Materials

Sponge-like aerogel turns airborne vapor into drinkable water

Sponge-like aerogel turns airb...
A newly developed aerogel is able to turn molecules in the air into liquid water
A newly developed aerogel is able to turn molecules in the air into liquid water
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A newly developed aerogel is able to turn molecules in the air into liquid water
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A newly developed aerogel is able to turn molecules in the air into liquid water
The research team behind a new aerogel that collects water from the air, Professor Ho Ghim Wei (left), Dr Gamze Yilmaz (center) and Dr Fan Lu Meng (right)
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The research team behind a new aerogel that collects water from the air, Professor Ho Ghim Wei (left), Dr Gamze Yilmaz (center) and Dr Fan Lu Meng (right)

Water security is a significant problem and pulling it out of the air, as fanciful as that may sound, is shaping as a potential part of the solution. A team from the National University of Singapore (NUS) has put forward a promising example of this type of technology, demonstrating a spongey aerogel that turns airborne water molecules into drinkable liquid, without needing a power source or having any moving parts.

The notion of wringing water out of the atmosphere is an area of scientific research where we are seeing quite a lot of activity. These types of technologies may be sophisticated devices that act as solar-powered greenhouses that release trapped water vapor, or be as rudimentary as nets in the desert that collect moisture from the fog that sweeps through from the sea.

The material created by the NUS engineers also appears a relatively simple solution. The aerogel is made up of long snake-like polymers combined with what’s known as a metal-organic framework, porous structures that are highly valued in many fields of research for their incredibly high surface area.

The team's hybrid material offers just the right chemical structure to continuously and simultaneously attract and repel water. In practice, this means that the aerogel can autonomously collect water molecules from the air, condense them into a liquid and then release it, much like a sponge, although it doesn't need to be squeezed to release its collected cargo. Its performance is enhanced when exposed to sunlight, which promotes its water-repelling abilities and enables it to turn 95 percent of the vapor it absorbs into liquid water.

The research team behind a new aerogel that collects water from the air, Professor Ho Ghim Wei (left), Dr Gamze Yilmaz (center) and Dr Fan Lu Meng (right)
The research team behind a new aerogel that collects water from the air, Professor Ho Ghim Wei (left), Dr Gamze Yilmaz (center) and Dr Fan Lu Meng (right)

In laboratory testing, the team was able to demonstrate continuous operation of the material for 1,440 hours, with the water it produced meeting the World Health Organization’s standards for drinkable water. In humid conditions, the researchers report that 1 kg (2.2 lb) of the material can produce 17 liters (4.5 gal) of water per day, though the aerogel is said to weigh almost nothing, so you may need a lot of space to house a collector of that size.

The researchers point to the simplicity of the design, in that it needs no sunlight or electricity to function and involves no moving parts, as its advantages over other water harvesting devices, and they are now looking for commercial partners to ramp up development of the technology.

“Given that atmospheric water is continuously replenished by the global hydrological cycle, our invention offers a promising solution for achieving sustainable freshwater production in a variety of climatic conditions, at minimal energy cost,” says Professor Ho Ghim Wei, who led the research team.

The research was published in the journal Science Advances.

Source: National University of Singapore

8 comments
8 comments
McDesign
Here in the humid US south, air conditioning is as much about removing water as cooling the air. this may be a viable alternative.
Username
Out of the lab It would rapidly get dirty with dust and pollutants and possibly mold.
JustSaying
Can this work on Mars?
MC-NRG
There are also many basements in cooler areas that are prone to excess humidity as warm air infiltrating the basement condenses on cold floors and walls. Dehumidifiers are used to alleviate this and use a lot of electricity (they're heat pumps, just like fridges and AC's). An appliance with these sponges and a small fan (with filter) with the output water going into a drain (where does your washer hose outlet to?) might do it. Could be a big savings in $ and CO2.
Signguy
And whats the Aerogel cost...?
Wombat56
17 liters of water (that's also 17 kg) per kilo of MOF is a HUGE increase in efficiency compared to previous efforts. As the article says, the stuff weighs almost nothing so I wonder how much volume that would be? Maybe you could stack layers of it in trays with a fan blowing air through the stack and a filter at the intake end. At least you'd have enough water available to be able to wash the filter occasionally.
guzmanchinky
That is so cool. I'm always amazed by the breakthroughs scientists are pursuing every day.
TheMartian
I notice nothing is said about the reduction in relative humidity it can achieve. Nor about the minimum RH for it to work at all. Are those data available?