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The partial electrochemical reduction of carbon dioxide (CO2) using ceramic oxygen generators (COGs) is well known and widely studied. Conventional COGs use yttria-stabilized zirconia (YSZ) electrolytes and operate at temperatures greater than 700 °C. Operating at a lower temperature has the advantage of reducing the mass of the ancillary components such as insulation and heat exchangers (to reduce the COG oxygen output temperature for comfortable inhalation). Moreover, complete reduction of metabolically produced CO2 (into carbon and oxygen) has the potential of reducing oxygen storage weight if the oxygen can be recovered. Recently, the University of Florida developed novel ceramic oxygen generators employing a bilayer electrolyte of gadolinia-doped ceria and erbia-stabilized bismuth oxide (ESB) for NASA's future exploration of Mars.

The removal of volatile organic compounds (VOCs) from the air aboard spacecrafts is necessary to maintain the health of crewmembers. The use of photocatalysis has proven effective for the removal of VOCs. A majority of studies have focused on thin films, which have a low adsorption capacity for contaminants and intermediate oxidation byproducts. Thus, this study investigates the use of adsorbent materials impregnated or coated with titania to: (1) provide a system that can remove VOCs for a period of time in the absence of UV irradiation to reduce power requirements and/or offer contaminant removal in the event of lamp failure and (2) improve the photocatalytic oxidation efficiency by concentrating VOCs and intermediate oxidation byproducts near the surface of the photocatalyst. Two adsorbent materials (porous silica gel and BioNuchar120 activated carbon) and glass beads were tested as catalyst supports for the destruction of a target VOC, in this case methanol (Co = 50 ppmv).

The technical feasibility of applying anaerobic digestion for reduction and stabilization of the organic fraction of solid wastes generated during space missions was investigated. This process has the advantages of not requiring oxygen or high temperature and pressure while producing methane, carbon dioxide, nutrients, and compost as valuable products. High-solids leachbed anaerobic digestion employed here involves a solid-phase fermentation with leachate recycle between new and old reactors for inoculation, wetting, and removal of volatile organic acids during startup. After anaerobic conversion is complete, the compost bed may be used for biofiltration and plant growth medium. The nutrient-rich leachate may also be used as a vehicle for nutrient recycle. Physical properties of representative waste feedstocks were determined to evaluate their space requirements and hydraulic leachability in the selected digester design.

Previous work demonstrated that the Photo-Cat® developed by Purifics is capable of reducing the total organic carbon (TOC) concentration of 51 mg/L to below 0.5 ppm using Degussa P25 titanium dioxide (TiO2) as a photocatalyst. The work also showed that ammonium bicarbonate had a detrimental effect on the rate of photocatalytic oxidation, but did not prevent the system from reaching the potable water specification. Nanometer sized Degussa P25 is very popular and quite frequently used as a benchmark of performance in literature, but it may not be the most effective for oxidizing all waste streams. It is critical that each component of the water recovery system be optimized for power consumption and the effectiveness of the photocatalyst plays an important role in accomplishing this.

This paper describes an opportunity for commercial application of NASA space-based technology. Specifically, it describes application of the University of Florida's patented space-based SEBAC-II solid waste management technology to the US beet sugar industry. The project is entitled “Conversion of Biomass into Energy and Compost through Sequential Batch Anaerobic Composting”, and is being funded by the Xcel Energy Renewable Development Fund. It will be carried out by a team of researchers from the University of Florida in partnership with American Crystal Sugar Company (ACSC) of Moorhead, MN, and Minnesota Technology Inc. (MTI) in Minneapolis, MN. American Crystal Sugar generates 400 tons of sugar beet tailings daily. These tailings are a waste by-product of the raw sugar beet receiving, handling and washing operations. Currently, the company pays to have this material hauled away at the rate of 16 truckloads per day.

Finding a manner to effectively filter water to the purest standards is an ongoing battle for various sectors of science. We present a set of experiments that will report the preparation of the photocatalytic component of our composite particle via sol-gel coatings with titanium n-butoxide with subsequent heat treatment at 500°C for three hours in Argon. Our ultimate goal is to create a particle with regenerative capabilities along with a surface enhanced Raman scattering effect. Characterization techniques were performed using SEM-EDS, and XRD.