Vacuum-Regenerable Sorbent for NASA’s Exploration Portable Life Support System

In this Phase II SBIR proposal, XploSafe will build on its Phase I work investigating the use of nanoporous silica as a sorbent for NASAs Trace Contamination Control System within the Exploration Portable Life Support System (xPLSS). Phase I results demonstrated the feasibility of using nanoporous silica as a vacuum regenerable sorbent for integration into NASAs xPLSS. It was shown that this sorbent has significant advantages due to its high capacity for ammonia and other trace contaminants. It also has the ability to be vacuum regenerated for potential future integration into the swing-bed structures in the xPLSS. For Phase II, XploSafe will further investigate physical properties of the sorbent as it related to specific NASA requirements, expand experimental measurements of the capacity and kinetics for the sorption of potential trace contaminants and their combinations to 18 potential target analytes, and develop and verify a prototype for integration in the xPLSS. The combination of the nanoporous silica and a functionalized material will be considered to ensure complete elimination of the wide range of contaminants. For the prototype, two different versions will be examined, one in which the sorbent will be contained in microporous tubes, preventing all possibility of dust generation at the expense of kinetics; and a second more traditional design based on direct flow through the sorbent filter material. At a minimum, an early prototype is envisioned at the midpoint of the Phase II contract with the final version delivered at the end of the project NASA is poised to make the next step out into the solar system with Human Exploration of the Moon and beyond. Highly reliable space suits are one of the keys to the success of this effort. The development is underway for the next generation of spacesuit called the Extra-Vehicular Mobility Unit (xEMU). The Exploration Portable Life Support Subsystem (xPLSS) is a component of the xEMU. The xPLSS is tasked with maintaining a breathable atmosphere free of harmful pollutants. Within the xPLSS, the Trace Contamination Control System (TCC) is a sorbent-based purification system which removes contaminants present in the ventilation system. The proposed innovation is a new vacuum-regenerable sorbent which can efficiently remove accumulated contaminants which can pose severe health threat to the crewmembers. The proposed research aims to have major positive impact on the logistics of future space missions by replacing the current non-regenerable sorbent with a vacuum-regenerable sorbent. Success in the completion of Phase I has provided clear direction towards the development and operational evaluation of prototypes during Phase II. The future objectives and tasks are to develop and deliver a prototype of a new Trace Contamination Control System that can be directly integrated into the Exploration Portable Life Support Subsystem (xPLSS). The objectives are divided into three groups. The first set of objectives include (1) Develop a sampling system using separation followed by mass spectroscopy to quantify the contaminants, and (2) Develop a gas recirculating system with controlled contaminant levels. The second set of objectives is to (3) optimize sorbent synthesis, including possible functionalization or modification with another compliant sorbate, (4) Conduct breakthrough experiments to for all 18 target analytes to quantify capacity, kinetics and regeneration, (5) Conduct breakthrough experiments for gas mixtures and (6) develop a breakthrough matrix to assess competition between analytes. The last set of objectives will focus on the development and evaluation of prototypes, (7) evaluate removal of target analyte vapors representative loop of the xPLSS, (8) conduct vacuum regeneration as concept for potential future integration into the swing-bed structures in the xPLSS, (9) design, test and fabricate prototypes of sorbent holder for system-level testing
Benefits: Successful development of the proposed technology will advance the state of the art in trace contamination control. As a part the Exploration Portable Life Support System (xPLSS) and the Exploration Extra-vehicular Mobility Unit (xEMU) units, the new sorbent technology will advance the viability of NASA's crewed deep space exploration objectives Success in developing more effective and efficient filtration media could provide a significant enhancement in the protection of public health and the environment. This new filter media will serve a wide variety of markets as high efficiency particulate air filters (HEPA) in HVAC systems. Applications range from clean rooms, labs, industrial manufacturers, coal and ore mining facilities etc.