(403f) Advances in Fast Hydrothermal Liquefaction of Microalgae

A majority of the liquid petroleum consumed globally each year is directed to the transportation sector. The combustion of petroleum fuels releases carbon dioxide into the atmosphere, contributing to global climate change and other environmental problems. To reduce the negative impact of transportation on the environment, the development and implementation of liquid fuels with reduced life cycle carbon dioxide emissions is important. The production of biofuels from algae may yield liquid fuels with fewer carbon dioxide emissions than their petroleum alternatives, especially when processed such that energy-intensive drying steps are avoided. Fast hydrothermal liquefaction (FHTL) is a process that relies on the properties of liquid water at high temperature and pressure to convert biomass into energy-dense biocrude oil in 60 seconds. Since FHTL was recently discovered, a great deal about this biomass conversion process is not yet known.

This presentation describes two approaches for understanding FHTL. First, we used Fourier Transform Ion Cyclotron Resonance Mass Spectrometry (FT-ICR MS) to characterize the aqueous phase and biocrude products of FHTL and isothermal hydrothermal liquefaction (HTL), a better studied biomass conversion process. The ultra-high resolution of FT-ICR MS allowed for the identification of individual compounds by their molecular formulas. This detailed level of characterization provides a great deal of information about the FHTL and HTL processes. Second, we performed empirical kinetic modeling to develop a single model that describes both FHTL and HTL processes. Taken together, these approaches provide information of paramount importance to the scale-up and implementation of the FHTL biomass conversion process.