In-Situ Resource Utilization for Electrochemical Generation of Hydrogen Peroxide for Disinfection

Technological innovations are essential to enable energy-efficient maintenance of closed air, water, and waste systems for interplanetary travel with limited resupply options and microgravity living conditions. One particular need for the interstellar travel community is disinfection to meet personal hygiene requirements. At present, surface disinfection in space vehicles is accomplished through the use of pre-packaged, disposable, wetted wipes, which represent an appreciable carry-along mass and disposal burden. Therefore, next-generation system should use onboard utilities to create on demand disinfectants thereby reducing the astronaut’s dependence on earth based supplies and further eliminating storage and disposable problems. Within this context, we are demonstrating a technology to generate disinfectants that can neutralize or eliminate many of the contaminants while improving system maintenance and disinfection. Specifically, we are exploring an electrochemical system for generating hydrogen peroxide, a well-established disinfectant with non-toxic decomposition products (viz., oxygen and water), that is safe enough for human contact to be sold commercially as a 3 w/w% solution. This concept is founded on the electrochemical reduction of oxygen to hydrogen peroxide using readily available on-board supplies of oxygen and water. Initial trials confirmed that the developed system utilizing oxygen and RO water can generate >1 w/w% peroxide concentration. The proposed hydrogen peroxide generation system offers a more economical and practical alternative, with the disinfectant solution being generated on demand and in-situ; and applied to reusable cloths, reducing both the carried and disposed mass associated with the disinfection process. A zero gravity flight test is scheduled for March 2019 to validate the technology in microgravity environments. The specific application of interest to this program is crew contact surfaces in space vehicles, but this approach could be utilized for waste water disinfection, heat exchanger biofouling remediation, and laundry applications. Acknowledgements: Financial support of NASA Contracts No. NNX16CA43P and NNX17CJ12C are acknowledged.