“Hydrogel Soil Amendment for Enhancing Nitrogen Fertilizer”
Jackson Stansell, S.B. ’19, engineering sciences – environmental science and engineering
Advisor: Neel Joshi, Associate Professor of Chemical and Biological Engineering
For his project in the capstone course Engineering Design Projects (ES 100), Stansell addressed the issue of nitrate leaching, which has economic and environmental costs. He designed hydrogel beads to be mixed into topsoil to capture nitrate in the early stages of the plant’s growing cycle when the soil is most vulnerable to nitrogen leaching. These beads could then later release nitrogen, relying on gravity to pull the nitrogen down towards the plant’s roots later in its growing cycle. Stansell tested different hydrogel fabrication methods, such as freeze thawing and air drying hydrogels, to optimize the nitrate adsorption and desorption kinetics. He applied an acid treatment at the end of the fabrication process to maximize the adsorption capacity of hydrogels. To further obtain better nitrate adsorption capacity, Stansell tested freeze thawing to increase the surface area and porosity of the hydrogels. In the future, he would like his system to be tested in a functioning soil system and made more economically feasible.
“I learned that to try early and fail is better than to not try and not find out how something works,” he said. “Failure often happens in research projects, so it’s important to adjust to things not going as planned.”