Hydrogel based water purification system 12 times better than current systems

**Hydrogel based water purification system 12 times better than current systems

A team of researchers from the University of Texas at Austin, collaborating with a group from the Lockheed Martin Corporation, has developed a new hydrogel-based water purification system—it is approximately 12 times better than existing commercial systems. In their paper published in the journal Science Advances, the group describes their system and how well it tested.

The world needs an inexpensive way to extract from . Every day, millions of people are forced to drink that is unfit for human consumption. In many cases, the places that need the water the most are not included in large purification efforts, thus, personal systems are needed. The most common way to purify water in small amounts is to make and use a solar-based water distillation system in which a bottle painted black on the bottom is exposed to the sun. As the water evaporates, it collects on the upper exposed surfaces of the bottle and trickles down into a container. While this method works quite well as a means of extracting , it is very inefficient as evaporation starts only when the bottle and its entire contents are heated. In this new effort, the researchers developed a vastly more efficient systems.

The new work by the team was based on work they did last year. In that effort, they created a sponge-like material made from two hydrogels—one was water-binding, the other light absorbing. When the sponge was placed atop the dirty water in a solar still, it forced the water inside to evaporate faster than normally. This was due to the layer of water that was touching the sponge forging weaker hydrogen bonds. That effort pushed the efficiency of the solar still to 3.2 L/h/m2 of water—which, the researchers claim, was more than twice the theoretical limit. In this new effort, the researchers improved that efficiency even more by adding chitosan (another polymer) to the mix. Doing so allowed the sponge to hold more water, leading to faster evaporation. This pushed the efficiency of the solar still to 3.6 L/h/m2, which, the researchers claim, is 12 times better than commercial units.

Fabrication process of the h-LAH. Credit: Xingyi Zhou and Fei Zhao, UT Austin
Outdoor demo of the h-LAH based solar water purification. Credit: Xingyi Zhou and Fei Zhao, UT Austin

Explore further

Solar-powered moisture harvester collects and cleans water from air

More information: Xingyi Zhou et al. Architecting highly hydratable polymer networks to tune the water state for solar water purification, Science Advances (2019). DOI: 10.1126/sciadv.aaw5484
Journal information: Science Advances

© 2019 Science X Network

Citation: Hydrogel based water purification system 12 times better than current systems (2019, July 1) retrieved 22 July 2019 from https://phys.org/news/2019-07-hydrogel-based-purification-current.html
This document is subject to copyright. Apart from any fair dealing for the purpose of private study or research, no part may be reproduced without the written permission. The content is provided for information purposes only.
1 shares

Feedback to editors

User comments

Please sign in to add a comment. Registration is free, and takes less than a minute. Read more