Research mission: To understand and predict metal behavior at the mineral-water interface to inform resource recovery strategies, understand metal mobility in natural environments, design contaminant removal approaches, and assess implications for human health.

Mineral surfaces control metal (Mn+) mobility and availability

If Mn+ is a valuable resource, ...

How to design and optimize recovery from deposits?
What retention mechanisms control the formation of economically viable deposits?

If Mn+ is a contaminant, ....

What are its fate and transport in the environment?
Will it remain adsorbed to mineral surfaces or become dissolved, and what does it mean for bioavailability?
Can effective adsorbents be designed for their removal?

My research strategy is to combine experiments, modeling, analytical measurements, and my background in aqueous chemistry and environmental engineering to translate interfacial geochemistry into applications related to resource recovery, drinking water quality, and environmental management.

Projects

REE adsorption to minerals

Rare earth elements (REEs) are critical for modern electronics, sustainable energy production, and medicine. Ion-adsorption deposits, one of the world’s major REE sources, contain kaolinite and gibbsite, whose mineral surfaces strongly influence REE mobility. This project systematically investigates the effects of water chemistry on REE adsorption to kaolinite and gibbsite by combining adsorption experiments, surface complexation modeling, and spectroscopic investigations. The work improves the understanding and prediction of REE behavior in clay-rich deposits, thereby advancing current knowledge of REE geochemical cycling.

Dissolution of iron oxides and release of trace elements

Iron oxides are widespread in weathering environments and can host structurally incorporated trace elements, including heavy REEs. The stability and dissolution of these minerals influence REE mobility within ion-adsorption deposits. This project investigated the kinetics and stoichiometry of the REE release from goethite during ligand-promoted dissolution in the presence of oxalate and citrate. The work combined batch and flow-through dissolution experiments with dissolution rate modeling to improve understanding of the behavior and mobility of incorporated REEs in ion-adsorption deposits.

Soil and human health

Metals and metalloids such as Pb, As, and Cd are toxic and carcinogenic, yet they are widespread in urban soils. The public may be exposed to these elements through accidental ingestion of soil particles or consumption of produce grown in urban garden soils. A series of projects throughout my career has aimed to quantify exposure to metals and metalloids in soils and waters and evaluate associated risks using statistical analysis of environmental data. Assessing environmental exposure and associated risks is important for informing environmental policy and guiding environmental management efforts.