Session: Research Posters

Paper Number: 120257

120257 - Minerals From Seawater– a Case of Blue Economy for the Gulf of Mexico 

The Gulf of Mexico is well known for its enormous offshore oil reserves and production and wind energy resources. Also of abundance are the minerals in the seawater. A recent study found that cobalt, a material particularly important for the growing EV market, could be extracted to account for around 27% of the nation’s cobalt consumption from retrofitting 76 unused oil platforms in the Gulf of Mexico. The cobalt’s molar concentration in seawater is 1.7 x 10^-9. On a molar concentration basis, the top seven elements are chlorine (0.5361), sodium (0.4591), magnesium (0.0523), sulfur (0.0276), calcium (0.0100), potassium (0.0097), and bromine (0.0008). Seawater also is rich in carbon. The mole fraction of organic carbon is 0.00025 and that of inorganic carbon is 0.0023. The cobalt extraction study suggests that there exists a tremendous opportunity to retrofit unused oil platforms in the Gulf of Mexico for the blue economy and CO₂ capture. However, because of the low concentrations of minerals in seawater, it takes a large volume to extract a small amount of the minerals. For example, with a natural concentration of 0.178 mg/l (or molar concentration of 0.000015), it takes 5,800-ton seawater to extract 1 kg of lithium and almost 30 times more seawater for nickel (its natural concentration is 0.0066 mg/l). This paper presents a literature review of methods to extract from seawater strategic minerals of lithium, cobalt, nickel, and magnesium for the automotive industry, particularly important to the supply chain of EV manufacturing. They are thermal processes or solar-thermal processes for the Gulf of Mexico, to increase the mineral concentrations by vaporing water from seawater and followed by chemical and electrochemical processes to precipitate the target mineral in high purity. A novel method based on membrane technology was presented lately to extract lithium. The method is a combination of an anion exchange membrane (AEM) and a glass-type lithium membrane to precipitate lithium from seawater. This paper will also present a free-and-thaw process developed in Chen’s lab that fabricates AEM from PVA (polyvinyl alcohol) soaked with untreated seawater taken from the Gulf of Mexico. The AEM was tested with success in a metal-air electrochemical cell using magnesium or aluminum (molar concentration in seawater 7.0x10^-5) as the anode and copper (molar concentration in seawater 1.4 x 10^-6) as the cathode. The electrochemical cell was able to run continuously for 24 hours. With further development of offshore wind turbines and retrofitting of unused oil platforms, the Gulf of Mexico will become an important contributor to the blue economy and the energy mix to meet the nation’s carbon-neutral goal.

Presenting Author: Lea Der Chen Texas A&M University – Corpus Christi

Presenting Author Biography: Dr. Lea-Der (LD) Chen is currently a Professor and Associate Dean for Research of the College of Engineering at Texas A&M University–Corpus Christi. Prior to joining A&M – Corpus Christi in July 2010, he was with the University of Iowa, holding professorial positions as well as department chair (Department Executive Officer) and center director (National Advanced Driving Simulator) positions. Chen earned his baccalaureate degree in mechanical engineering from National Taiwan University (Taipei, Taiwan), and his master's and Ph.D. degrees from the Pennsylvania State University (University Park, Pennsylvania). Upon receiving his Ph.D. degree, Chen was appointed a Research Associate at Penn State’s Applied Research Laboratory and held a non-tenure track assistant professor appointment in the Department of Mechanical Engineering. Chen also had an IPA appointment at Air Force Research Lab (WPAFB, Ohio) conducting research in jet diffusion flames. His research has been funded by NSF, AFOSR, ONR, NASA, TARDEC, ARDEC, ConocoPhillips, Honda R&D, GM, Cummins Inc., and Deere & Co. Chen’s NASA-funded research included a glovebox investigation onboard the US Space Shuttle Columbia STS-87/USMP-4 Mission in November/December 1997. He has authored/co-authored more than 160 technical publications and is a co-inventor of 2 patents. Chen’s current research is in the areas of energy and coastal resilience.

Chen is a life member of ASME, a senior member of AIAA, and a member of ASEE and the Combustion Institute. He currently serves as Vice Chair of the ASME Aerospace Division.

Authors:

Lea Der Chen Texas A&M University – Corpus Christi
Jeffrey Zhu The University of Texas at Austin