Seawater-based one-pot ionic liquid pretreatment of sorghum for jet fuel production

Most solvent-based lignocellulosic pretreatment technologies require large amounts of freshwater, which competes with municipal/agricultural uses and can significantly influence the operating cost of a biorefinery. Seawater and other brackish water are abundant and have no competitive human uses, therefore are potentially a better water source to use in a biorefinery than freshwater. We found that performing pretreatment and saccharification using the biocompatible ionic liquid (IL) cholinium lysinate diluted in seawater in a consolidated single unit operation or “one-pot” process configuration results in comparable glucose and xylose yields relative to freshwater. Next, the sugars in seawater hydrolysates were converted into the potential jet fuel molecule prespatane by an engineered strain of Rhodosporidium toruloides. This study illustrates that seawater can effectively displace freshwater when used in a one-pot biomass pretreatment, deconstruction, and conversion process using a biocompatible IL and a salt-tolerant microorganism. © 2020