Air purification technologies

Corona discharge air purification technology Fixed site decontamination system Lightweight portable decontamination system... 

The photocatalyzed oxidation of gas-phase contaminants in air has been demonstrated for a wide variety of organic compounds, including common aromatics like benzene, toluene, and xylenes. For gas-phase aromatic concentrations in the sub-lOO-ppm range, typical of common air contaminants in enclosed spaces (office buildings, factories, aircraft, and automobiles), photocatalytic treatment leads typically to complete oxidation to CO2 and H2O. This generality of total destruction of aromatic contaminants at ambient temperatures is attractive as a potential air purification and remediation technology. 

Formenti, M. Juillet, F. Meriaude, P. Teichner, S. J. Chem. Technol. 1971,1, 680. Bendfeldt, P. Hall, R. J. Obee, T. N. Hay, S. O. Sangiovanni, J. J. A. Eeasibility Study of Photocatalytic Air Purification for Commercial Passenger Airliners United Technologies Research Center Hartford, CT, 1997. 

Large-scale installations of air purification by Ti02 photocatalysis have been built and operated in North America by Trojan Technologies, Inc. (143) and United Technologies of Connecticut (144) (Fig. 6). The objective was to avoid polluting groundwater by chlorinated aliphatic... 

Membrane technology is also an ideal technology for application in the space because process intensification strategy is a more imperative request in the space than on the Earth, today. Volumetric efficiency, optimal remote control, energy, and waste saving are fundamental aspects in the space. Membranes could efficiently solve some of the problems of life in the space such as energy production and water and air purification, fulfilling these requirements. 

Obtaining insight into charge transfer processes is important in order to improve the photoconversion efficiencies in semiconductor-based nanoassemblies. The principles and mechanism of photocatalytic reactions in advanced oxidation processes can be found in earlier review articles [40-42]. Technological advances in this area have already led to the product development for a variety of day-to-day operations. Commercialization of products such as self-cleaning glass, disinfectant tiles and filters for air purification demonstrate the initial success of nanosystems for environmental applications [43]. 

A quite different technique is necessary when a stabilising adsorption layer on the particle surface is formed. Apparently it is necessary to provide reversibility of surfactant adsorption so that a decrease of surfactant concentration in the bulk results in desorption. This decrease is used in water purification technology based on adsorption methods. Specifically, if a surfactant stabilises the adsorption layers on particles and also adsorbs at the water-air interface, a preliminary flotation of surfactant can decrease their adsorption and thus destabilise the particles. Then microflotation can be applied to extract destabilised particles. 

Efforts in this area include protective clothing, protective masks, air purification, and shelters. The effective level of protection and the capabilities of the fielded equipment will increasingly depend on the transition of new materials and processing concepts to manufacturing. Successful utilization of nanoscale materials technology is expected to result in a significant improvement in warfighter protection over that provided today. A number of scenarios in the four worlds of 2030 are shown in Fig. 3.1. 

Favre, E., R. Bounaceur, and R. Denis, A hybrid process combining oxygen enriched air combustion and membrane separation for post-combustion carbon dioxide capture. Separation and Purification Technology, 2009. 68(1) 30-36. 

Raeder, H., Bredesen, R., Crehan, G, Miachon, S., Dalmon, J.A., Pintar, A., Levee, J., Torp, E.G., 2003. A wet air oxidation process using a catalytic membrane contactor. Separation and Purification Technology 32,349-355. 

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