Recycling and Toxic Waste: Perfect Chemistry
At first glance, it looks like a moonshine still. There’s a big container with a long pipe sticking out the top and a tube jutting out the side and into a bottle. When the liquid inside is heated, the vapors boil up the pipe until, reaching the right temperature, liquid begins to drip from the tube into the bottle.
In reality, this still is much larger than one that makes moonshine, and the liquid pouring off is a bit more toxic than white lightning. Just ask Susan Setty. She’s the one who designed the system to recycle the solvents used by her employer, LyondellBasell Industries, a petrochemical company in Cincinnati where she worked as a chemist.
Setty has been a lot of things in her career since graduating from Xavier in 1974 and 1975 with bachelor’s and master’s degrees in history. She was first a teacher and then a mom, and then she became a chemist to help pay for her children’s Catholic school tuition.
When her temp job in a Procter and Gamble laboratory testing beauty products exposed her to chemical analysis, she went back to school to study chemistry and learned how to do gas chromatography. That led to a job with LyondellBasell, where she learned how to do TREF—temperature rising elution fractionation—a complex process that uses temperature to break down polymers into their individual components.
“My boss would bring me a piece of plastic and tell me to find out what it’s made of,” she says. She would dunk it into benzine solvent and heat it until it separated into its basic components—crystalline, semi-crystalline and rubber. The tests use up to 30,000 milliliters of benzene per week, creating a lot of waste that costs more to dispose of than to buy new.
So she designed a customized recycling system for her lab and found a company in New Jersey to build it. The solvent is heated until the chemicals burn off one at a time, coming off at different temperatures. All are captured in individual containers before reusing. The system was a win-win for the company because it assures a continuous supply of purified solvent for testing and reduces the amount of waste solvent. The company recouped the $100,000 cost of the recycling system in the first year alone and sends less waste to the landfill. That’s a win worthy of a champagne toast.