Description: We propose to design, model, build, and test a novel flash cracking reactor to convert plastic waste, and potentially other unconventional hydrocarbon feedstocks, into tunable molecular weight fuels. The innovative reactor technology "flashes off" desired hydrocarbon products as they form, thus preventing the over-cracking of the polymers into more volatile hydrocarbons. This leads to improved selectivity for low vapor-pressure hydrocarbons, which are easier to store as fuel in large quantities at low pressures, as well as tunable molecular-weight products for multiple applications. Our design approach in Phase I will use a combination of heat/mass transfer modeling with pyrolytic kinetics modeling for PE and PP, which will be used as a model system for waste plastic pyrolysis. We will first demonstrate, using our pyrolytic model, that the hydrocarbon product distribution can be modified and tailored by varying the reactor and condenser temperatures, nitrogen gas flow rate, and system pressure. We will also build and test the reactor system based on our model results. Controlling the product distribution of a flash cracking reactor while minimizing parasitic losses will be the primary challenge during the Phase I effort.

Benefits: Other government agencies can also benefit from the proposed technology. The US Air Force is breaking ground on pilot-scale FT jet fuel production facilities, and our technology is equally applicable to the cracking of FT waxes. Other military applications include in-situ generation of diesel-like fuel to operate the DoD's portable diesel-engine electric generators. Electric generators are usually the largest consumer of fuel on the battlefield, and this fuel often must be trucked in at a high "fully burdened" prices that can be in excess of $100/gallon. The proposed technology can of course also be used for commercial conversion of plastic waste into liquid fuels, as companies like Envion and Global Finest have shown with similar technologies. This is likely to be our break-in market, as there is a great need to make use of the used plastic that is currently being incinerated or kept in landfills for decades. The proposed technology can later be adapted for upgrading unconventional petroleum reserves, including tar sands, oil shale, and heavy crude. Unconventional petroleum reserves are an important component of world petroleum reserves, and innovative upgrading technologies will be required for economically converting them into useful transportation fuels.

The target NASA application for the proposed technology is in-situ liquid fuel production in the moon using waste plastics and other organic materials. The purpose of NASA's effort for In-Situ Resource Utilization (ISRU) is to harness and utilize resources at the site of exploration to create products and services, which can enable and significantly reduce the mass, cost, and risk of near-term and long-term space exploration. Such capabilities are considered extremely important to human expeditions to Mars which, because of the distances involved, would be much longer missions entailing a minimum of 500 days spent on the planet's surface. We anticipate that the proposed system can be used during lunar days, in conjunction with solar heating and excess solar-electrical power, to generate fuel that can be stored and used during lunar nights. Lunar nights can last up to 334 hours, and storage of electrical energy in batteries and flywheels for use during lunar nights is not practical even with the most advanced electrical storage technologies available today. Liquid fuel obtained from plastic waste will inherently be low in sulfur and can be readily used in solid-oxide fuel cells (SOFCs) for electrical power generation at night. This fuel can also be used to power generators, heaters, and similar appliances needed in space missions.