贵金属(Pt、Pd和Ru)基催化剂在含氯挥发性有机物催化降解中的研究进展

Research progresses of noble metal(Pt,Pd,and Ru)-based catalysts forcatalytic decomposition of chlorine-containing volatile organic compounds

含氯挥发性有机物(Chlorine-containing volatile organic compounds,CVOCs)由于存在来源广泛、生物/环境毒性高、易使催化剂Cl中毒失活等问题,是当前VOCs控制领域的研究重点和难点。催化降解技术具有能耗低、效率高、二次副产物少等显著优点被认为是最有效的CVOCs排放控制技术之一。高性能催化剂是该技术的核心。目前,CVOCs降解催化剂主要以Al_(2)O_(3)、TiO_(2)、MgO、CeO_(2)等单一或复合金属氧化物为载体,以Pt、Pd、Ru等为反应活性中心。在CVOCs氧化反应中,贵金属在低温下易与Cl作用,覆盖/惰化活性位,导致催化剂低温活性下降。常用的提升负载型贵金属催化剂CVOCs催化性能的策略有金属助剂掺杂、活性中心状态优化、载体性质调控、反应条件调节等。本文综述了贵金属(Pt、Pd和Ru)基催化剂在CVOCs催化氧化中的研究进展,主要集中于过渡金属引入、载体本征性质调变、反应条件调节等在CVOCs转化效率及催化剂性能改善中的作用。此外,对CVOCs催化净化催化剂的发展方向提出了展望。

Chlorine-containing volatile organic compounds(CVOCs)have become a focus and difficulty in the field of catalytic combustion of VOCs due to their extensive sources,high biological/environmental toxicity,and easy inactivation of catalyst via Cl poisoning.Catalytic decomposition is considered to be one of the most effective and feasible methods to reduce the emissions of CVOCs due to its significant advantages of low energy consumption,high efficiency and less secondary by-products.High performance catalysts are the key to this technology.At present,the CVOCs degradation catalysts are mainly composed of single or complex metal oxide supports(e.g.,Al_(2)O_(3),TiO_(2),MgO,and CeO_(2))and noble metal(e.g.,Pt,Pd,and Ru)reactivity center.In the oxidation reaction of CVOCs,the noble metal is easy to interact with Cl at low temperature,covering/inerting the active site,and resulting in a decrease in the low-temperature activity of the catalyst.Commonly strategy to improve the catalytic performance of supported precious metal catalysts include metal additive doping,active center state optimization,carrier property regulation,reaction condition adjustment,etc.In this review,we briefly review the research progress of noble metal(Pt,Pd,and Ru)-based catalysts in the catalytic oxidation of CVOCs,including doping transition metals,changing the intrinsic properties of supports,and adjusting reaction conditions to improve catalytic efficiency and performance.In addition to this,the future perspectives toward the development of CVOC purification catalysts are put forward.