Volatile organic compound abatement

Plasma Catalysis for Volatile Organic Compounds Abatement... 

Emission abatement methods covered are suitable for the emission control of volatile organic compounds (VOCs). The VOCs include organic compounds existing in the gaseous phase in air at 293.15 K. However, or ganic compounds, which are not regarded as VOCs, can be treated by the methods covered in this section. 

The Econ-Abator system is a fluidized-bed catalytic oxidation system. Catalytic fluidized beds allow for destruction of volatile organic compounds (VOCs) at lower temperatures than conventional oxidation systems (typically 500 to 750°F). The technology uses a proprietary catalyst consisting of an aluminum oxide sphere impregnated with chromium oxide. 

A major opportunity for savings is to reduce the flow of diluent or carrier gas (often air or nitrogen) at the source. For a gas stream containing both particulates and halogenated volatile organic compounds (VOCs), the minimum capital investment to abate this stream is about 75 per standard cubic foot per minute (scfm) of waste gas flow. 

The air pollutants of volatile organic compoimds emitted from many industrial processes and transportation activities could be abated by catalytic combustion processes. Scire et al. reported the catalytic combustion of 2-propanol, methanol, and toluene on ceria-gold catalysts. The catalysts were prepared with coprecipitation and deposition-precipitation methods. The gold significantly enhanced the catalytic activity of ceria for the oxidation of these volatile organic compounds. The supposed reason is that the gold NFs weakened the mobility/reactivity of surface lattice oxygen (Scire et al., 2003). 

Since natural sunlight can only penetrate a few microns depth, the use of thin films of titania applied to ceramic or metallic supports as maintenance free decontamination catalysts for the photocatalytic oxidation of volatile organic compounds is of interest for the abatement or control of these emissions. The sol-gel technology can be readily incorporated as a washcoating step of the catalyst supports that may be subsequently heat-treated to fix the titania to the support. The surface area, porosity and crystalline phases present in these gels is important in controlling their catalytic activity. Furthermore, the thermal stability and development of porosity with heat-treatment was important if the sol-gel route is to be used as a washcoating step to produce thin films. 

The increasing amounts of chlorinated volatile organic compounds (VOC), such as 1,2-dichloroethane (DCE) and trichloroethylene (TCE), released in the environment, together with their suspected toxicity and carcinogenic properties, have prompted researchers world-wide to find clean effective methods of destruction [1]. The abatement of chlorinated volatile organic compounds by catalytic combustion has been widely utilised in several technical processes. The lower temperatures required for catalytic combustion result in a lower fuel demand and can therefore be more cost effective than a thermal oxidation process [2]. In addition, the catalytic process also exerts more control over the reaction products and is less likely to produce toxic by-products, like dioxins, which may be generated by thermal combustion [3]. 

We have dso examined these processes extensively, and this paper will summarize this research to produce syngas[7-9], olefinsflO], and oxygenates[ll]. In excess O2 similar processes produce primarily CO2 and H2O, and these processes are very important to reduce pollution from NOx, CO, and unbumed hydrocarbons in combustion to produce heat, ra ation, and for abatement of volatile organic compounds (VOCs) in air. 

In order to optimise the catalytic processes involving NOx abatement and total combustion of volatile organic compounds (VOC), it is prerequisite to elucidate the mechanism of these processes. In the lecture three processes will be discussed. 

The major problem to be addressed in the present paper is how the phenomenon of the surface transformations under the non-steady-state conditions can generally be applied for the NO abatement and for the combustion of volatile organic compounds (VOC). Two phenomena must be considered here ... 

The public awareness about the impact of human activity on the environment exerts a tremendous pressure on most industrial manufacturers and leads to the development of environmental-oriented catalysis. One of the main issues in this research field is the concern about the abatement of volatile organic compounds (VOC). Here, dilute VOC-containing effluent streams are by far the most prevalent, which makes their non-catalytic combustion an expensive operation since it requires a supplemental fuel supply [1]. The catalytic combustion, however, can be carried out at relatively low temperature with little or no... 

Understanding the deactivation processes that take place in oxidation catalysts used for volatile organic compound (VOC) abatement has both industrial and academic interest. The industrial importance of improving the deactivation resistance of catalysts used to remove VOC emissions is directly related to the economics of this process. The market for such equipment will grow significantly in the next few years. For example, in Europe the Solvent Emissions Directive adopted by the EU s Environmental Ministers in 1999 seeks to reduce VOC emissions from operations using solvents by 67 % by 2007, based 1990 levels. The EU member states have now adopted these directives into national law. 

Gervasini, A. and Ragaini, V, Catalytic technology assisted with ionization/ozonization phase for the abatement of volatile organic compounds Catai. Today. 2000. 60, 129-138... 

The application of zeolite catalysts to pollution abatement is also promising. The main pollutants in gaseous emissions that can be potentially treated by zeolites are volatile organic compounds (VOCs) and NOx. 

Biocatalytic desulfurization of diesel fuel Sulfur recovery using oxygen-enriched air California smog control Zero emissions from a THF plant Volatile organic compound (VOC) abatement—thermal incineration, catalytic incineration, or adsorption, for ozone control... 

The 1990 Clean Air Act requires the reduction of volatile organic compound (VOC) emissions. All VOC emission sources of 10 tons/year or greater are required to retrofit abatement processes using the best available control technology (BACT). 

ASTM D 5087-94. Standard test method for determining amount of volatile organic compound (VOC) released from solventbome automotive coatings and available for removal in a VOC control device (abatement). 

More recently, a new technology for NO removal has been proposed as an alternative to SCR. This technology with the trade name SCONOx (8) allows the abatement of NO, CO, and volatile organic compounds (VOC) and is based on a cyclic operation NO are stored on a catalyst/sorber material during the adsorption phase, whereas during the subsequent regeneration phase the adsorbed NO species are reduced to nitrogen. 

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