Citizen Science Project Develops Nanotube Filtration Systems For Clean Water

Researchers at Tsinghua University and Tel Aviv University developed a framework for a new nanotechnology-based strategy to improve water filtration.

The project, called Computing for Clean Water, was led by Prof. Quanshui Zheng of the Tsinghua Center for Nano and Micro Mechanics and Prof. Michael Urbakh of the Tel Aviv University School of Chemistry, in collaboration with Prof. Francois Grey of the University of Geneva.

More Efficient and Less Expensive Water Filters

ibm-nanotubesThe results of the project, published in Nature Nanotechnology with the title “Water transport inside carbon nanotubes mediated by phonon-induced oscillating friction,” show that carbon nanotubes can be used to make water filters that are more efficient and less expensive. Carbon nanotubes are made of single-atom-thick sheets of carbon atoms rolled up into tiny tubes, with diameters of just a few nanometers – one ten-thousandth the diameter of a human hair. The size of the tubes allows water molecules to pass through, but blocks larger pathogens and contaminants, purifying the water.

The scientists demonstrated that, under suitable conditions, water can pass through nanotubes much more easily than previously predicted. The research result could permit developing techniques to improve access to clean water through more efficient water filtration and desalination, which is very important because billions of people in the developing world don’t have access to clean water for drinking and hygiene. There are possible applications in clean energy and medicine as well.

The researchers carried out extensive computer simulation of the flow of water through nanotubes to demonstrate that water transport can be enhanced, and sanitation and desalination improved, by appropriately exploiting phonon oscillations – vibrations of water-carrying nanotubes. Under the right conditions, such vibrations produce a 300 percent improvement in the rate of water diffusion.

Prof. Urbakh said:

With these oscillations, we witnessed three times the efficiency of water transport, and, of course, a great deal of energy saved.

Citizen Scientists Play an Important role in Scientific Breakthroughs

Since the required simulations are very computing intensive, the researchers enlisted the help of over 150,000 volunteer citizen scientists, who contributed their own computing power to the research via the World Community Grid, an IBM initiative that enables participants to donate their unused computing power to advance cutting-edge scientific research on topics related to health, poverty and sustainability.

“We could never have managed with just four students in the lab,” said Prof. Urbakh. “We would have required the equivalent of nearly 40,000 years of processing power on a single computer. Instead we had the benefit of some 150,000 computing volunteers from all around the world, who downloaded and ran the project on their laptops and desktop computers.”

Prof. Grey, who also manages the Citizen Cyberscience Centre established by CERN, the UN Institute for Training and Research and the University of Geneva, commented on the broader significance of this result:

Computing for Clean Water and similar volunteer computing initiatives are playing an increasingly important role in major scientific computing breakthroughs, ranging from drug discovery and climate modeling to epidemiology and particle physics research.

He added that the range of research questions that can benefit from public participation is growing all the time, in step with the power of personal computing.

Images from IBM and Shutterstock.

Giulio Prisco is a freelance writer specialized in science, technology, business and future studies.