Ending the Plastic Crisis with the Use of Orange Peels
By Marc AlessiPublished October 11, 2015By Marc Alessi, 10/11/15
Finally there is hope in sight to the end of the plastic crisis. Researchers at the University of Bath in the United Kingdom are discovering and perfecting methods of making plastic from orange peels. That's right, the fruit that serves as a source of vitamin C to millions of people every morning could also be used to end our reliance on crude oil for plastics.
Each year, over 70 million tons of Oranges are produced worldwide, but nearly 20 million tons of the oranges are wasted during orange juice production. Hiding in the peels of these oranges is a colorless liquid hydrocarbon known as limonene. Removing limonene from peels is already a common, but inefficient process. In fact, limonene, which gives oranges and lemons the classic citrus scent, is found in perfumes, cleaning products, and foods. The process for extracting this limonene was long, energy intensive, and didn't result in high quality products needed for the production of plastic. At the University of York in the United Kingdom, a new microwave extraction technique was implemented. The orange peels were placed in an organic solvent and put in a microwave for 30 minutes. The water molecules would boil and rupture, allowing the limonene to leach out. "The results are favorable," says Marc Hutchby, a researcher at the University of Bath, "the process is much faster, less energy intensive, produces a higher quality of limonene, and in a yield twice as good as conventional methods." Because of this advancement in technology limonene may now have a new purpose: acting as a building block for the polymer industry.
Unfortunately, it's not all good news. Limonene as a bio-based chemical is still only a dream that must be pushed to reality. As of now, there are no commercial products on the market that contain limonene-based plastics. And even if all of the currently available limonene from citrus waste was made into polymers, it wouldn't impact global levels of plastic production as much as one would hope. Nonetheless, any sustainable practice that leads to the end of the world's reliance on crude oil for plastic is an improvement. Just last year a study showed that nearly 270,000 tons of plastic is floating in our oceans, killing and changing entire marine ecosystems. Whatever we can do to reduce plastic consumption will benefit later generations.
Improvements in the limonene extraction technology would not only lower the amount of wasted millions of tons of oranges, but cut down on plastic pollution and allow for a more sustainable world. It is important that we continue to develop methods and technologies in an effort to make our planet more sustainable. The creativity of scientists must not be hindered, especially in cases where orange peels may hold the key to solving a global-scale problem.