Researchers at Massachusetts Institute of Technology (MIT) have developed an ultrasonic device that transforms how captured water is extracted from atmospheric-water-harvesting sorbents. Traditional systems rely on solar heating to evaporate water from a sponge-like material, a process that often takes hours or even days, tells MIT News.
The MIT team’s device uses high-frequency vibrations, such as ultrasound, to “shake” water molecules loose from the sorbent material. When a sample of the sponge material is placed on a vibrating ceramic ring, droplets form and fall through tiny nozzles into a collection vessel. Tests showed that the ultrasonic method dried the sorbent in minutes rather than the long cycles needed with thermal systems.
In their experiments, the ultrasonic actuator proved approximately 45 times more efficient than the solar-evaporation approach when extracting water from the same material sample. The system is designed to complement existing sorbents rather than replace them, meaning it could be integrated into current harvesting setups. A future version could run on a small solar cell, turning on automatically when a sorbent is saturated, allowing repeated water-harvest cycles within a single day.
The researchers see promise for this technology in arid and remote regions where conventional water sources are scarce, particularly where even seawater desalination is impractical. By dramatically reducing extraction time and improving cycle frequency, this ultrasonic approach adds a significant new tool to the field of atmospheric-water harvesting, potentially turning humidity in even dry air into a practical, repeatable water resource.