US’ new method extracts 14 liters drinking water from thin air daily using food scraps.

Researchers at the University of Texas at Austin have developed a new method to extract clean drinking water from the air using everyday biomass such as food scraps and seashells. This system transforms biomass into "molecularly functionalized biomass hydrogels" that harvest water directly from the atmosphere.

The research team has developed a two-step process to modify natural polysaccharides at the molecular level, enhancing their ability to capture moisture from the air and release it easily when heated. This process involves attaching thermoresponsive and zwitterionic groups to the materials.

Field tests have demonstrated that a single kilogram of the hydrogel material can yield up to 14.19 liters (3.75 gallons) of water per day, significantly surpassing existing atmospheric water harvesting technologies. The researchers have successfully demonstrated its effectiveness with cellulose, starch, and chitosan.

Unlike many existing water harvesting technologies, this new method can extract meaningful quantities of water even in arid environments. The biomass-based hydrogels are biodegradable and can be produced from readily available materials that would otherwise be discarded.

The research team is now working on scaling production and designing real-world device systems for commercialization, including portable water harvesters, self-sustaining irrigation systems, and emergency drinking water devices.