Last year I tried to establish a blog tradition of starting the new year with a hopeful science news item, something that shows enormous technological potential to change the world for the better. But come New Years, it didn’t work out, the Quantum Computing and D-Wave news was simply moving too fast, and I also didn’t come across anything that felt significant enough.
Not any more. Recently a breakthrough discovery has been made that has the potential to rival the impact of the ammonium synthesis. When Fritz Haber discovered this process in the early 20th century, he single-handily vanquished famines from the developed world as subsequently fertilizer became an inexpensive commodity. This new discovery has the potential to do the same for thirst and droughts. It involves a surprising property of graphene and does justice to the hype that this miracle-material receives: Although graphene is usually hydrophobic it can be made to form capillaries that efficiently absorb water. Now researchers at the University of Manchester report having formed layers of graphene oxide that exploit this property to make efficient water filters on the molecular level.
These filters are reported to work astoundingly efficiently, keeping anything out above the size of nine Angstrom (9.0 × 10-10 m) at a speed comparable to an ordinary coffee filter. It is essentially sieving on the molecular level. This is not yet enough to remove ordinary sea salt, but the scientists, who just published their research in last week’s issue of Science, are confident that the material can be scaled down to this level.
If so, it will change the world. Desalination of sea water is currently only affordable to the wealthiest countries, as the required investments are staggering, and operating the necessary infrastructure is very energy intensive. For instance, Saudi Arabia recently commissioned the world’s largest desalination plant for US$ 1.46 billion. The scope of the project is impressive, yet this amount of money will still only suffice to supply one large city metropolis with enough water (~3.5M people).
According to a new report by the Worldwatch Institute, 1.2 billion people, or nearly a fifth of the world’s population, live in areas of physical water scarcity, i.e. places where there is simply not enough water to meet demand. Another 1.6 billion face economic water scarcity, where people do not have the financial means to access existing water sources. If this research succeeds in creating a material that can simply filter out sea salt, and if its production can be scaled up, then this scourge on humankind could be rapidly diminished.