Shanghai scientists develop gel to harvest water in arid zones

Shanghai scientists have developed technology capable of procuring drinkable water from extremely arid environments, courtesy of a special gel.

These Shanghai researchers have utilized a highly hygroscopic gel to create a device powered by solar energy, which could potentially supply drinking water to inhabitants of some of the driest regions on Earth. A kilogram of the dry gel can adsorb 2.6 pounds of water in a dry atmospheric environment, and up to 14.1 pounds in a high-humidity setting.

A detailed description of this groundbreaking device was published in the journal "Applied Physics Reviews" (doi: 10.1063/5.0160682). Researchers at Shanghai Jiao Tong University in China harnessed the power of a super hygroscopic gel in their device, which is capable of absorbing and retaining a significant quantity of water.

The groundbreaking technology developed by these Chinese researchers holds promise for aiding populations in regions globally challenged by limited water access. According to a United Nations report on global water management published in March 2023, more than 2.2 billion people reside in countries grappling with water scarcity.

Furthermore, approximately 3.5 million individuals die annually as a result of illnesses associated with contaminated water or water scarcity. UN experts project that clean drinking water availability may plunge by 40% in the coming decade, and by 2050, half of global civilization may be impacted by water deficit.

Water shortage predominantly impacts residents of tropical and subtropical areas, as well as those situated within continents. These areas facing severe water deficiency also happen to be some of the sunniest regions in the world, thus a solar-powered device like the one developed by the Chinese scientists could be particularly beneficial.

The device pioneered in Shanghai doesn't just absorb humidity, but also disseminates it. Using a turbofan, it becomes possible to retrieve more than 90% of the water from the gel.

"This promising technology for gathering atmospheric water has the potential to augment potable, industrial, and personal hygiene water supply. The hygroscopic gel formulated by our team from plant-based compounds and salt is easy to manufacture and cost-effective, hence suitable for mass production," explains Ruzhu Wang from the Refrigeration and Cryogenics Institute at the University of Shanghai.