A new graphene water filtration and recycling system has been developed which uses graphene oxide with a cheaper material to create a recyclable membrane.
“Concern that the U.S. military could run out of water while washing tanks and trucks exposed to chemical and biological weapons has led to inventions with non-military applications.
A new water recycling system built by the U.S. Army Engineer Research and Development Center’s Environmental Laboratory solves the problem by filtering out the bad stuff, which allows the wastewater to be reused or dumped.
Known as the Decontamination Effluent Treatment System, it can filter up to 600 gallons of wash water per hour, according to Victor Medina, a research engineer in the Army lab.
But an offshoot of Medina’s work has led to a new filter membrane made of graphene oxide, a unique material with a tendency to self-assemble in layers, creating narrow channels that are perfect for filtering water.
“He came in and said, ‘We need to create a piece of membrane material as big as my desk,’” said Chris Griggs, a research chemist and one of Medina’s colleagues. “And Jose Mattei-Sosa–a chemical engineer on my team–and I looked at each other and said, ‘OK’.”
While graphene oxide is great as a filter, it’s also really expensive, around $250 per gram expensive, so the researchers wanted a way to recycle it to lower production and lifecycle costs.
Using chitosan, which is made of crustacean shells and is relatively inexpensive, the researchers were able to bind the graphene oxide into a recyclable membrane.
“As far as we know, our team has the largest graphene oxide membranes in the world,” Griggs said.”
Source: Tech Link Center
Image: Jose Mattei-Sosa and Drs. Victor Medina and Chris Griggs receive U.S. Patent 10,414,659 for their method of recycling chitosan and graphene oxide compound for water purification purposes. Credit: Chris Rosario/Army Corps of Engineers