Existing recovery methods evaporate mercury at high temperature, separating it from other materials in the bulbs. Parisa A. Ariya of McGill University and her colleagues instead use iron oxide nanoparticles to trap mercury at near room temperature without heating. The team broke open CFLs within a vessel that was connected to a chamber loaded with nanoparticles. As mercury vapor from the bulbs flowed into the chamber, it stuck to the nanoparticles. The team then used magnets to transfer the nanoparticles to an electrochemical reactor in which the researchers drove off ionic mercury species and reduced them to elemental mercury. Their prototype system recovered up to 85% of the mercury and required only 20 W of power, little enough for a small solar panel to provide. /articles/94/i17/Reclaiming-mercury-spent-fluorescent-bulbs.html 20160425 New process might offer a more energy-efficient alternative to current recycling methods Concentrates 94 17 /magazine/94/09417.html /departments/.html /collections/con.html Reclaiming mercury from spent fluorescent bulbs Science & Technology Melissa Pandika, special to C&EN In a new recycling process, magnetic Fe3O4 nanoparticles remove mercury vapor from spent fluorescent bulbs, followed by electrochemical separation to pull the mercury off the nanoparticles for reuse.
by Melissa Pandika, special to C&EN |
April 25, 2016