EAPSI:Effects of Crystal Structure on Metal Uptake in Manganese-oOxides

Ulrich Sarah A, Blacksburg VA

Investigators

Abstract

Manganese (Mn) oxides are unique minerals that have widely varying crystal structures, including layered and tunnel structures that can be used for many purposes. While Mn-oxides are found throughout nature, crystals that grow in contact with fungus or bacteria are more effective at metal recovery than Mn-oxides formed inorganically. In addition, such a process is less chemically intensive than other inorganic syntheses. This project will utilize a Mn-oxidizing fungus to grow birnessite, a layered Mn-oxide, in order to obtain lithium from seawater. Lithium is vitally important for its use in batteries, however, there are very few commercially viable, land-based lithium deposits. The project will be conducted under the mentorship of Dr. Keiko Sasaki at Kyushu University in Fukuoka, Japan. Dr. Sasaki is an expert in the use of biogeochemistry for mineral processing and environmental resource recovery. Previous work has shown that heating birnessite in the presence of LiCl forms a lithium manganese oxide (LMO) "sieve" that can be used to retrieve lithium from seawater. Lithium recovery capacity is dependent on the temperature to which the LMO was initially heated. In this project, LMOs will be added to seawater containing low concentrations of lithium, in order to measure lithium uptake. In addition, Transmission Electron Microscope (TEM) will be utilized to investigate the changes to crystal structure that occur with heating, and how these structural shifts either assist or hinder lithium uptake. These data will be acquired with the assistance of Dr. Satoshi Hata using Kyushu University?s rare, low voltage, high resolution TEM. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science (JSPS).