Rutgers University held its commencement ceremony on May 17. The guest speaker was Bill Nye, best known for his Emmy-winning children’s TV series “Bill Nye the Science Guy” in the 1990s. Nye studied mechanical engineering at Cornell University and began his professional career at The Boeing Company, where he developed a hydraulic pressure resonance suppressor that is still used in the Boeing 747. In recent years he has developed sundials for the Mars Exploration Rover missions, served on the board of the space-interest The Planetary Society, and debated creationist Ken Ham about evolution.
In his commencement speech at Rutgers, Nye touched on scientific topics such as space exploration, climate change, and the use of graphene to provide clean drinking water: “It has been recently shown that we may be able to use carbon in another way to produce fresh water from seawater with a fraction of the energy required, right now, using sheets of carbon a single atom thick-graphene,” he said. “The seawater’s fluid slip-length is longer than a carbon atom is wide. Water can slide on through and leave the salt behind. It’s wild. If this idea proves workable, you all could use it to provide clean water to everyone on Earth.”
Scientists at Oak Ridge National Laboratory recently demonstrated this theory by using free-standing, porous graphene to desalinate saltwater. Currently, water is purified using methods such as distillation (requiring a significant amount of energy) and reverse osmosis (which is more energy-efficient but still requires a fair amount of energy).
The reverse osmosis technique is the basis for the ORNL technology. Water molecules are not small enough to pass through graphene’s fine mesh. However, the water molecules can penetrate if larger holes — but still not large enough for salt ions to pass through — are poked in the graphene. The reseachers determined the necessary size of these holes by using aberration-corrected scanning transmission electron microscopy imaging, which allowed for atom-resolution imaging of the graphene. They have determined that the optimum pore size for effective desalination is 0.5 to 1 nanometers, and the optimal density of pores for desalination is one pore for every 100 square nanometers.
The Oak Ridge scientists note that the current graphene membranes are “at least an order of magnitude higher than [that through] state-of-the-art reverse osmosis polymeric membranes.”
Read more about the use of graphene in water desalination here: http://www.cemag.us/news/2015/03/promising-results-using-graphene-water-desalination
Further reading: Bill Nye, Neil deGrasse Tyson Launch Kickstarter for Sun-powered Spacecraft: http://www.laboratoryequipment.com/news/2015/05/bill-nye-neil-degrasse-tyson-launch-kickstarter-sun-powered-spacecraft
Click here for the full text of Bill Nye’s commencement speech: http://time.com/3882613/bill-nye-graduation-speech-rutgers-university/
