For years, scientists have been working on a way to biologically degrade PET plastic using specialized enzymes. The theory is that bio recycling will ultimately be more efficient and less costly than mechanical or thermal recycling. Now, a new report out of Germany seems to suggest that we are getting closer to a commercially viable bio recycling solution.
Scientists at Leipzig University have discovered an enzyme that breaks down PET plastic in record time. In the lab, this enzyme can facilitate decomposition of a PET water bottle in about 16 hours, at a rate of about 90%. That is phenomenal by any measure. The task now is to try it in a real world setting and see how well the enzyme works in terms of recycling.
Enzymes that Break Polymers
Plastic decomposition has long been a problem due to the very nature of the material itself. Plastics are formed when molecules are bonded together to create polymer chains. The good news is that the polymers are hard to break apart. That is what makes plastic so tough and resilient. The bad news is that those same strong bonds inhibit decomposition.
The scientists in Germany are focusing their efforts on enzymes capable of breaking the toughest polymer chains. Break those chains and the material decomposes. Do it quickly enough and you can compost large volumes of plastic in a manner efficient enough to make it worthwhile.
The interesting thing here is that PET plastic is the most recycled plastic in the world. We recycle it mechanically by chopping and shredding it into smaller pieces. PET can also be recycled thermally, which is to say it is melted down and reformed into new end products.
More Efficient Recycling
We ideally want a way of recycling all plastics that is as efficient as possible. Along with efficiency, maintaining the integrity of the recycled material also helps a great deal. Unfortunately, both mechanical and thermal recycling don’t accomplish either goal as well as we would like.
Mechanical recycling is efficient. Chopped and ground plastic is added to virgin plastic to make new products. Both grinding and melting reduces the material’s integrity to some degree, which is why manufacturers have to add recycled material to virgin plastic. It is difficult to manufacture with 100% recycled material.
Thermal recycling is less efficient when you consider the amount of energy required to do it. It also reduces material integrity. The goal of bio recycling is to increase efficiency without sacrificing integrity.
A Plastic Compost Heap
When scientists finally perfect bio recycling – and they will at some point – PET plastic bottles, food containers, etc. will be sent to plastic compost heaps where specialized enzymes will decompose them as if they were mulch or grass clippings. The decomposed material will we put back into the plastic stream where it will be used again.
How long will it be before bio PET recycling is commercially viable? No one knows. A few years doesn’t seem unreasonable. Now that scientists have identified an enzyme that can break down PET plastics in record time, the hardest part of the equation has been solved. Now it is a matter of making it work on a large scale.
Until that time comes, Seraphim Plastics will continue recycling baled PET plastic bottles. If you would like to know more about our recycling efforts, feel free to contact us. Also note that we recycle other kinds of industrial plastic waste as well.
If there is a market for your plastic waste, we will come out to your location to pick it up. There is nothing for you to do but store it until we arrive.