Synthetic Gasoline from Biomass
EPA Phase I SBIR Contract EP-D-07-028
Clean and renewable liquid fuels from biomass offer reduced net emission of CO2 and less dependence on expensive foreign oil from unreliable sources. Currently, bioethanol is used in the U.S.A. as a gasoline blend, but eventually it could replace gasoline in passenger cars. Ethanol, however, contains only two-thirds of the energy compared to gasoline on equal volume basis; and if used at high concentration, it requires retrofitting existing cars. Therefore, it could be economically and technologically advantageous to convert biomass to a hydrocarbon-based synthetic gasoline (SG) – a hydrocarbon mixture performing similarly to petroleum-derived gasoline.
Eltron is developing a new, novel biomass-derived gasoline fuel. Specifically, methanol will be converted catalytically to C5 C10 isoalkanes. Methanol could be obtained from biomass, either directly by biochemical processes or indirectly from synthesis gas (CO + H2) produced by biomass gasification. In this catalytic conversion of methanol to SG, the hydrocarbon product is free of any naphthenes and aromatics, and from heteroatom and metal impurities. Co-produced isobutane could be reacted separately to provide isooctane and/or isononane, or ETBE, as additional fuel liquid with very high octane. The overall SG product could be superior to conventional gasoline, with higher ignition and combustion efficiencies, less toxicity and less emission of pollutants such as CO and THC. At a methanol cost of ~35˘ per gallon, this SG could be produced at about half the current price of gasoline.
Eltron’s research aims at (1) showing feasibility and substantiating preliminary results, and (2) preparing simulated SG samples of relevant isoalkane compositions and analyzing them for their “gasoline specs,” to compare them with conventional gasoline. In subsequent research, we will construct and operate a bench-scale methanol conversion apparatus to afford a full technical feasibility study with a goal of implementing a pilot plant engineering design effort, possibly through partnership with a biomass processing business and/or an oil refining company. In further research and development a demonstration scale facility will be constructed to produce fuels for large-scale engine testing.