How Effective Is Chemical Recycling for Plastic Waste?

Chemical recycling can reduce the quantity of plastic that ends up in landfills, hence lowering the risk of dangerous chemicals being released into the environment.

FREMONT, CA: Plastic, which takes thousands of years to degrade and thus pollutes ecosystems worldwide, is a widespread environmental scourge. For decades, efforts to recycle waste material have been a staple of local and national government policy but insufficient.

Plastic is difficult to recycle precisely because it possesses an advantageous property: extreme durability. This means that most plastic ever produced is still physically present in the environment.

It enters soil, waterways, and food chains via the bodies of animals and humans. It is toxic to human and animal health and may be wreaking havoc on the planet's inhabitants and ecosystem.

Along with its long life in the environment, plastic's durability makes recycling notoriously difficult. Today, only 9 percent of all plastic ever produced has been recycled.

The issue will not be resolved. Globally, over 380 million tons of plastic are produced each year. Today, 40 percent of plastic waste is disposed of in a managed landfill, 25 percent is burned in an incinerator, and 19 percent is illegally dumped. Only 16 percent of newly manufactured plastic waste is recycled.

Even recycled plastic waste and discarded items are frequently unable to be recycled effectively. Traditionally mechanical recycling processes require sorting, cleaning, shredding, melting, and remolding plastic into new products.

However, this technique produces a lower-quality material, and many uses, including food and medical packaging, continue to rely on virgin plastics obtained from fossil fuels. This is because polymer chains break down during the melting process, lowering the resulting materials' tensile strength and viscosity.

Each time plastic is recycled in this manner, the resulting material degrades. Eventually, plastic that has been recycled repeatedly becomes unusable.

Traditional mechanical plastic recycling requires substantial sorting and packing procedures that are both energy and labor-intensive. Businesses that operate traditional commercial-scale recycling plants frequently rely on government subsidies to stay afloat.

Chemical recycling may hold the key to resolving these issues. It requires significantly less waste sorting in advance and produces high-quality polymers suitable for high-end plastic applications.

Polymer chemistry—the branch of chemistry that studies plastics and their manufacture, characteristics, and properties—has recently become increasingly focused on chemical recycling.

Chemical recycling converts hard plastic back to the oil from which it was made, which can then be used to create new high-quality plastic products. Although the possibility of recycling plastic in this manner has existed for decades, it was previously unviable. This is due to the high energy requirements for most chemical recycling techniques proposed thus far.

When energy costs are included in the overall production cost, recycled material becomes prohibitively expensive for widespread use. New plastics derived from crude oil are often too inexpensive to pass up.

However, suppose a commercial-scale recycling plant results in economically viable chemical recycling. In that case, the benefits of this type of recycling will be applied to the broader issue of plastic pollution in the atmosphere.

Chemical recycling is capable of processing a variety of plastics simultaneously. This is a significant benefit, as much plastic waste is currently disposed of in landfills due to confusion about curbside waste collection, insufficient infrastructure, or the high relative cost of recycling small pieces of material.