The authors of the study wanted to uncover the potential of fruit and vegetable peels as part of a low-cost but efficient water purification process. They found that peels and seeds from okra, pumpkin, banana, and lemon, among others, could remove methylene blue, copper, and lead from water. Methylene blue is a dye, while lead and copper are heavy metals – and all are known to be common water pollutants.
The peels and seeds removed these substances through adsorption, a process in which solids attract molecules or atoms from liquids and gases to their surface. The attracted molecules coat the surface of the solid object, usually as a filmy layer. A good example of adsorption in action is how the charcoal filters in gas masks capture poisonous molecules to clean and detoxify passing air.
The study on vegetable and fruit peels is a follow-up to an earlier research project that confirmed the ability of peels from avocado, Hami melon, and dragon fruit to remove methylene blue from water. The recent inquiry employs some of the methods used in its predecessor, particularly in preparing the peels.
The fruit and vegetable peels and seeds are first boiled to remove any soluble impurities on their surface. They are then dried and crushed before they are placed in a solution that is contaminated with pollutants. Among the study's findings was that okra peels and lemon seeds are excellent at adsorbing lead ions. Both of these materials were able to adsorb 100 percent of lead ions, while lemon peel and okra seeds were able to adsorb 96.4 and 50 percent of lead ions, respectively.
Cindy Samet, a professor at Dickinson College and one of the authors of the study, believes that the findings may pave the way for affordable technologies that countries with a low supply of clean, potable water can tap.
“This is exciting because it is likely that this method of purification can make its way from lab to kitchen,” she said.
Hydration is essential to life, but drinking contaminated drinking water can be very dangerous to human health. Here are some of the most common water-borne contaminants in drinking water:
Learn about the dangers of toxins in water at CleanWater.news.