| Treatment and reuse of humidity condensate is a feasible way to supply potable wate in manned spacecraft and is a crucial component of the manned space exploration program for extended duration in the environment of space. Based on the inherent shortcomings of currently available technology in treating humidity condensate and the conventional treatment technologies are hardly used in treating humidity condensate in the microgravity environment of manned spacecraft, Exploratory study was done in treating humidity condensate. Based on the characteristics of special environment and humidity condensate, a composite technology of wet oxidation-ion exchange-disinfection was investigated in treating humidity condensate in this paper.In the wet oxidation unit, a new type of catalytic reactor, membrane aeration wet oxidation reactor was studied. In the reactor, a membrane module was employed, and the membrane module acted as a membrane bubbleless aerator. Oxygen permeated the membrane module into the reactor, and reacted with organic contaminants in humidity condensate catalyzed by Pt catalyst. The difficult problem of gas-liquid separation in the microgravity environment was avoiding. The removal rate of ethanol in humidity condensate was studied under various reaction conditions using the reactor. It was found that the removal rate of ethanol increasing when the membrane aeration pressure increased, and the removal rate of ethanol increased and the generation rate of acetic acid decreased as the liquid hydraulic retention time increased, and the the mass transfer coefficient had a deep influence on catalytic reaction. The removal rate of ethanol in humidity condensate was above 90% after being treated by the reactor. Because of the well-distributed of hollow fibre membrane in the reactor, the treatment efficiency of the reactor using hollow fibre membrane was higher than the reactor using flat membrane in treating ethanol in humidity condensate.The coating-type Pt catalysts were prepared by the method of impregnation reduction, and the catalysts were used in catalytic degradation of ethanol which was the main contaminant in humidity condensate. The factors that affected the activity of the catalysts were studied, then the preparing process of the catalysts was optimized, and the structures of the catalysts were characterized. The result indicated that the activity of Pt/AC was higher than the activity of Pt catalysts used other supports in catalytic degradation of ethanol. With the analysis of XRD,XPS and SEM, the active component Pt of catalyst was existed as the type of structure Pt0. After activated carbon support was pretreated with H2O2, the activity of Pt/AC was increased. It was found that the amount increase of oxygen surface groups in the AC support surface could improve the activity of Pt/AC.In the ion exchange unit, the adsorption properties of ion exchange resins for acetic acid were investigated, and the result showed that the ion exchange capacity of IRA67 resin was higher than others in adsorbing acetic acid. The acetic acid, byproduct of ethanol catalytic oxidation, could be purified efficiently by absorbing of IRA67. The adsorption reaction of IRA67 was a exothermic process. The adsorption isotherm of IRA67 was in accordance with the H3 adsorption isotherm, and the saturated ion exchange capacity of IRA67 was 75mg·g-1.In the disinfection unit, four kinds of iodinated resions were used in disinfecting the humidity condensate and the disinfection capacity, disinfection mechanism and disinfection stability of iodinated resions were investigated. The result indicated that 202 iodinated resion could kill the colon bacillus efficiently when the contact time was 10 seconds, and the bacteriological water quality objective of humidity condensate disinfected by 202 iodinated resion could meet the drinking water standard and the iodine concentration in effluent was below 2mg·L-1. The 202 iodinated resion could disinfection steadily when the pH was 4-8, the temperature was below 50℃.A reactor for treating humidity condensate was studied, which included a composite technology of wet oxidation, ion exchange and disinfection. The treatment efficency and stability of the reactor were investigated. The result showed that the concentration of ethanol, acetic acid and colon bacillus in the effluent of the reactor could meer the drinking water standard when the flux rate was 5mL·min-1 and membrane aeration pressure was 5kPa. The reactor exhibited good running stability and reliability during continuous operation.
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