Liquid Metal Tin Powers Sustainable Water Desalination

Liquid Metal Tin Powers Sustainable Water Desalination
by Riko Seibo
Tokyo, Japan (SPX) May 13, 2025

Water scarcity remains a critical global issue, impacting over two billion people worldwide. As climate change and population growth exacerbate this crisis, researchers are increasingly focused on seawater desalination as a vital solution to meet growing freshwater demand. However, conventional desalination processes generate approximately 141.5 million cubic meters of brine waste daily, presenting significant environmental challenges due to its high concentration of metallic elements and the energy-intensive nature of existing recovery methods.

A team led by Associate Professor Masatoshi Kondo from the Institute of Science Tokyo (Science Tokyo) has developed a breakthrough desalination technology using liquid metal tin, offering a sustainable approach to purify water and recover valuable metals. Their study, published in the journal Water Reuse on March 1, 2025, outlines a method where brine is sprayed onto a liquid tin surface heated to 300 C. This process instantly evaporates pure water while valuable metals, including sodium, magnesium, calcium, and potassium, remain in the molten tin.

"The main energy source for this type of seawater desalination can be concentrated solar power, as heat is the primary requirement, reducing dependence on electricity and enabling a more sustainable process," Dr. Kondo explains. The approach also minimizes secondary waste and carbon emissions, making it an environmentally friendly alternative to conventional desalination technologies.

After the initial separation, the molten tin undergoes a controlled cooling process, allowing specific metals to precipitate at distinct temperatures for targeted recovery. Laboratory tests showed that potassium precipitates first, followed by sodium, calcium, and finally magnesium, offering precise metal extraction.

The technology's versatility extends beyond seawater treatment, with potential applications in removing toxic metals from polluted groundwater. "The proposed technology can also distill groundwater contaminated with arsenic without consuming large amounts of energy or generating hazardous waste," notes Dr. Kondo, highlighting its potential to address widespread contamination issues in regions like Bangladesh, India, and Vietnam.

By transforming desalination brine from a waste product into a valuable resource, this innovative liquid metal approach offers a promising path toward sustainable water management and resource recovery, potentially reshaping global water treatment practices.

Research Report:Liquid metal technology for collection of metal resources from seawater desalination brine and polluted groundwater