Born Global Internship
Sustainable Water Filtration and Battery Recycling Research
Sustainable Water Filtration and Battery Recycling Research
As an Engineering Intern at the Born Global Foundation I designed and built a custom water filtration system to explore the use of biochar and other fine-particle filters for desalinating water. The project aimed to test whether these low-cost, sustainable materials could effectively remove salts from solution. While the immediate goal was to evaluate filtration performance and pH/conductivity changes, the long-term vision connects this process to battery recycling. Once the technology advances, recovered salts could be refined and repurposed in the production of recycled lithium-ion batteries. This work combined literature review, system design, and hands-on experimentation, bridging environmental sustainability with emerging clean energy technology.
The rapid rise of electric vehicles, renewable energy systems, and consumer electronics has driven an unprecedented demand for lithium-ion batteries (LIBs). While LIBs are highly efficient and durable, the lithium required for their production is increasingly constrained by limited mining capacity and low recycling rates currently estimated at only 1–5%. Closed-loop recycling, where recovered materials are reintroduced into new batteries, requires lithium purity levels above 99.5%, a benchmark that most existing recycling processes fail to meet.
One potential pathway to meet these purity requirements is through advanced filtration systems capable of isolating high-quality battery salts from various sources, including brines and recycled battery leachates. Filtration technologies such as reverse osmosis, ultrafiltration, and nanofiltration offer scalable options, while adsorption processes using specialized materials can target specific ions based on charge and size. In this project, I explored whether a combination of biochar—a highly porous, carbon-rich, renewable adsorbent and nanofiltration membranes could provide an affordable, effective method for desalinating water. The recovered salts, with further refinement, could eventually be repurposed for battery production as recycling technology advances.
I designed and assembled a lab-scale filtration system to test the viability of using biochar and other fine-particle filters for salt removal. The setup began with a saltwater solution of known concentration, pH, and conductivity, which was passed through two sequential filtration stages. The first stage used a biochar bed to adsorb ions based on pH-driven surface charge interactions, while the second stage employed a commercially available nanofiltration membrane to further separate dissolved salts by size and charge exclusion.
Throughout the process, I measured the filtrate's pH and conductivity to quantify salt removal efficiency. Biochar was selected for its sustainability, low cost, and potential for large-scale use, while nanofiltration membranes were chosen for their proven ability to reject dissolved salts without extensive chemical processing. The experiment served as a proof-of-concept for integrating adsorption and nanofiltration in a low-cost desalination system, with a future application in high-purity salt recovery for sustainable battery recycling.