There are ways to make greener plastic besides making it from corn. On Tuesday, IBM’s Almaden Research Center and Stanford University announced a new line of organic catalysts that they say could revolutionize the green plastics industry by giving it a set of tools to build up — and break down — plastics in a more environmentally friendly and energy efficient way. While these new organic catalysts are limited to the lab right now, Saudi Arabia’s King Abdulaziz City for Science and Technology (KACST) wants to try a pilot plastics recycling plant with IBM and Stanford’s catalysts that could break down polyethylene terephthalate, or PET — the plastic found in milk bottles, polyester and many other consumer and industrial goods — into its starting components, and rebuild it as a whole new range of plastics. (Oh, and it could work for bio-based plastics, too.)
“We can apply this and rip polymers, which otherwise would have gone into a landfill, back into polymer-grade monomers,” is how Jim Hedrick, IBM’s lead scientist on the effort, described it to us. Monomers are the starting components of plastics, mostly petrochemical-based, though the share that is coming from plant-based materials is increasingly growing. Polymers are the PET, PVC, polystyrene and other forms of plastic we all know and (gulp) love.
The IBM/Stanford work on organic catalysts is aimed at replacing, or augmenting, a line of metal oxide or metal hydroxide catalysts now used in a step of the polymer-making process known as ring-opening polymerization. These traditional organometallic catalysts work well for this, but can leave heavy metals behind that have to be removed or left as contaminants in the plastic. In fact, IBM’s research started as a search for an organic catalysts that could be used in microelectronics manufacturing without leaving trace metals that shorted circuits. Being able to make plastic without nasty heavy metal residue also opens up medical uses for the research, Hedrick noted.
Plastic recycling is another angle to the discovery, Hedrick said. If the new organic catalysts can polymerize, or put plastics together, they can also de-polymerize, or take them apart. Not only that, but they can do it at room temperature — today’s chemical plastic recycling methods need high temperatures, and thus energy, making them cost-prohibitive in most cases. That’s why today’s PET recycling is overwhelmingly mechanical in nature, which means shredding up old PET and mixing it in with fresh PET, Hedrick explained.
The work in Saudi Arabia is aimed at reducing PET to its starting materials in this low-energy manner, he said. It could also be designed to yield other materials that might have higher value than PET and be harder to make, he said — besides working at room temperature, the new organic catalysts have high “selectivity,” meaning they can be applied to yield very specific, standardized plastic products.
Just how long it might take to get a pilot plant up and running — as well as how much it might cost — Hedrick wasn’t able to say just yet. How well the new technology might compete with traditional ways of making plastic may depend in part on the growth of government mandates and private initiatives into greener plastics, he noted.
How green is plastic getting? While there’s no doubt that more eco-friendly plastic is in demand, it’s still a tiny share of the market, according to Frederick Scheer, CEO of bioplastics maker Cereplast. The market for plant-based resins used to create plastics, for example, is expected to grow from about $1 billion in 2007 to about $10 billion in 2020, he said — but that’s out of an overall resins market of about $2.5 trillion in 2009. Cereplast is now working on expanding bioplastics from their traditional place in the plastic bags and spoons category to more durable plastics, such as cellphone cases.
Other companies are tackling different angles on the green plastic business. Novomer, a startup that uses recycled carbon dioxide and carbon monoxide to make polymers and plastics, raised $14 million in August, and algae-to-ethanol startup Algenol Biofuels told the New York Times in June that it was working with Dow Chemical on a plant to make ethanol, at first for fuel, but later as a replacement for natural gas in plastics making.
No doubt the more than 80 members of the Biodegradable Products Institute, among them BASF, DuPont, GeorgiaPacific, Dow and Cargill’s bioplastic subsidiary NatureWorks, are interested in ways to make their products cheaper, stronger and cleaner. But beyond the work of a few other university researchers, Hedrick isn’t sure if the big plastics companies are working on organic catalysis — or, as he speculates, “If they are, they’re not telling us.”
Image courtesy of NatureWorks.