ARPA-E is investigating the feasibility of extracting critical minerals, specifically Rare Earth Elements (REEs) critical for the production of electric motors and generators, and high-value Platinum Group Metals (PGMs), from macroalgae cultivated and/or harvested within the U.S. Exclusive Economic Zone (EEZ).

The targeted outcomes of this topic are:

  1. An understanding of what environmental, temporal and ecological factors influence the PGM/REE metal content of ocean-grown macroalgae;
  2. Identification of the mechanism of biological metal absorption and hyperaccumulation by ocean macroalgal biomass, including the maximum capacity and absorption rate thereof, variability and location of mineral concentration within the macroalgal holobiont, variation among species, impact of harvesting strategies, and underlying cellular and molecular mechanisms;
  3. Development of methods to extract critical minerals from the macroalgae at high output purities that can dovetail with existing and nascent macroalgal valorization streams developed for the other components of macroalgae such as carbon compounds, macroand micro-nutrients, utilizing existing waste streams from seaweed biorefineries; and
  4. A techno-economic analysis of these methods, considering the sensitivity to the inputs investigated in items (1), (2) or (3).

Program Director(s):

Dr. Simon Freeman