Fighting for Water Sustainability
In Laudato si’, Pope Francis wrote that it is those suffering from poverty who will most experience the effects of climate change. Already, he says, they often bear the burden of water scarcity. He writes:
“Access to safe drinkable water is a basic and universal human right, since it is essential to human survival and, as such, is a condition for the exercise of other human rights. Our world has a grave social debt towards the poor who lack access to drinking water, because they are denied the right to a life consistent with their inalienable dignity. This debt can be paid partly by an increase in funding to provide clean water and sanitary services among the poor.”
Today, 1.1 billion people lack access to water, but by 2025 it is predicted that two-thirds of the global population will be impacted by water scarcity. Notre Dame researchers hope to change that.
Tengfei Luo, the Dorini Family Professor for Energy Studies in the College of Engineering, and Brandon Ashfeld, an organic chemist in the Department of Chemistry and Biochemistry, combined their unique specialties to address the issue of water scarcity. Luo has been developing a version of directional solvent extraction, a system to desalinate water, since graduate school. Ashfeld designs ionic liquids, which can effectively desalinate water.
Together, their new technology purifies water using 10 times less energy than traditional methods, and costs far less.
There are existing ways to convert salt water to fresh water that have been implemented globally to help mitigate the water shortage, but their outputs are detrimental. Luo explains that thermal desalination typically uses fossil fuels to heat the water, while reverse osmosis requires expensive membranes to push the water through, and still requires electricity. Both methods also leave a salty brine residue, which is typically dumped back into the ocean, causing further ecological issues.
The technology created by Luo and Ashfeld has almost no liquid discharge, and instead has a crystallized salt output that can be reused. The system is also ideal for remote or under-resourced communities as it is cost effective compared to traditional methods, and can use solar energy to heat the water to a mere 45 degrees Celsius. What’s more, this system can also remove other toxic salts, like arsenic, from contaminated water sources, further increasing access to safe water.
The duo is currently working to form a company as the first step in transitioning this technology to market and to those most in need.
