While attending the EuroNanoForum 2011 conference this week in Budapest, Hungary, I was confronted with at least once considering how nanotechnology could be used in water purification and desalination. You really can’t get through one of these things without hearing how nanotechnology could save the world.
But the water issue is one that over the years I have taken some interest in, putting together a conference on the subject seven years ago, and even taking up the issue here on Spectrum’s pages here, here and here. A couple of years back, the Meridian Institute published a good white paper entitled “Conventional and Nano-Based Water Technologies,” which did a nice job of cataloguing all the nanotech-based solutions for water desalination. We have another one to add to that list possibly in a recent article published Physics World written by Jason Reese, Weir Professor of Thermodynamics and Fluid Mechanics at the University of Strathclyde.
The article relates how CNTs are enabling a technique used by Reese that moves away from the high-energy-cost process of reverse osmosis. In this technique, Reese has shown that the CNTs can improve water permeability 20 times that of modern commercial reverse-osmosis membranes. A factor of 20 improvement in permeability should have a pretty significant impact on the energy requirements.
This is certainly a move in the right direction. However, I have to confess that when I put the NanoWater conference together seven years ago, I had somewhat greater expectations that we would be further along at this point. I am not entirely convinced it’s a lack of technological solutions, nanotech related or otherwise, that is the cause of the delay.
Dexter Johnson is a contributing editor at IEEE Spectrum, with a focus on nanotechnology.