Description: Supporting human life on long-tern space exploration missions, such as manned missions to the surface of Mars, require sustainable resource utilization with minimal support from Earth. In response to this need, NASA's in-situ resource utilization (ISRU) mission was put in place to provide a sustainable infrastructure for long-tern missions, such as exploration of extraterrestrial planets. One particular resource available on Mars is atmospheric carbon dioxide (CO2). CO2 makes up 95% of the atmosphere, providing an abundant resource for human explorers to take advantage of. For instance, CO2 can be electrochemically reduced into a variety of compounds, including polyethylene. Polyethylene is a widely used plastic, for manufacturing containers, tubing, sealants, and more. In Phase I, Faraday and UTEP will develop an electrochemical reactor capable of converting atmospheric carbon dioxide into polyethylene at conditions commonly experienced on the Martian surface, such as low temperatures (-65°C average on Martian surface) and low pressures (0.0065 bar). Optimization of polyethylene production will be performed through modifying the reactor design and the electrodes, with the goal of producing polyethylene with high selectivity (>50%) with a low energy requirement for production of polyethylene (0.034 g polyethylene per watt-hour). Phase I will include a critical risk assessment for using naturally occurring perchlorate salts, which are found in water on Mars, as the electrolyte in the electrochemical reactor. Alignment of this technology with future NASA and commercial missions to Mars is critical for successful integration, and with the help of our team, we will assess safety and system robustness metrics required for Phase II and beyond. In Phase II, we will work to scale up the production of polyethylene, while establishing the ability to process CO2 from atmospheric conditions similar to Mars.

Benefits: The ability to produce high value manufacturing materials at the landing site of manned missions to exoplanets would save a significant amount of mass to carry from Earth. The proposed technology would support lower launch masses required for escaping Earth's gravity well and long-term activities on the Martian surface. Polyethylene is a versatile plastic, and will be able to be used in nearly every system found on manned missions to Mars, including life support, personal protective equipment, structures, and food and water storage. Specifically, polyethylene sheets can be used to construct greenhouses for growing crops on the Martian surface, and as a vapor barrier during construction. Additionally, because polyethylene has a very low glass transition temperature when compared to other plastics, it can be used as a flexible sealant to create air and water proof seals. Polyethylene is also a hydrogen-dense material, which means it is effective at blocking radiation. This will be beneficial for NASA, as the amount of radiation on the surface of Mars is much higher than the surface of Earth. Sheets of polyethylene can be used to protect both astronauts while living on the Martian surface, and to protect sensitive electronic equipment that may be damaged by higher doses of radiation. In addition to the production of polyethylene, the proposed technology will also produce breathable oxygen gas. While the main objective of this technology will not be the production of oxygen, the gas produced during the polyethylene production will be breathable. This can be used to increase the capacity of life-support systems for the astronauts, or as an oxidant for combustion of fuels to launch rockets from the surface of Mars.The potential terrestrial customer could be involved in a variety of industries. Polyethylene is currently the most widely used plastic in the world, where the material can be used in clear food wrap, shopping bags, detergent bottles, and automobile fuel tanks. One of the most common uses of polyethylene is for storage of food and liquids. These containers benefit from polyethylene, as the plastic is lightweight, yet durable, allowing for a reliable container that will not break down or fail. An additional benefit of production of polyethylene from atmospheric CO2 is the avoidance of foreign-sourced petroleum to produce the material. The technology developed here can be paired with large-volume CO2 producing systems, such as electricity production of cement manufacturing, where the CO2 can be captured easily and electrochemically converted into polyethylene. Polyethylene is used widely in coal power plants for transportation of hot and cold water. Polyethylene is also used in cement manufacturing plants as molds for specifically shaped cement parts. The technology developed here will be able to be applied as a point-source CO2 capture device to produce polyethylene in an environmentally friendly manner, while also not requiring the use of foreign-source petroleum products.