New Method Makes Plastic Bottles from Plant Chemicals
A new chemical catalyst turns plant-derived chemicals into a key plastics ingredient that's usually made from petroleum.
CREDIT: From the County of Los Angeles Public Health
Many people have seen bottled water, chip bags and more advertise they're packaged in plant-derived plastic. They're rare, but they're out there. Here's a step that might help those greener packages become more commonplace. Chemists at the University of Massachusetts and the University of Delaware have created a new process to make a key ingredient in plastic bottles using chemicals derived from plants, instead of the usual petroleum. The new method is cheaper and more efficient than other, similar techniques scientists have come up with, the Massachusetts and Delaware researchers said in a statement. Their research appeared in the journal ACS Catalysis April 18.
The process creates a chemical called para-xylene, which is an important ingredient in the plastics that go into plastic bottles, frozen dinner trays, synthetic fibers in clothes and some car parts. Any recyclable plastic that has a #1 stamped on it is made from plastic that uses para-xylene. The U.S. used six million pounds of para-xylene in 1995, according to a University of Minnesota database.
The chemists designed a catalyst, or a chemical that speeds other chemical reactions, that ushers along the reaction that makes para-xylene. Most complex chemical reactions are actually a combination of several reactions, as the different chemicals in a mixture meet each other and combine differently. The tweaked catalyst reduces side reactions so that 75 percent of the plant chemicals that go into the process come out as para-xylene.
Catalysts like this are sure to be in high demand in the future. Though plant-derived products make up about one percent of plastics industry now, the Bioplastics Council expects the market to grow by 40 percent in three years, Grist reported.