By Sara Jerome,
Next time you eat an orange or a grapefruit, save the peel. It may be useful for wastewater purification.
Claiming that the method may eventually compete with activated carbon as a treatment technique, researchers published a study in the Journal of Chemical Technology and Biotechnology testing their peel hypotheses. They built on previous research published in Industrial Crops and Products.
The researchers used a technique known as “controlled pressure drop treatment” to modify the structure of the peels. The treatment made them more porous and increased their surface area.
The researchers then treated the peels chemically, adding functional groups to the materials, making them capable of removing pollutants from wastewater.
The latest study showed that “it is possible to pack those new materials in fixed bed columns, in a way similar to standard wastewater treatments. This laboratory-scale study has obtained parameters to design a large-scale use of the materials,” according to a statement from the University of Granada.
Romero Cano, one of the researchers, explained the significance of the findings.
"The results show a great potential for the use of said materials as adsorbents capable of competing with commercial activated carbon for the adsorption and recovery of metals present in wastewater, in a way that could make it possible to carry out sustainable processes in which products with a great commercial value could be obtained from food industry residues," he said.
Previous research has demonstrated that an array of fruit and vegetable peels, including apple, banana, and tomato peels, can also be useful for water purification.
Researcher Ramakrishna Mallampati, for instance, “studied the structure of the tomato peels to assess their efficiency as biomaterials to remove toxic metal ions and organic pollutants from water,” according to a statement from the National University of Singapore.
The study revealed that tomato peels can remove water contamination, including dissolved organic and inorganic chemicals, dyes and chemicals, and can be used in large-scale treatment operations.
For similar stories visit Water Online’s Wastewater Contaminant Removal Solutions Center.