柴油车被动式NO_(x)吸附剂(PNAs)的研究进展  

Research Progress on Passive NO_(x)Adsorbers(PNAs)for Diesel Vehicles

作　　者：高传 李佳幸 李一凡 隆云鹏 李俊华[1] 彭悦[1] GAO Chuan;LI Jiaxing;LI Yifan;LONG Yunpeng;LI Junhua;PENG Yue(School of Environment,Tsinghua University,Beijing 100084,China)

机构地区：[1]清华大学环境学院,北京100084

出　　处：《能源环境保护》2025年第2期1-15,共15页Energy Environmental Protection

基　　金：国家自然科学基金资助项目(22276104)。

摘　　要：柴油车冷启动阶段是NO_(x)排放的主要阶段,对环境污染和人体健康造成了严重威胁。应用被动式NO_(x)吸附剂(Passive NO_(x)Adsorber,PNA)是实现柴油车NO_(x)超低排放的有效措施。系统综述了PNA领域在材料设计、机理探究和性能评估方面的最新进展。首先从吸/脱附性能、氧化活性、稳定性等方面,讨论了过渡金属氧化物和分子筛2种类型PNA材料的优缺点。然后从含氮物种的迁移转化层面,提出了2套NO_(x)吸附-脱附机理,即NO_(x)以亚硝酸盐/硝酸盐形式存储分解的吸附氧化脱附机理和以离子络合物形式存储释放的吸附络合脱附机理。此外,论述了气体组分(H_(2)O、CO、HC)、水热老化以及磷硫化学中毒对PNA材料的NO_(x)吸附-脱附行为的影响。最后,基于目前研究进展,提出了PNA材料未来研究的主要挑战。The cold start phase of diesel engines represents a critical stage for nitrogen Oxides(NO_(x))emissions,which pose significant challenges to environmental sustainability and public health.During this phase,the exhaust gas temperature remains low,making conventional selective catalytic reduction(SCR)systems ineffective.To address this issue,passive NO_(x)adsorbers(PNAs)have emerged as an effective solution for achieving ultra-low NO_(x)emissions,serving as pivotal components in nextgeneration diesel exhaust aftertreatment systems.These materials are designed to capture NO_(x)at low temperatures and subsequently release them when the exhaust reaches higher temperatures,allowing efficient mitigation through downstream SCR catalysts.This review systematically explores recent advancements in PNA technology,focusing on materials design strategies,reaction mechanisms,and performance evaluation.Transition metal Oxides(e.g.,CeO_(2),Co_(3)O_(4),and Ru/CeO_(2))and zeolites(e.g.,Pd/SSZ-13,Pd/BEA,and Co/SSZ-13)are two typical types of materials currently being studied in the PNAs;they exhibit unique advantages and are discussed in terms of their adsorption/desorption performance,Oxidizing activity,and thermal stability.Transition metal Oxides exhibit superior catalytic Oxidation abilities for CO and hydrocarbons(HCs),and good NO_(x)storage,with CeO_(2)achieving adsorption capacities up to 0.32 mmol/g at 30℃.In contrast,zeolites possess unique pore structure,large specific surface areas,and exceptional hydrothermal stability(e.g.,Pd/SSZ-13 maintaining performance after 1000℃hydrothermal aging).Further discussion on the role of precious metals and the potential of non-precious metal-based zeolites in PNA application is presented.Considering the distinct physicochemical properties of the above materials,a detailed discussion of the NO_(x)adsorptiondesorption mechanisms is proposed.The first mechanism,the NO_(x)Oxidative storage mechanism,primarily occurs on metal Oxide surfaces and involves NO_(x)storage as nitrite/nitrate,a

关 键 词：被动式NO_(x)吸附剂 NO_(x) 柴油排放后处理 过渡金属氧化物 分子筛 

分 类 号：X505[环境科学与工程—环境工程] X701