Integrated Mars In Situ Propellant Production System

Pioneer Astronautics has developed a system that harvests CO2 from a simulated Martian atmosphere and reacts it with H-2 into rocket propellant at a rate of 1 kg/day. A prototype system operated autonomously for 5 consecutive days, during which it maintained a 100% conversion rate (to detectable limits) of CO2 and H-2 into products, maintaining a constant O-2:CH4 ratio in the product stream with only minor adjustments. The integrated Mars in situ propellant production system (IMISPPS) uses a mixed catalyst bed to conduct the Sabatier methanation reaction and the reverse water gas shift in a single reactor. A recycle loop makes performance resistant to operational changes, with product ratios stable regardless of reactor temperature changes of as much as 100 degrees C. An optimized IMISPPS is projected to produce 1 kg/day of O-2: CH4 propellant and have a mass of 50 kg with a methane purity of 98+% while consuming 700 W of electrical power. With hydrogen from Earth, the system demonstrates a mass leverage of 18: 1 in useful rocket propellant produced on Mars compared with imported feedstock. DOI:10.1061/(ASCE)AS.1943-5525.0000201. (C) 2013 American Society of Civil Engineers.