Air, purification

These fibers may find use in controUed release of dmgs, bactericides, and corrosion prevention chemicals (103). Fibers with different active groups have been made for sorption of chemicals. These fibers are designed to replace granular sorbents for air purification, for example, in air filtration masks (104). 

Translating odor modifiers into consumer products results in forms, such as soHds, Hquids, and aerosols, for a market defined as products "for the nose." This includes products that cover up or eliminate odors, perfume the home, or cleanse the air. Such products thus defined were reported to have sales in 1992 of just under 2 biUion. The categories of this market can be broken out as traditional air fresheners, cat Utter products, aroma care, air purification, and disinfectant in both consumer and industrial appUcations. 

The air process has similar purity requirements to the oxygen process. The ethane content of ethylene is no longer a concern, due to the high cycle purge flow rate. Air purification schemes have been used to remove potential catalyst poisons or other unwanted impurities ia the feed. 

Possible role of the induced acidity and basicity in catalysis and environmental chemistry is discussed. The suggested mechanism explains the earlier reported promotive effect of some gases in the reactions catalyzed by Bronsted acid sites. Interaction between the weakly adsorbed air pollutants could lead to the enhancement of their uptake by aerosol particles as compared with separate adsoi ption, thus favoring air purification. 

Low-temperature spectroscopy is indispensable for the studies of processes on the ice surface, illustrated by ozone adsorption and ethylene ozonolysis. Such results are important to clarify the mechanism of atmospheric pollutant elimination and air purification in the nature. 

Bameby Sutcliffe Site describes company providing activated carbon, air purification, solvent recovery, emission control, remediation, odor control, corrosive gas control, pollution control, air filterr, and distillation equipment. http //www.bscarbons.com... 

White, D.A., Assabumrungrat, S., Puttick, S., Sizing of inorganic micro filtration monoliths for water and air purification, Trans.of the IChemE, V.73B, pp. 108-114, 1995. 

The challenges to be faced in air-purification systems using photocatalysis involve the treatment of relatively large gas flows in devices with low pressure drops, good catalyst irradiation, and efficient reactant species as well as good photocatalyst contacting [51-53]. 

The oxidative degradation of organic pollutants in water and air streams is considered as one of the so-called advanced oxidation processes. Photocatalytic decomposition of organics found widespread industrial interest for air purification (e.g., decomposition of aldehydes, removal of NO , ), deodorization, sterilization, and disinfection. Domestic applications based on Ti02 photocatalysts such as window self-cleaning, bathroom paints that work under illumination with room light, or filters for air conditioners operating under UV lamp illumination have already been commercialized. Literature-based information on the multidisciplinary field of photocatalytic anti-pollutant systems can be found in a number of publications, such as Bahnemann s [237, 238] (and references therein). 

One of the most important fields of application of photocatalysis is the photodegeneration of organic compounds. These processes are used in particular for environmental decontamination, especially for wastewater treatment and air purification, because of the ability of semiconductors to totally degrade organics to C02, H 20, and inorganic anions under U V or visible light. This behavior is attributed to the photoinduced formation of radicals, such as OH, or to the adsorption and direct degradation of the pollutants. 

High concentrations of cyanides and cyanogen halides can rapidly degrade elements of some air purification filters. Care should be taken whenever using APRs in the presence of these agents. 

To remain effective, an air purification system must be properly maintained and periodically tested. Table 6.2 summarizes the advantages and disadvantages of several options for removing airborne contaminants from the air. 

Using a portable air purification system (e.g., the CARE 2000 air defense system) fitted with appropriate filters to remove contaminants from air already present in the building... 

Only three of the stated objectives (Fig. 12.8-2) are relevant for this assessment phase. They are (1) air purification performance (50 %), reliability (25 %) and cost (25 %). In the absence of hard data, the members of the project team were... 

During controlled exposures of human subjects to specific compounds like ozone, the concentrations of suspended particles and trace gases must be known and minimized to ensure that health effects can be attributed solely to ozone. The air purification units for the environmental chambers are designed to remove most of the particles and pollutant gases from the ambient air. Prefilters and efficient absolute filters are used to remove 99% of the particles with diameters of 0.3 nin... 

Gas Separation (GS) pressure difference oxygen enriched air purification of natural gas... 

Doyle, G. J., P. J. Bekowies, A. M. Winer, and J. N. Pitts, Jr., Charcoal-Adsorption Air Purification System for Chamber Studies Investigating Atmospheric Photochemistry, Environ. ScL TechnoL, 11, 45-51 (1977). 

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