Ultrasound: A Faster Route to Water Recovery

Researchers have developed an ultrasonic device capable of generating high-frequency vibrations to speed up water extraction. When a water-absorbing material, known as a “sorbent,” is placed on the device, carefully tuned ultrasound waves shake loose the trapped water molecules. Tests show that this method can release moisture within minutes—much faster than traditional heat-based systems, which often require tens of minutes or even hours.

Figure 1. MIT’s Ultrasonic Device Pulls Drinkable Water from Air.

Since the device operates without heat, it relies on an external power source. The team proposes using a small solar cell that could not only power the system but also detect when the sorbent has reached its maximum water capacity. This setup could be automated so the device activates only when enough water is ready to be collected, enabling a fully self-running water-harvesting system. Figure 1 shows MIT’s Ultrasonic Device Pulls Drinkable Water from Air.

“People have long searched for efficient ways to pull water from the atmosphere, a resource especially valuable in deserts and regions without access to seawater for desalination,” explains Svetlana Boriskina, principal research scientist in MIT’s Department of Mechanical Engineering. “This approach finally provides a fast and efficient solution.”

The Stubborn Challenge of Extracting Moisture

A new direction emerged when Ikra Shuvo joined the group. Shuvo had been developing ultrasound-based technologies for wearable medical devices. While discussing new research possibilities, he and Boriskina realized that ultrasound might offer a faster way to release water from AWH materials.

“It just clicked,” recalls. “We had this major challenge, and Ikra had a tool that could directly help address it.” Boriskina

How Ultrasonic Waves Shake Water Free

Ultrasound consists of acoustic pressure waves that vibrate at frequencies above 20 kilohertz—too high for the human ear to detect. The MIT team discovered that this frequency range is ideal for loosening water molecules from the surfaces where they are bound.

“With ultrasound, we can precisely break the weak bonds between water molecules and the spots where they adhere,” Shuvo explains. “It’s as if the water starts ‘dancing’ with the waves. This targeted disturbance creates enough momentum for the molecules to break free, which we can actually see as droplets shaking loose.”

To exploit this effect, Shuvo and Boriskina designed a new ultrasonic actuator tailored for water release in AWH systems. At its core is a flat, vibrating ceramic ring activated by an applied voltage. An outer ring equipped with small nozzles surrounds it, allowing the released droplets to fall through into collection containers positioned above and below.

Designing a High-Frequency Water-Release Device

The team tested the actuator using an AWH material they had previously developed. They placed small, quarter-sized samples in a humidity chamber at various moisture levels until each piece became fully saturated. After transferring the samples to the ultrasonic actuator and activating it, they found that in every case the material dried out within mere minutes.

Testing the Actuator in Realistic Conditions

Their calculations show that the ultrasonic method is 45 times more energy-efficient than using solar heat to release water from the same sorbent material.

“The beauty of this device is that it can complement almost any sorbent,” Boriskina explains. She envisions a practical home-scale system made of a fast-absorbing material paired with an ultrasonic actuator, each roughly window-sized. Once the sorbent becomes saturated, the actuator—powered by a small solar cell—could briefly activate to shake out the water. The material would then be ready to absorb more moisture, enabling multiple collection cycles throughout the day.

Source: SciTECHDaily

Cite this article:

Priyadharshini S(2025), MIT Unveils Ultrasonic System That Condenses Potable Water from Ambient Air, AnaTechMaz, pp.424