用离子色谱对氧化产物分析，指出NO的主要氧化产物为NO-3并提出类气相ClO2对烟气中NO的氧化脱除机理，表明类气相ClO2结合碱液氧化吸收具有良好的工业应用前景。

The flue gas emitted by coal-fired power plants contains a large amount of nitrogen oxides,which not only causes great harm to the ecological environment,but also is one of the main causes of smog. However,the main compo- nent of nitrogen oxides is NO,and the insoluble nature of NO makes it difficult to remove in a conventional desulfuriza- tion tower. In order to economically and effectively remove nitrogen oxides from coal-fired flue gas,the oxidative ab- sorption method was used for denitration research. By comparing the oxidation performance of different oxidants,ClO2 was selected as the oxidant,and it was gasified at 140 ℃ to be converted into a gas-phase-like oxidant. The NO in the flue gas was pre-oxidized into NO2 which is easily soluble in water,and then combined with the saturated calcium hy- droxide solution to absorb the oxidation product for the denitration of coal-fired flue gas. Electron paramagnetic reso- nance (ESR) and ·OH inhibitor addition experiments showed that the gas phase ClO2 generated strong oxidizing rad- icals such as ·OH during the oxidation process,which greatly promoted the oxidation of NO. The experimental results showed that the denitration efficiency increases with the increase of molar ratio ( ClO2 / NO). When the molar ratio (ClO2 / NO) was more than 0. 84,the removal efficiency increased slowly. In the range of 110 -170 ℃ ,the effect of temperature on NO removal was weak. The acidic condition was beneficial to the increase of NO removal,but the over- all effect was small. When SO2 and NO coexisted in the flue gas,the gas phase ClO2 preferentially oxidized NO in the flue gas. The optimum reaction conditions are:molar ratio (ClO2 / NO)= 0. 84,reaction temperature of 140 ℃ ,pH = 3, and the oxidative removal efficiency of NO can reach 92. 5% . The analysis of oxidation products by ion chromatogra- phy indicated that the main oxidation product of NO was NO- and proposed the mechanism of oxidative removal of NO in flue gas by gas-phase ClO2 . It indicated that the gas phase ClO2 combined with lye oxidation absorption has good in- dustrial application prospects.