PDF(Pubmed)
Abstract：
Barium and iridium supported on Zeolite Socony Mobil-5 (ZSM-5) are efficient catalysts for the selective catalytic reduction of nitric oxide by carbon monoxide (CO-SCR), with enhanced cyclic stability. The introduction of Ba hindered the oxidation of metallic Ir active species and enabled Ir to maintain an active metallic state, thereby preventing a decrease in catalytic activity in the CO-SCR reaction. Moreover, the Ba modification increased the NO adsorption of the catalyst, further improving the catalytic activity. Owing to the better anti-oxidation ability of Ir0 in IrBa0.2/ZSM-5(27) than in Ir/ZSM-5(27), IrBa0.2/ZSM-5(27) showed better stability than Ir/ZSM-5(27). Considering that all samples in the present study were tested to simulate actual flue gases (such as sintering flue gas and coke oven flue gas), NH3 was introduced into the reaction system to serve as an extra reductant for NOx. The NOx conversion to N2 (77.1%) was substantially improved using the NH3-CO-SCR system. The proposed catalysts and reaction systems are promising alternatives for treating flue gas, which contains considerable amounts of NOx and CO in oxygen-enriched environments.
摘要：
负载在沸石SoconyMobil-5（ZSM-5）上的钡和铱是一氧化碳（CO-SCR）选择性催化还原一氧化氮的有效催化剂，具有增强的循环稳定性。Ba的引入阻碍了金属Ir活性物质的氧化，并使Ir保持活性金属状态，从而防止CO-SCR反应中催化活性的降低。此外，Ba改性增加了催化剂对NO的吸附，进一步提高催化活性。由于IrBa0.2/ZSM-5(27)中Ir0的抗氧化能力优于Ir/ZSM-5(27),IrBa0.2/ZSM-5(27)显示出比Ir/ZSM-5(27)更好的稳定性。考虑到本研究中的所有样品都经过了模拟实际烟气（例如烧结烟气和焦炉烟气）的测试，将NH3引入到反应体系中以用作NOx的额外还原剂。使用NH3-CO-SCR系统显著改善了NOx到N2的转化率(77.1%)。拟议的催化剂和反应系统是处理烟气的有前途的替代品，在富氧环境中含有大量的NOx和CO。
