Ionization systems configured with a catalyst-bearing sleeve provide improved filtration while keeping ozone levels within acceptable limits. Modular configurations provide for serviceability and replaceability. System controls monitor particulates, temperature, humidity, and other relevant factors and adjust an ionization level accordingly for optimal performance.

The disclosure provides a system and a method for reducing hazardous gases, including PHGs, through one or more photocatalysts in a filter system. A microstructure of the photocatalytic filter can be formed using biological systems as a template for the photocatalysts to be deposited thereon. The biological system can be removed by heat, oxidation, or by chemical processes to leave the photocatalytic template as a filter for the gases. In various embodiments, multiple photocatalysts can be activated at different wavelengths to filter different gases, or multiple photocatalysts can be activated at the same wavelength to filter different gases, or a photocatalyst can be activated at different wavelengths to filter different gases, or some combination thereof. The activation can be sequential or concurrent. For multiple layers of photocatalysts, the sequence of the photocatalysts can be arranged to reduce damaging output from an upstream photocatalyst to one or more downstream photocatalysts.

A porous ceramic structure with low pressure loss and high catalytic performance is provided. The porous ceramic structure includes a porous structure body (i.e., honeycomb structure) composed primarily of cordierite, and manganese (Mn) and tungsten (W) that are fixedly attached to the honeycomb structure. Thus, pressure loss in the porous ceramic structure can be reduced, and an NO combustion temperature in the porous ceramic structure can be lowered. In other words, the aforementioned structure of the porous ceramic structure allows the porous ceramic structure to have low pressure loss and high catalytic performance.

Zero-Rare Earth Metal (ZREM) and Zero-platinum group metals (ZPGM) compositions of varied binary spinel oxides are disclosed as oxygen storage material (OSM) to be used within TWC systems. The ZREM-ZPGM OSM systems comprise binary non-Cu spinel oxides of Co—Fe, Fe—Mn, Co—Mn, or Mn—Fe. The oxygen storage capacity (OSC) property associated with the non-Cu ZREM-ZPGM OSM systems is determined employing isothermal OSC oscillating condition testing. Further, the OSC test results compare the OSC properties of a ZREM-ZPGM reference OSM system including a Cu—Mn binary spinel oxide and PGM reference catalysts including Ce-based OSMs. The non-Cu spinel oxides ZREM-ZPGM OSM systems exhibit significantly improved OSC properties, which are greater than the OSC property of the Ce-based OSM PGM reference systems.

Synergized platinum group metals (SPGM) with ultra-low PGM loadings employed as close-coupled (CC) three-way catalysts (TWC) systems with varied material compositions and configurations are disclosed. SPGM CC catalysts in which ZPGM compositions of binary or ternary spinel structures supported onto support oxides are coupled with commercialized PGM UF catalysts and tested under Federal Test Procedure FTP-75 within TGDI and PI engines. The performance of the TWC systems including SPGM CC (with ultra-low PGM loadings) catalyst and commercialized PGM UF catalyst is compared to the performance of commercialized PGM CC and PGM UF catalysts. The disclosed TWC systems indicate that SPGM CC TWC catalytic performance is comparable or even exceeds high PGM-based conventional TWC catalysts, with reduced tailpipe emissions.

Synergized platinum group metals (SPGM) with ultra-low PGM loadings employed as underfloor (UF) three-way catalyst (TWC) systems with varied material compositions and configurations are disclosed. SPGM UF catalysts in which ZPGM compositions of binary and ternary spinel structures supported onto support oxides are coupled with commercialized PGM close-coupled (CC) catalysts and tested under Federal Test Procedure FTP-75 within TGDI and PI engines. The performance of the TWC systems including commercialized PGM CC and SPGM UF (with ultra-low PGM loadings) catalysts is compared to the performance of commercialized PGM CC and PGM UF catalysts. The disclosed TWC systems indicate that SPGM UF TWC catalytic performance is comparable or even exceeds high PGM-based conventional TWC catalysts, with reduced tailpipe emissions.

An exhaust gas treatment device capable of treating exhaust gas of a gas turbine or a gas engine includes an exhaust gas treatment catalyst comprising a perovskite composite oxide containing at least Ag and Dy in an A site and at least Mn in a B site.

An exhaust system for an internal combustion engine, the exhaust system comprising, a lean NO.sub.x trap (LNT), a wall flow monolithic substrate having a NO.sub.x storage and reduction zone thereon, the wall flow monolithic substrate having a pre-coated porosity of 40% or greater, the NO.sub.x storage and reduction zone comprising a platinum group metal loaded on a first support, the first support comprising one or more alkaline earth metal compounds, a mixed magnesium/aluminium oxide, cerium oxide, and at least one base metal oxide selected the group consisting of copper oxide, manganese oxide, iron oxide and zinc oxide.

Provided herein is a device for removing residual hydrogen peroxide or hydrazine from an effluent gas stream which includes a metal oxide scrubber material configured to react with residual process gases under increased temperatures. Also provided are systems and methods of using the same.

A structured monolithic catalyst has a structured monolithic carrier and a coating of active components. The coating of active components comprises active metal components and a substrate. The active metal components conclude a first metal element, a second metal element, a third metal element and a fourth metal element. The first metal element includes Fe and Co; the second metal element is at least one selected from the group consisting of the metal elements of the Group IA and/or IIA; the third metal element is at least one selected from the group consisting of the non-noble metal elements of the Groups IB to VIIB; and the fourth metal element is at least one selected from the group consisting of the noble metal elements.