Cu-ZSM-5 直接催化分解烟气中的 NO 具有潜在的应用前景。 然而，高温的烟气中存在不 同种类的碱金属，碱金属对 Cu-ZSM-5 催化分解 NO 的影响机制尚不清楚。 采用液相浸渍法将碱 金属 Na，K 负载到离子交换法制备的 Cu-ZSM-5 催化剂。 探究了碱金属负载量对新鲜的 Cu- ZSM-5 催化剂直接催化分解 NO 转化率的影响，并采用 XRD，BET，SEM，TEM，XPS，H2 -TPR 和 O2 -TPD 等表征技术手段对其催化剂骨架结构、孔隙规律、铜物种种类、化学吸附氧和活性物种中 氧气的脱附进行分析。 研究结果表明，在最佳反应温度 550 °C 下，Cu-ZSM-5 催化剂催化分解 NO 转化率为 53%。 随着碱金属 Na，K 负载量的提高，Cu-ZSM-5 催化剂直接催化分解 NO 转换率有明 显的抑制作用，且碱金属 K 造成催化剂 NO 转化率降低的幅度明显高于碱金属 Na。 碱金属 K 可以 破坏的 ZSM-5 分子筛内部独特的三维交叉孔道结构，致使催化剂骨架结构坍塌，堵塞孔道，进一步 阻碍了反应物 NO 与活性位点{Cu-O-Cu}2+ 的接触，从而导致 NO 转化率降低。 活性成分{Cu-O- Cu} 2+ 部位可以与碱金属 Na，K 相结合致使催化剂失活，使其转变为新的铜物种 CuO 微粒，且随着 碱金属 Na，K 含量的增加，CuO 数量也逐渐增多，CuO 微粒可以占据催化剂孔道和覆盖在催化剂外 表面，致使催化剂微孔比表面积和微孔孔容降低。 碱金属 Na，K 抑制了催化剂活性成分{Cu-O- Cu}2+与{Cu-□-Cu}2+之间的氧化还原循环，进而阻碍了 NO 催化分解成 N2和 O2。

The direct catalytic decomposition of NO in flue gases by Cu - ZSM - 5 has potential application. However，there are different kinds of alkali metals in high⁃temperature flue gas，and the mechanism of the effect of alkali metals on the catalytic decomposition of NO by the Cu-ZSM-5 is still unclear. In this paper，the alkali metals Na and K were loaded onto the Cu-ZSM-5 catalyst prepared by the ion exchange method using liquid phase impreg⁃ nation. The effect of alkali metal loading on the direct catalytic decomposition of NO conversion of the fresh Cu- ZSM-5 catalyst was investigated and its catalyst skeleton structure，pore pattern，copper species，chemisorbed oxygen and oxygen desorption from the active species were analyzed by means of characterization techniques such as the XRD，BET，SEM，TEM，XPS，H2 -TPR and O2 -TPD. The research results show that the conversion of NO for cata⁃ lytic decomposition over the Cu-ZSM-5 catalyst is 53% at an optimum reaction temperature of 550 °C . With the in⁃ crease of alkali metal Na and K loading，the direct catalytic decomposition NO conversion rate of the Cu-ZSM- 5 catalyst is significantly inhibited，and the alkali metal K causes a significantly higher reduction in the NO conver⁃ sion rate of the catalyst than the alkali metal Na. The unique three⁃dimensional cross⁃pore structure within the ZSM- 5 molecular sieve，which can be disrupted by alkali metal K，causes the catalyst skeleton structure to collapse，bloc⁃ king the pore channels and further preventing the contact of the reactant NO with the active site {Cu-O-Cu}2+， leading to a reduction in the NO conversion. The active component {Cu-O-Cu}2+ site can combine with the alka⁃ li metals Na and K to deactivate the catalyst， transforming it into the new copper species CuO particles. And as the content of the alkali metals Na and K increases，the amount of CuO also gradually increases，and the CuO par⁃ ticles can occupy the catalyst pore channels and cover the outer surface of the catalyst，resulting in a reduction in the specific surface area and pore volume of the catalyst micropores. The alkali metals Na and K inhibit the redox cycle between the catalyst active components { Cu-O-Cu} 2+ and { Cu-□-Cu} 2+ ，which in turn prevents the catalytic de⁃ composition of NO to N2 and O2 .