Characterizing Critical Metal Binding in Acid Mine Drainage Treatment Solids

The National Energy Technology Laboratory's (NETL's) record of success has been built on understanding the future of energy and the technologies required to make that future possible. We’ve long touted our success in developing the technologies that took on acid rain in the 1970s and mercury in the early 2000s. More recently, NETL has a leading role in President Biden’s ambitious climate goals, including a carbon emission-free power sector by 2035 and a net-zero economy by 2050.

Program Goals

The NETL Postgraduate Research Program (PGRP) is a high-intensity program designed to identify recent Master’s and Doctoral graduates of high promise and to foster advanced skill development. It allows the postgraduate to systematically outline career goals and helps provide the means of achieving these goals. NETL principal investigators and leads serve as mentors to PGRP participants during the program. This interaction affords the postgraduate a unique opportunity to develop critical skills needed to become an independent professional.

The program goals include providing the opportunity to participants to:

• Develop skills and knowledge in their field of study
• Engage with new areas of basic and applied research
• Network with world-class scientists
• Exchange ideas and skills with the Laboratory community
• Use state-of-the-art equipment
• Contribute to answers for today's pressing scientific questions
• Collaborate with the broader scientific and technical communities

Project Details

Through the Oak Ridge Institute for Science and Education (ORISE), this posting seeks a post-Doctoral or post-Master's researcher to engage in projects with the Research Innovation Center (RIC) at the National Energy Technology Laboratory (NETL) in the area of Minerals Sustainability under the mentorship of Christina Lopano. This project will be hosted at the NETL Pittsburgh, PA campus. This opportunity may also be hybrid with activities taking place both on-site and off-site/virtually.

Passive (limestone) remediation beds for the treatment of acid mine drainage (AMD) in Appalachia produce stable, metal-rich oxides (Al, Mn, Fe-rich) as the acidic mine waters are passivated through limestone beds. These solids are high in critical minerals, up to 2,000 ppm REE, up to 1.2 wt% Co, Ni, Zn, and 440 ppm Li (Hedin, et al., 2019). These critical metals are found in conjunction with metal oxide rich treatment solids; however, the binding mechanisms are poorly understood. The purpose of this research would be to examine the role of sorption versus substitution in the metal oxide (MO) structures, including but not limited to Mn-oxides. This includes advanced characterization via synchrotron micro X-ray fluorescence (XRF) mapping coupled with micro-XANES (X-ray Absorption Near Edge Structure) on the regions where the REE/CM concentrations are identified. Our hypotheses are: 1) that REEs are mainly associated with Mn (or Al) -oxides via surface complexation; 2) Li/Ni/Zn are mainly associated with Mn oxides sensitive to reductive mobilization; and 3) Co is substituted into the Mn-O octahedral structure during precipitation.

The goal of this research appointment is to fully characterize Mn-rich treatment solids derived from acid mine drainage (AMD), with a particular focus on critical metal binding mechanisms. The research would focus on data analysis of cobalt and nickel soption isotherms, coupled with analysis of synchrotron x-ray absorption spectra collected on natural and lab synthesized manganese oxides. This data will be incorporated into modeling efforts and published in peer review journals.

Stipend: The selected participant will receive a monthly stipend commensurate with educational level and experience.

• Post-Master's stipends start at $3,891 per month.
• Post-Doctoral stipends start at $5,759 per month.

Deliverables: To document the effectiveness of the program, participants are required to submit a pre-appointment and post-appointment survey, as well as a reflection on their appointment experience when they renew or end their appointment. The reflection should summarize their project(s), additional activities, and overall experience. Details are provided as the appointment end date approaches.
Participants may also have the opportunity to contribute to manuscripts, journal articles, book chapters, conference presentations, posters, patents, and other publications as a part of their appointment. Such achievements should also be reported to ORISE; additional details are provided after an offer has been accepted.

The National Energy Technology Laboratory (NETL), part of the U.S. Department of Energy (DOE) national laboratory system, is owned and operated by the DOE. NETL supports the DOE mission to advance the energy security of the United States. This is an educational opportunity offered by NETL and administered by the Oak Ridge Institute for Science and Education. Participants in the program are not considered employees of NETL, DOE, the program administrator, or any other office or agency.

Qualifications

To be eligible, you must have received a Master's degree within the last three years or a Doctoral degree within the last five years; or be planning to receive a Master's degree or doctoral degree prior to the appointment start date.

The ideal candidate would have some, but not necessarily all, of the following:

Geochemistry, Environmental Chemistry coursework and skill set.

Particular familiarity with laboratory sorption experimental protocols and characterization are desired.

Experience collecting x-ray fluorescence and absorption spectra is desirable.

Geochemical modeling experience is also beneficial.