It is well known that urbanization and industrialization have resulted in the rapidly increasing emissions of volatile organic compounds (VOCs), which are a major contributor to the formation of secondary pollutants (e.g., tropospheric ozone, PAN (peroxyacetyl nitrate), and secondary organic aerosols) and photochemical smog. The emission of these pollutants has led to a large decline in air quality in numerous regions around the world, which has ultimately led to concerns regarding their impact on human health and general well-being. Catalytic oxidation is regarded as one of the most promising strategies for VOC removal from industrial waste streams. This Review systematically documents the progresses and developments made in the understanding and design of heterogeneous catalysts for VOC oxidation over the past two decades. It addresses in detail how catalytic performance is often drastically affected by the pollutant sources and reaction conditions. It also highlights the primary routes for catalyst deactivation and discusses protocols for their subsequent reactivation. Kinetic models and proposed oxidation mechanisms for representative VOCs are also provided. Typical catalytic reactors and oxidizers for industrial VOC destruction are further discussed. We believe that this Review will provide a great foundation and reference point for future design and development in this field.

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Recent Advances in the Catalytic Oxidation of Volatile Organic Compounds: A Review Based on Pollutant Sorts and Sources.

Abatement of various types of VOCs by adsorption/catalytic oxidation: A review

A critical review on VOCs adsorption by different porous materials: Species, mechanisms and modification methods.

Volatile organic compounds (VOCs) with the properties of volatility, toxicity and diffusivity pose a serious threat to human health and eco-environment. Catalytic oxidation technology has been considered as a highly efficient option for the treatment of VOCs. This review systematically summarizes the recent processes and advances on catalytic elimination of VOCs over nanoparticles catalysts. Firstly, catalytic performances of catalysts for VOC degradation are evaluated and compared on the basis of unified performance metrics. Secondly, catalytic mechanisms of VOC oxidation, based on experimental and theoretical studies, are systematically introduced. Then, catalytic reactors employed in VOC elimination processes are summarized. In particular, photothermocatalysis by integrating (thermo)catalysis with photocatalysis is also elucidated. Lastly, the perspectives to the scientific issues and challenges faced, as well as the future outlooks are proposed. Collectively, this review will provide theoretical and experimental foundation for rational fabrication and application of nanoparticles catalysts toward VOC elimination in future.

Recent advances in VOC elimination by catalytic oxidation technology onto various nanoparticles catalysts: a critical review

In recent decades, the environmental protection and long-term sustainability have become the focus of attention due to the increasing pollution generated by the intense industrialization. To overcome these issues, environmental catalysis has increasingly been used to solve the negative impact of pollutants emission on the global environment and human health. Supported platinum-metal-group (PGM) materials are commonly utilized as the state-of-the-art catalysts to eliminate gaseous pollutants but large quantities of PGMs are required. By comparison, single-atom site catalysts (SACs) have attracted much attention in catalysis owing to their 100% atom efficiency and unique catalytic performances towards various reactions. Over the past decade, we have witnessed burgeoning interests of SACs in heterogeneous catalysis. However, to the best of our knowledge, the systematic summary and analysis of SACs in catalytic elimination of environmental pollutants has not yet been reported. In this paper, we summarize and discuss the environmental catalysis applications of SACs. Particular focus was paid to automotive and stationary emission control, including model reaction (CO oxidation, NO reduction and hydrocarbon oxidation), overall reaction (three-way catalytic and diesel oxidation reaction), elimination of volatile organic compounds (formaldehyde, benzene, and toluene), and removal/decomposition of other pollutants (Hg0 and SO3). Perspectives related to further challenges, directions and design strategies of single-atom site catalysts in environmental catalysis were also provided.

https://link.springer.com/content/pdf/10.1007/s12274-020-2994-3.pdf

Single-atom site catalysts for environmental catalysis

Different amounts of silver were successfully incorporated into cryptomelane-type manganese oxide (K-OMS-2) via a one-step hydrothermal method for application in the catalytic combustion of benzene. Silver incorporation could promote the benzene oxidation performance of the catalysts. The silver doping effect was addressed in terms of the relationship between structure and activity. The prepared catalysts were characterized by ICP-OES, BET, XRD, Raman, FE-SEM, TEM, XPS, XAFS, H2-TPR and CO-TPD. The best precursor Mn/Ag mole ratio was 40. The resulting K/Ag-OMS-40 catalyst exhibited the highest activity in terms of benzene combustion and good tolerance to chlorine poisoning, all of which make it a promising candidate as an alternative to noble metal supported catalysts. All catalysts after silver incorporation maintained the structural integrity of the cryptomelane structure but with decreased crystalline size, which significantly increased the surface area and number of defects of the catalyst. The silver species, mostly in the form of Ag+, were well dispersed and partially replaced K+ in the tunnels of cryptomelane. K/Ag-OMS-40 had the largest surface area, the smallest nanorods and most abundant Mn octahedral defects. The large number of active oxygen species derived from the high Mn3+ content and Ag-O-Mn bridge bonds appeared to play critical roles in VOC decomposition.

Silver incorporated into cryptomelane-type Manganese oxide boosts the catalytic oxidation of benzene

Manganese oxides are prominent candidates for the catalytic oxidation of volatile organic compounds (VOCs) or ambient decomposition of O3 individually. Here, we compared various preparation methods...

Shunyu Kang

Papers

Silver incorporated into cryptomelane-type Manganese oxide boosts the catalytic oxidation of benzene

Role of Structural Defects in MnOx Promoted by Ag Doping in the Catalytic Combustion of Volatile Organic Compounds and Ambient Decomposition of O3.

Palladium supported on low-surface-area fiber-based materials for catalytic oxidation of volatile organic compounds

Significant enhancement in water resistance of Pd/Al2O3 catalyst for benzene oxidation by Na addition

Facile homogeneous precipitation method to prepare MnO2 with high performance in catalytic oxidation of ethyl acetate