International Joint Laboratory of Catalytic Chemistry, College of Sciences, Shanghai University, Shanghai 200444, China.
Environ Sci Technol. 2022 May 17;56(10):6668-6677. doi: 10.1021/acs.est.2c00758. Epub 2022 May 2.
Selective catalytic reduction of NO in the presence of alkali (earth) metals and heavy metals is still a challenge due to the easy deactivation of catalysts. Herein, NO reduction over smart catalysts with self-created targeted antipoisoning sites is originally demonstrated. The smart catalyst consisted of TiO pillared montmorillonite with abundant cation exchange sites to anchor poisoning substances and active components to catalyze NO into N. It was not deactivated during the NO reduction process in the presence of alkali (earth) metals and heavy metals. The enhanced surface acidity, reducible active species, and active chemisorbed oxygen species of the smart catalyst accounted for the remarkable NO reduction efficiency. More importantly, the self-created targeted antipoisoning sites expressed specific anchoring effects on poisoning substances and protected the active components from poisoning. It was demonstrated that the tetrahedrally coordinated aluminum species of the smart catalyst mainly acted as self-created targeted antipoisoning sites to stabilize the poisoning substances into the interlayers of montmorillonite. This work paves a new way for efficient reduction of NO from the complex flue gas in practical applications.
由于催化剂易失活,因此在碱(土)金属和重金属存在下选择性催化还原 NO 仍然是一个挑战。本文首次展示了具有自创建靶向解毒位的智能催化剂上的 NO 还原。智能催化剂由钛柱撑蒙脱石组成,具有丰富的阳离子交换位,可固定毒害物质和活性组分以催化 NO 转化为 N。在碱(土)金属和重金属存在下的 NO 还原过程中,它并未失活。智能催化剂的增强的表面酸度、可还原的活性物种和活性化学吸附氧物种解释了其显著的 NO 还原效率。更重要的是,智能催化剂上的自创建靶向解毒位对毒害物质表现出特定的锚固效应,并保护活性组分免受毒害。实验表明,智能催化剂中的四面体配位铝物种主要作为自创建靶向解毒位将毒害物质稳定在蒙脱石的层间。这项工作为实际应用中从复杂烟道气中高效还原 NO 开辟了新途径。