A new study presents a strategy that could change the fact that most plastics end up garbage trucks and then in landfills as waste that takes hundreds of years to disintegrate.
Plastic is widely used. Only 5% of old plastic in the US is really recycled, according to the National Renewable Laboratory (NREL) of the US Department of Energy. This is mostly due to the fact that plastics differ chemically from one another, making it more difficult and expensive to separate specific polymers. The environment and landfills frequently become clogged with these mixed plastics.
Now, a new study described a novel method that would enable us to recycle these plastics, which generally end up as waste and take hundreds of years to disintegrate. The study was published on Thursday in Science.
The study proposes a hybrid method to recycling that makes use of both chemical and biological processes to attempt and repurpose plastics. It was spearheaded by researchers at NREL as part of the Bio-Optimized Technologies to Keep Thermoplastics out of Landfills and the Environment (BOTTLE) Consortium.
According to the project’s director and senior research fellow at NERL Gregg Beckham, “there are relatively few options to deal with mixed plastics in terms of recycling them.” Without segregating the polymers or waste plastics, “we wanted to be able to turn mixed plastic waste into a single product.”
Mixed plastics waste “represents an enormous and largely unexplored feedstock for the creation of valuable products,” according to the research.
Three types of typical plastics were employed in this study:
All three were successfully oxidised and transformed, and they are all common parts of post-consumer plastic waste.
In order to transform the plastics into smaller molecules that are suitable for biological conversion, the team first utilised metal-catalyzed oxidation. According to a news release by co-author and researcher Lucas Ellis of Oregon State University, these molecules are best characterised as “smaller, physiologically friendly chemical building blocks.” This is required for the process’ following stage, feeding it to bacteria.
What is High Density Polyethlene?
The most popular name and abbreviation for high density polyethylene plastic is HDPE sheet plastic. This thermoplastic, which is noted for being both light and durable, is formed from a long chain of ethylene molecules (thus the poly in polyethylene). Due to its strength and weight, HDPE sheet has becoming increasingly popular as more businesses adopt sustainability measures. This is because it can reduce the amount of material needed to make and package goods.
It takes about 25 years for HDPE to decompose in an open environment. In a landfill, however, it can take between 200 and 500 years to decompose (depending on the conditions of the landfill).
What is Terephthalate?
Terephthalate is a type of plastic. It is also used as an ingredient in other plastics, especially those that need to be flexible.
It has chemical compound with the formula (HOOCCH(CH2)4CO)2.
It can take anywhere from 450 to 1,000 years for Terephthalate to fully disintegrate, depending on the type of environment it’s exposed to.
The average life span of Terephthalate is between 450 and 1,000 years.
What is polystyrene?
Polystyrene is a plastic that is used in the manufacture of everyday items, including cups, CD cases, and even the packaging for electronics. It’s also one of the most commonly recycled plastics in the world.
It’s made from polystyrene beads that are heated at high temperatures until they become a liquid. The beads are then cast into molds where they cool and harden into solid pieces.
Polystyrene is a petroleum-based plastic, which means that it cannot be completely recycled because its chemical composition makes it difficult to separate from other materials during the recycling process.
Polystyrene is not biodegradable and it takes a very long time to disintegrate. This type of plastic is made up of two types of polymers, styrene and butadiene, which are both synthetic organic compounds. It’s commonly used in packaging, insulation and construction materials because it’s inexpensive (although it can be recycled), durable, lightweight, water-resistant and easy to work with.
Polystyrene can take up to 100 years to completely break down in landfills—and even then, it won’t disappear completely.
The plastic that does eventually decompose will release toxic fumes into the air that can cause lung cancer or damage your nervous system if inhaled regularly over time