MIT researchers have tested a water filter fashioned from a tree branch that may be the low-cost solution to water filtration in developing countries.
New research from MIT has revealed that nature may have an inexpensive solution for water filtration. By taking a small piece of a simple pine tree branch, peeling off the bark, and fastening it to the end of a tube through which water will be poured, you can create a filter good enough to remove 99.9% of E. coli from water.
At least, those were the results reported by MIT mechanical engineers in a paper published yesterday in PLOS One. "I listened to this talk about how water flows through plants, and it occurred to me that the flow of water has to pass through these membranes in xylem," said Rohit Karnik, coauthor of the study. Xylem is part of a plant's vascular system, which transports water and dissolved minerals throughout its body. "We tried freshly cut sapwood and found that it actually works," Karnik says. "We were able to show that it can filter."
According to Rick Andrew, global business development director of water systems at the National Sanitation Foundation International, these sapwood filters could potentially be the low-tech solution for water purification. He does have his reservations, however - tests will need to be conducted to determine how the filter holds up to heavily polluted water, which may clog it.