Fruit and Vegetable Peels as Efficient Renewable Adsorbents for Removal of Pollutants from Water: A Research Experience for General Chemistry Students

Sustainability is emerging as a prominent curricular initiative at the undergraduate level, and as a result, involving students in real-world problems in the classroom and laboratory is an important goal. The specific problem of a dwindling supply of clean and safe drinking water is also of utmost importance and relevance. This general chemistry laboratory curriculum provides first-year students with an opportunity to design and implement their own experiments that employ fruit and vegetable peels as adsorbents to remove pollutants from water. The project is nine laboratory periods long, with the first 2 weeks devoted to providing students with the necessary tools to perform original research. In the third week, students visit the Dickinson College farm and brainstorm possible hypotheses. Working in pairs, students perform original research in the fourth through sixth weeks and investigate adsorption capacity and percent removal. In the final 3 weeks, students perform calculations and engage in peer review of their posters, which are presented at an all-college public poster session. This project introduces students to UV--vis and AA spectroscopy, making standard solutions and employing Beer's Law, as well as literature searching and experiment design. If time allows, FTIR spectroscopy may be employed to examine the chemical makeup of the peels. This curriculum can be used in subsets with additional guidance in a standard two-semester introductory course sequence.