Dr. Dinh Van Phuc and his colleagues treated pomelo peel to absorb lead, nickel, and cadmium in wastewater, with more success than other materials.
Dr. Dinh Van Phuc, from the DTU Institute of Fundamental Science & Applications, lives in Dong Nai, famous for the Tan Trieu pomelo, grown in the Vinh Cuu district. He noticed that the people there only process the flesh of the pomelos, but leave the peel as waste. In his research into environmentally-friendly materials, Dr. Dinh Van Phuc experimented with the peel, which contains mostly cellulose, pectin and other organic compounds, to attempt to create an adsorbent for special heavy metals. Cellulose and pectin contain the - OH and - COOH functional groups, which interact electrostatically with metals and form complexes. The Pomelo peel is also spongy, allowing heavy metal ions to be retained internally.
Dr. Dinh Van Phuc in his office. Photo: NVCC
His research team first extracted essential oils and other organics from the peel, which can cause damage in contact with water, and then dried it. The processed pomelo peel was then submerged in water polluted with heavy metals for about two hours, and the toxins were then filtered out of the water. To determine the heavy metal adsorption capacity of the pomelo peel, Dr. Phuc investigated the influence of pH, time, concentrations and its interaction with the heavy metals and other substances.
Compared to several other peels that were considered, such as chaff and banana peel, pomelo absorbs lead, cadmium and nickel better, at 47,18 mg/g, 13,35 mg/g, and 9,67 mg/g respectively, with lead the best due to its superior interaction with the pomelo peel components.
Water polluted with heavy metals is found mostly in industrial zones and in dense urban areas. It pollutes drinking water pollution and affects public health. Metals are colorless and odorless and difficult to detect, and installing and maintaining filters is costly.
Dr. Dinh Van Phuc and his colleagues plan to use agricultural by-products to conveniently solve the problem of water pollution at a reasonable price. He stated that his group has now decided to combine the pomelo peel with other waste products, like pineapple leaves and banana peel for better absorption and easier processing.
(Media Center)