The Gene and Linda Voiland School of Chemical Engineering and Bioengineering is hosting a seminar presented by Adan Schafer Medina, Ph.D. Student, Voiland School of Chemical Engineering and Bioengineering, Washington State University, Jan. 29, at 4:10 p.m. in ADBF 1002/FLOYD 256 (Tri-Cities).
Adan Schafer Medina is from Pasco, Washington and earned his B.S. in Chemical Engineering from Washington State University (WSU) in 2013. Mr. Schafer Medina began his Ph.D. in the lab of Professor Haluk Beyenal in the fall of the same year, where he was awarded the Achievement Rewards for College Scientists Scholarship and became part of the 2013 cohort for the National Institutes of Health (NIH) Protein Biotechnology Traineeship Program, which provided two years of direct funding. In 2015, Mr. Schafer Medina was awarded the National Science Foundation East Asia and Pacific Islander Summer Institutes fellowship. Mr. Schafer Medina was awarded top poster presentation at the Interagency Technical Nuclear Forensics Program Review (ITNFPR) in the summer of 2017.
Determining the pre-concentration mechanism for trivalent lanthanides on polarized electrodes
The rapid preconcentration of lanthanides in aqueous solution is of interest to enable follow-on analysis of nuclear fallout samples for the purposes of technical nuclear forensics. The large negative overpotentials required for the reduction of the lanthanides (Ln’s) along with their member’s instability in aqueous solutions has limited electrode-assisted preconcentration efforts to Hg amalgams and carbon paste electrodes. However, the mechanism of preconcentration for these methods has yet to be determined. Previous work has shown that the surface pH at the electrode surface will deviate significantly from the bulk, even in buffered solutions, when the electrode is polarized beyond the stability limits of water. This work uses the electrochemical quartz crystal microbalance (eQCM) to monitor the film formation of lanthanum on a polarized electrode surface via gravimetric analysis. The electrodes coated with lanthanum species were analyzed with XPS to determine their chemical state and confirm the presence of a lanthanum deposit. Ligand-assisted preconcentration schemes were also investigated.
