A Montreal-based startup company is partnering with Total SA's Polymers Business unit to develop a solution-based technology to recycle polystyrene.
Polystyvert and Total said May 2 that they will combine Polystyvert's technology with Total's expertise in industrial-scale dissolution and polymerization to recycle household PS.
Polystyvert's system involves dissolving PS present in scrap, then transporting the solution to a facility that would drive off the solvent to recover clean PS resin. The approach is especially attractive for expanded PS foam since the solution would be much more economical to transport. Polystyvert claims the resultant PS recyclate would be cleaner than PS resin recovered by mechanical means, now the main route for recycling PS.
"In 2017, Total performed three successful test runs with post-consumer recyclates incorporated in virgin polymer via dissolution and polymerization," said Jean Viallefont, Total's vice president of polymers in Europe, in a news release. "Working with Polystyvert to tackle household post-consumer waste is the next logical step for Total."
The use of solvents to recover PS has been posited for at least 20 years. A liquid chemical called d-limonene derived from citrus fruit peels has received the most attention, it was the subject of a U.S. patent filed in 1992 by Claudia Iovino., who became president of a startup called International Foam Solutions Inc. in Delray Beach, Fla.
However, Polystyvert's system uses cymene as the solvent. Cymene occurs naturally in cumin and thyme spices and can be made by industrial processes. For instance, It can be a byproduct of sulfite wood pulping and it can be made from oil-based petrochemicals.
A Polystyvert spokesman stated in an email that a demonstration plant will be operating in Montreal in June with capacity to recover 275 pounds of PS per hour. Cymene was chosen as the solvent because it is not very hazardous and is stable enough to withstand numerous distillations in the PS recovery step. These attributes offer economic and technical advantages, the spokesman said.
"Collaborating with Total on household waste will accelerate the industrial development of our technology for global markets and demonstrate its suitability to address any type of polystyrene stream," Polystyvert founder and CEO Solenne Brouard said in a news release.
Brussels-based Total is a styrene and PS producer. Its U.S. petrochemicals subsidiary is based in Houston.