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

Manganese dioxide (MnO2 ) is a promising photo-thermo-electric-responsive semiconductor material for environmental applications, owing to its various favorable properties. However, the unsatisfactory environmental purification efficiency of this material has limited its further applications. Fortunately, in the last few years, significant efforts have been undertaken for improving the environmental purification efficiency of this material and understanding its underlying mechanism. Here, the aim is to summarize the recent experimental and computational research progress in the modification of MnO2 single species by morphology control, structure construction, facet engineering, and element doping. Moreover, the design and fabrication of MnO2 -based composites via the construction of homojunctions and MnO2 /semiconductor/conductor binary/ternary heterojunctions is discussed. Their applications in environmental purification systems, either as an adsorbent material for removing heavy metals, dyes, and microwave (MW) pollution, or as a thermal catalyst, photocatalyst, and electrocatalyst for the degradation of pollutants (water and gas, organic and inorganic) are also highlighted. Finally, the research gaps are summarized and a perspective on the challenges and the direction of future research in nanostructured MnO2 -based materials in the field of environmental applications is presented. Therefore, basic guidance for rational design and fabrication of high-efficiency MnO2 -based materials for comprehensive environmental applications is provided.

MnO2 -Based Materials for Environmental Applications.

Review on noble metal-based catalysts for formaldehyde oxidation at room temperature

Although manganese oxide (MnO2) exhibits excellent activity in various oxidation reactions, especially for volatile organic compound oxidation, the origin of the catalytic activity remains ambiguou...

Investigation into the Catalytic Roles of Various Oxygen Species over Different Crystal Phases of MnO2 for C6H6 and HCHO Oxidation

Nano-sized gold particles dispersed on HZSM-5 and SiO2 substrates for catalytic oxidation of HCHO

Although CoMn oxides have shown promising catalytic properties in HCHO oxidation, their activities have a large space to improve especially at low temperatures (

New insights into alkaline metal modified CoMn-oxide catalysts for formaldehyde oxidation at low temperatures

Utilization of Fe-Beta for NH3-SCR of NOx in diesel engine applications is severely limited by hydrocarbon poisoning. In this work, a series of hybrid catalysts are prepared by mechanical mixing of zeolites and oxides, and their activity for the selective catalytic reduction of NOx with NH3 is investigated in the presence of propene. Results have shown that a catalyst prepared by mixing Fe-Beta and MnOx/CeO2 in a mass ratio of 1:1 exhibits high SCR activity. NOx conversion in the temperature range 200–400 °C has exceeded 90% at a GHSV of 80,000 h−1, with low selectivity to N2O. By the combined DRIFTS and MS measurements, the function of MnOx/CeO2 in the hybrid catalysts is discussed. This hybrid catalyst is able to convert C3H6 to intermediates containing C O and COO functionalities, thereby decreasing carbon deposition on the zeolite and reduce the competitive adsorption between C3H6 and NOx. Moreover, these intermediates react with NOx at lower temperatures than do the carbonaceous deposits on Fe-Beta, enhancing the NOx reduction activity.

Limei Yu

Papers

Investigation into the Catalytic Roles of Various Oxygen Species over Different Crystal Phases of MnO2 for C6H6 and HCHO Oxidation

Nano-sized gold particles dispersed on HZSM-5 and SiO2 substrates for catalytic oxidation of HCHO

New insights into alkaline metal modified CoMn-oxide catalysts for formaldehyde oxidation at low temperatures

Hybrid catalysts with enhanced C3H6 resistance for NH3-SCR of NOx

Gold stabilized on various oxide supports catalyzing formaldehyde oxidation at room temperature