Portable fresh water harvester can pull 10 gallons per hour from air

A new type of water harvester that could take advantage of the abundant water particles in the atmosphere.

A new portable freshwater harvester would likely even work in desert environments that have little moisture
A new portable freshwater harvester would likely even work in desert environments that have little moisture. Image: Shutterstock

Scientists at the American Chemical Society, by drawing inspiration from ancient in the Middle East and South America, are developing a light-weight, battery-powered freshwater harvester. This harvester, scientists noted, could potentially pull 10 gallons of water per hour from the air.

Shing-Chung (Josh) Wong, Ph.D., said, “I was visiting China, which has a freshwater scarcity problem. There’s investment in wastewater treatment, but I thought that effort alone was inadequate. Instead of relying on treated wastewater, we thought it might be more prudent to develop a new type of water harvester that could take advantage of the abundant water particles in the atmosphere.”

Wong along with his students turned to electrospun polymers, a material they had already worked with for more than a decade. Electrospinning utilizes electrical powers to deliver polymer fibers running from many nanometers up to 1 micrometer — a perfect size to consolidate and crush water beads out of the air.

These nanoscale fiber polymers offer an unfathomably high surface-zone to-volume ratio, significantly bigger than that given by the typical structures and membranes utilized in water distillers.

By trying different things with various combinations of polymers that were hydrophilic — which pulls in water and hydrophobic which releases water, the group presumed that a water collecting system could indeed be created utilizing nanofiber innovation. Wong’s group verified that their polymer film could harvest 744 mg/cm2/h, which is 91 percent higher than comparable designed membranes without these nanofibers.

Due to the high surface-area-to-volume ratio, the harvester could work in arid desert environments. In addition, this harvester grabs water and filters it. The electrospun fiber network can act as an anti-fouling surface, sloughing off microbes that could collect on the harvester’s surface.

Wong said, “We could confidently say that, with recent advances in lithium-ion batteries, we could eventually develop a smaller, backpack-sized device.”

Next, Wong hopes to obtain additional funding to build a prototype of the freshwater harvester. He anticipates that, once his team is able to produce the prototype, it should be inexpensive to manufacture.

Wong acknowledges funding from the University of Akron. The researchers will present their results today at the 256th National Meeting & Exposition of the American Chemical Society (ACS). ACS, the world’s largest scientific society.