We all know that carbon dioxide (CO2)—a greenhouse gas emitted into the atmosphere through the burning fossil fuels—is a major culprit in global warming. This gas is also hugely abundant in oil shale deposits, where it is typically burned away by flaring, or sometimes captured and injected via deep wells into porous rock formations.
Companies have tried for years to incorporate CO2 into plastic, but could not make the process cost-effective. Now, however, several plastics manufacturers have found success in using CO2 in plastics—the trick was finding the right catalyst.
The U.S. Department of Energy (http://energy.gov/fe/articles/recycling-carbon-dioxide-make-plastics) recently reported the world’s first successful large-scale production of a polypropylene carbonate (PPC) polymer using waste carbon dioxide as a key raw material. The PPC polymer production run, conducted by Novomer in collaboration with specialty chemical manufacturer Albemarle Corporation in South Carolina, tested scale-up of Novomer’s novel catalyst technology. Requiring only minor modifications to existing Albemarle facilities, the run produced seven tons of finished polymer.
“The Novomer process uses a catalyst to create PPC polymers through the co-polymerization of CO2 and chemicals called epoxides,” states the Department of Energy. “The process results in polymers containing more than 40 percent CO2 by weight. The CO2-containing polymers can be tailored for applications with a broad range of material characteristics, from solid plastics to soft, flexible foams, depending on the size of the polymer chain.”
Novomer is positioning its new polymer technology to compete with conventional petroleum-based raw materials across a diverse range of applications, including flexible, rigid, and microcellular packaging foams, thermoplastics, polyurethane adhesives and sealants, and coating resins for food and beverage cans.
Another company—Newlight Technologies, a start-up based in California—has developed a bio-catalyst that allows it to manufacture plastic from methane emissions captured on dairy farms. As reported in the USA Today, (http://www.usatoday.com/story/news/nation/2013/12/30/plastic-from-carbon-emissions/4192945/), this unique bio-catalyst removes the carbon from a liquefied gas and converts it into a long chain plastic molecule. Newlight Technologies has produced a plastic called AirCarbon that closely resembles polypropylene. Plans are in the works to manufacture chairs, food containers, automotive parts, and cellphone cases from AirCarbon, which was selected as the "bio-material of the year" at the 2013 International Conference on Bio-based Plastics and Composites.
Global companies are also getting in on the act—according to Doug Smock on The Molding Blog (http://www.themoldingblog.com/2014/01/10/efforts-grow-to-harvest-waste-carbon-dioxide-to-produce-plastics/), Bayer Company has reported success in using carbon dioxide in plastics at an industrial scale. Bayer’s CO2 is harvested from flue gas at a power plant and liquefied for transportation.
“Bayer MaterialScience has been using the carbon dioxide since early 2011 to manufacture samples of polyols used to make polyurethane foam,” indicates Smock. “Bayer reports that the test foams are just as good as those produced with petroleum.”
Smock adds that Bayer plans to start industrial production next year—the first product will be a mattress made from carbon dioxide-based flexible foam.
This is all encouraging news and demonstrates how visionary leaders in government and the private sector are working hard to find innovative solutions to global production problems.
Conventional production of plastics such as polyethylene and polypropylene is heavily dependent on fossil fuels. When by-products like CO2 can replace up to half the mass of the plastic product, less petroleum is consumed and fewer greenhouse gases makes their way into the atmosphere—a good thing for the planet.
“Capital requirements and operational costs to produce the new polymers closely mirror conventional production costs, and the products demonstrate increased strength and environmental resistance relative to existing polymers,” says the Department of Energy. “Incorporation into existing formulations results in packaging foams with higher tensile strength and load-bearing capacity, and adhesives and coatings with improved adhesion, cohesive strength, and “weatherabilty” properties, such as UV- and water- resistance.”