(175b) Mars Regolith- Hydrochar Complex Synthesis with Water Retention Application

With the advancement of technology and the determination of humanity to inhabit Mars, the necessity of finding sustainable ways to cultivate and produce food, in deep space, has risen at an alarming rate. With the steep cost of transportation between Earth and Mars, NASA has emphasized the importance of utilizing the natural resources found on Mars. Research has found that hydrochars, biomass that has undergone the application of hydrothermal carbonization (HTC), is key in improving the water retention capacity of natural resources. The purpose of this study was to further the initiative through the development of Mars Regolith-Porous Carbon Complex (MRPCC) in order to enhance the water retention properties of Mars regolith via the utilization of hydrochars. Loblolly pine was selected as the biomass and was combined with Mars regolith (0, 5, 10, 25, 50 %w/w) before being chemically activated, with KOH at a 4:1 ratio respectively, at 800 °C for 2 hours to synthesize MRPCC. The resulting MRPCC was then characterized using N₂ adsorption–desorption for surface porosity quantification, scanning electron microscopy for morphology appearance analysis, X-ray powder diffraction for crystallinity analysis, proximate and ultimate analysis for detailed chemical composition analysis, and ion chromatography to determine the nutrient adsorption capacity. Additionally, the MRPCC's ability to hold water was tested by first saturating it with water and then slowly stirring it until excess water was visible. Results show that MRPCC's water retention increased by 2% when, compared to that of the pure Mars regolith, suggests that the addition of porous, organic material has furthered the initiative. Preliminary nutrients adsorption results have indicated that MRPCC has significant adsorption qualities, especially regarding ammonium, at 3000ppm and is expected to supersede these results at greater concentrations. With these considerations in mind, MRPCC is favorable when considering applications such as an agricultural aid, on Mars.