Scaleable, High Efficiency Microchannel Sabatier Reactor

An innovative Microchannel Sabatier Reactor System has been developed for the efficient production of oxygen (as water) and methane from carbon dioxide (CO2), a valuable in situ resource available in the atmosphere or as frozen deposits on Mars and other Near Earth Objects, which will help mitigate mission resupply logistics and risk. The Sabatier reaction benefits from inherently superior micro reactor heat and mass transfer characteristics compared to conventional reactor designs. Significantly, graded temperature micro reactors can readily be configured in a parallel arrangement to vastly improve conversion efficiencies. Process scale-up is easily achieved by increasing the number of equivalent, parallel micro reactors. High conversion rates require the deposition of a highly active, supported catalyst layer onto microchannel walls that is characterized by enhanced surface area, appropriate adsorption characteristics, and catalyst effectiveness factor. A core focus of the research effort was the design of a MSRS that optimizes residence time, thermal recovery, and most importantly, the achievement of near equilibrium reaction product composition at low temperature. A three stage reactor consisting of a supported noble metal catalyst on stainless steel tubing and sequentially heated to 365, 294, and 234 degrees centigrade demonstrated 96% single pass conversion efficiencies of CO2 to methane for an influent gas composition of 4:1 H2:CO2.