Heather Willauer

Willauer attended Berry College in Georgia, graduating with a bachelor's degree in chemistry in 1996.[1] In mid-1999 she participated in the 11th International Conference on Partitioning in Aqueous Two-Phase Systems, held in Gulf Shores, Alabama.[2] In 2002, she earned a doctorate in analytical chemistry from the University of Alabama, writing her thesis on "Fundamentals of phase behavior and solute partitioning in ABS and applications to the paper industry," the "ABS" an abbreviation for "aqueous biphasic systems".[3] She began working with the NRL as an associate, then in 2004 she advanced to the position of research chemist.[1]

Willauer started researching biphasic systems and phase transitions after graduating from Berry College. In 1998 she studied aqueous biphasic systems (ABS) for the potential of recapturing valuable dyes from textile manufacturing effluent. She investigated ions and catalysts.[4]

Willauer at the NRL

In the 2000s, Willauer began studying methods for extracting CO₂ and H₂ from seawater, for the purpose of reacting these molecules into hydrocarbons by using the Fischer–Tropsch process.[5] She also investigated modified iron (Fe) catalysts and studied zeolite (nanoporous aluminosilicate) catalyst supports for recombining these molecules into jet fuel.

Previous studies had concluded that CO₂, under the form of the bicarbonate anion (HCO₃^–) dominant (96% mole fraction) in the seawater inorganic carbon species could not be economically removed from seawater.[6] However, by acidifying seawater by means of an adapted electrolysis cell with cation permeable membranes (dubbed a three-chambered electrochemical acidification cell),[7] it is possible to economically convert HCO₃^– into CO₂ at a pH lower than 6 and to increase the extraction yield. In January 2011, the NRL installed a prototype of seawater electrolysis cell at Naval Air Station Key West in Florida.[8]

In 2017, Willauer et al. were granted a patent for a CO₂ extraction device from seawater, in the form of an electrolytic-cation exchange module (E-CEM). The E-CEM is seen as a "key step" in the production of synthetic fuel from seawater. Other researchers named in the patent are Felice DiMascio, Dennis R. Hardy, Jeffrey Baldwin, Matthew Bradley, James Morris, Ramagopal Ananth and Frederick W. Williams.[9]

Willauer et al. (2012) estimated that jet fuel could be synthesized from seawater in quantities up to 100,000 US gal (380,000 L) per day, at a cost of three to six U.S. dollars per gallon.[10][11][7] Willauer et al. (2014) showed that the Fischer-Tropsch catalyst could be modified to synthesize various fuels such as methanol and natural gas, as well as the olefins that can be used as the building blocks for jet fuel.

Willauer et al. calculated that about 23,000 US gal (87,000 L) of seawater must be driven through the process to obtain the quantities of hydrogen and CO₂ necessary to synthesize one gallon of jet fuel.

Seawater was chosen because it contains 140 times more CO₂ by volume than the atmosphere, and conventional water electrolysis also yields H₂. The equipment for processing seawater is much smaller than that for processing air. Willauer considered that seawater was the "best option" for a source of synthetic jet fuel.[12][13] By April 2014, the Willauer's team had not yet made fuel to the quality standard required for military jets,[14][15] but they were able in September 2013 to use the fuel to fly a radio-controlled model airplane powered by a common two-stroke internal combustion engine.[8]

Because the process requires a considerable input of electrical energy[11] (~ 250 MW electricity mainly for the H₂ production by water electrolysis and also to a lesser extent for the CO₂ recovery from seawater),[11] it cannot be performed on a large ship, even on a nuclear aircraft-carrier. The installations processing seawater to obtain H₂ and CO₂ (in fact CO), the two essential ingredients necessary for the Fischer–Tropsch process, must be constructed on-shore, close to the sea, on islands in strategic remote locations (e.g., Hawai, Guam, Diego-Garcia) and powered by a nuclear reactor, or by ocean thermal energy conversion (OTEC).