Research investigates the stability of nanobubbles and their impact on the real world

Gases are essential to many chemical reactions, and bubbles are one way to keep these gases in solution. Compared to larger bubbles, nanobubbles have improved stability. This means that nanobubbles can remain in solution for a long time without bursting. The increased stability increases the availability of gas in the solution and increases the time for chemical reactions to occur.

Texas A&M University researchers led by Dr. Hamidreza Samuei are investigating why nanobubbles (bubbles with a diameter smaller than a hair) are stable and what factors contribute to their stability. We are progressing in understanding. Their findings are published in the latest issue of The Journal of Physical Chemistry.

“When you inject gas on an industrial scale, you don’t want to waste that gas. You want to make the most of it for chemical reactions,” said Samuei, the Harold Vance assistant professor in the Department of Petroleum Engineering. “That’s the main purpose, to keep the gas in solution for a very long time, ideally infinite time, and to keep the gas in solution without bursting.”

The researchers found that the stability of the nanobubbles is mainly based on the nanobubbles’ charge and the interaction between the bubble’s charge and the solvent. The stability of nanobubbles is also influenced by additives in the solution.

Nanobubbles’ ability to hold gases in solution gives them many real-world applications such as wastewater treatment, hydroponics, and disinfection. When nanobubbles are used in hydroponics, plants grow larger than without nanobubbles. Nanobubbles make more oxygen available in the water, creating a better environment for crops to grow.

Understanding the stability of nanobubbles is a small piece of a larger research puzzle. Researchers have been injecting carbon dioxide into salt water solutions to extract various minerals from the solutions. Minerals collected using this method, known as brine mining, are used in a variety of applications, including lithium batteries and magnesium fertilizers.

“For this project, we needed a way to increase carbon dioxide concentration, so we used nanobubbles,” Samuei said. “Now that we have a better understanding of how to extend the lifetime of nanobubbles, they will become an important tool in saltwater mining practices.”

Dr. Mohammadjavad Karimi and Dr. Gholamabbas Parsafar also collaborated on this research.