Waste sulfur could see new life due to a chemical process discovered recently by University of Arizona scientists. The lightweight plastic they created can be used to enhance lithium sulfur batteries and improve the range of electric cars or be used in optical systems.
“We’ve developed a new, simple and useful chemical process to convert sulfur into a useful plastic,” lead researcher Jeffrey Pyun said.
Lithium sulfur batteries (Li-S) are much more efficient than current lithium ion versions because they’re both lighter and cheaper. The new plastic is made of sulfur that’s left over from the refining of natural gas and oil – so much that it outstrips the current need for it, and there are yellow mountains of the element deposited at some refineries.
Lead researcher Jeffrey Pyun and his colleague Jared Griebel, a UA chemistry and biochemistry doctoral candidate, found 20 chemicals most likely to polymerize sulfur and tested them one by one. The first one worked, and “nothing else thereafter,” said Pyun.
The two scientists named their process “inverse vulcanization,” as it needs mostly sulfur with a small amount of the additive they’ve discovered. Vulcanization is the chemical process that makes rubber more durable by impurifying it with sulfur.
The point they’ve touched with the invention is the durability of current experimental lithium-sulfur batteries, whose cathodes crack after a small number of recharges (they’re made with pure sulfur). The specific capacity is also high – 823 milliamps per gran at 100 recharging cycles.
The international team led by the two U.S. researchers is now aiming towards making the plastic work for optical applications, too.