Center Independent Research & Development: KSC IRAD
Completed Technology Project (2015 - 2016)
Photocatalytic oxidation (PCO) is a primary candidate as an alternative to thermal-catalytic or sorbent- based technologies for VOC trace contaminant control due to its low energy demand, operation near room temperatures, and minimal logistic costs. A unique annular adsorption-enhanced Silica-Titania Composite (STC) UV-Photocatalytic Oxidation (PCO) reactor had been used at KSC to test and understand the interactions of the UV light and STC pellets and to further technological understanding of PCO for real world applications. From these tests a new unique design of a hybrid approach utilizing a PCO reactor and sorbent materials was realized and extensively modeled here at KSC. The objective of this study is to construct the bench-scale version of this modeled Hybrid PCO reactor and validate its effectiveness in the reduction of trace air contaminates. If successful, the TRL level will increase from a 2 to a 4 with the manufacturing of scaled prototype of this PCO reactor.
To validate the efficiency of the modeled hybrid PCO, a bench scale reactor incorporating the modeled geometry, catalyst support medium, and UV-C illumination will be fabricated with technical assistance/engineering support leveraged with UF, private corporations, and the KSC Prototype Shop. The PCO reactor catalysts will be characterized. A bench scale version of this HPCO unit will be designed, constructed and then challenged with predominant polar VOC’s, including ethanol, as it constitutes the primary contaminant aboard spacecraft. The test bed, which includes a Kin-tek VOC generator, a PCO reactor, and an FTIR analyzer, was used successfully in previous PCO studies in the Air Revitalization at KSC, and will be available for validation of the H-PCO reactor efficiency.
Closed confined environments of the ISS, as well as in future spacecraft for exploration beyond LEO, will require a robust, re-generable air revitalization system that can minimize trace VOC contaminants and enhance life cycle economics of ECLSS subsystems. The current air revitalization technology involves thermal-catalytic and/or sorbent based technologies with considerable power requirements, heat load, and consumable support. The development of a hybrid UV-PCO system could ultimately lead to significant design changes in future trace contaminant control systems.
Technical advances in such technologies have many applications outside of NASA. Firstly, home and office air conditioning systems could incorporate HPCO technologies for air purification. Secondly, aircraft and car manufacturers could utilize this technology for both biological air sanitization and VOC removal from cabin air.
This technology could be incorporated in commercial air revitalization system.