We all know fruit and vegetable peels have a lot of nutrition in them, but who knew they could be used as water filters?
Tomato and Apple Peels
Tap water and bottled water are filled with a variety of chemicals. Completely pure, drinking water is almost impossible to come by. This is why Mr. Ramakrishna Mallampati, a PhD candidate at the National University of Singapore has been researching different natural ways to filter water. He plans to use this design to help rural areas in developing countries with their water problems..
They discovered that apple and tomato peel, two of the most commonly consumed ingredients, are exceptionally useful in absorbing harmful substances. The peel of the tomato or apple was soaked in an alcohol solution. After that, you take the peels out and leave them to dry, and when they are fully dehydrated they are put in a vessel with water. After a few hours, the peels are removed from the water, and the water is safe for drinking.
The research showed that tomato peel can efficiently remove harmful substances from the water including dissolved organic and non organic chemicals, dyes and pesticides. Similarly, the apple peel can remove various dissolved pollutants from the water through the process of adsorption. In order to improve the ability o of the apple peel in removing pollutants, Ramakrishna applied a natural zirconium oxide onto the peel’s surface.
It was established that a peel can pull out anions such as phosphate, arsenate, arsenite and chromate ions from aqueous solutions. The researchers are already testing the effects of other fruits’ peels, especially fruits used in the communities which are in need of clean water. Ramakrishna stated that he does not want any commercial use from this method – he has been working with non governmental institutions so the information can remained untouched by corporate entities.
A recently conducted study established that the compounds in the banana contain nitrogen atoms, sulfur and organic compounds such as carboxylic acid.
These acids have free, negatively charged electron pairs, meaning they can attach to metals in the water which are usually positively charged.
Coconut fiber and rice husk
In 1972 in Thailand, a group of scientists worked to develop a new way of filtration which proved to have a wide application for cleaning polluted waters in Southeast Asia. This technology is consisted out of two phases.
The first phase is consisted of fibers from shredded coconut husk with which most of the suspended harmful substances in the water are filtrated and the other phase is burned rice husks which are able to remove residual turbidity and other contaminants.
Alongside with being used as a filtration process, the burned rice husks have a significant absorption capability for removal of taste, odor and color.
Solar disinfection with the help of lime
Solar disinfection of water, combined with almost every type of citrus is very efficient in lowering the danger from E. coli; among which lime proved to be the most efficient one. A recent study published by the Johns Hopkins School of Medicine discovered that adding lime in water that is being disinfected on the sun speeds up the process.
The preliminary results from the research showed that solar disinfection of water combined with citrus fruits can be efficient in lowering the level of E. coli in only 30 minutes which is the equally needed time for boiling water and other methods for cleaning water in the household. Although these methods may not be all- encompassing water filters since they do not remove all pathogens, they efficiently remove heavy metals and other contaminants in a cheap, simple and ecologically acceptable way.
Original Article : thespiritscience
By: Violeta Pesic
National University of Singapore.