Will chemical recycling close the loop for plastics?

Circularity is one of the megatrends featured in Highlight Sessions at ACHEMA Pulse. Can the plastics industry succeed in reusing its products in a reasonable way? And what types of recycling are there anyway?

We talked to Dr Andreas Kicherer, Director Corporate Sustainability at BASF.

Is chemical recycling the ultimate answer to plastic waste?

• __I would not say that it’s the ultimate answer, and further on I don’t think that any single technology can be the ultimate answer to the plastic waste challenge. To cope with this challenge and create a circular economy, we need every available solution: This includes, for example, long-lasting products that can be reused. If reuse is impossible, we need mechanical recycling, chemical recycling and even energy recovery as well. If somebody says that they have the ultimate solution to plastic waste, I personally would have serious doubts.

Why don’t we just recycle everything chemically? If you break the polymer down anyway, you need not worry about any impurities.

• __Firstly, there are excellent mechanical recycling schemes, such as for polyethylene terephthalate (PET) bottles, in Germany and other European countries. If you can transform a water bottle into a water bottle again – what’s not to love? The other reason is that you cannot recycle all types of plastics chemically. The PET molecule, for example, contains oxygen, but pyrolysis works only in an oxygen-free environment. Mechanical recycling is by far the best option in this case.
  
  However, there are many other plastic waste streams with a mix of all sorts of polymers, e.g., leftovers of municipal plastic waste sorting, that are very well suited for chemical recycling. Nowadays, these waste streams are usually energetically recovered. Bringing them back into the loop through chemical recycling is the better option. All in all, chemical recycling can complement mechanical recycling. We should always chose the most eco-efficient recycling option.

Is chemical recycling applicable in devel-oping countries where waste collection and separation isn’t all that elaborate?

• __The first commercial plants are located in Europe. Nevertheless, we are looking for options to also use the technology in other regions in the future. However, it is important that a functioning waste collec-tion infrastructure exists or is established.
  
  At BASF, we are strongly committed to increase the amount of plastic waste that is collected and recycled and are therefore engaging in various projects and initiatives that strengthen the idea of the circular economy and prevent plastics from enter-ing the environment. For example, BASF is a founding member of the Alliance to End Plastic Waste, and we take that commitment seriously.

How about the production of pyrolysis oil? Have you changed your supply chains, and have there been new business alliances along the way?

• __Collecting and recycling waste is definitely not our core business, thus we have partners who operate pyrolysis plants. These new partnerships are very intense, to the extent that we deploy experts to support them with our technological expertise. Our Norwegian partner Quantafuel, for example, turns mixed household plastic waste into pyrolysis oil. However, the raw pyrolysis oil is not yet suitable for chemical production. It’s much more like raw mineral oil, which you can’t send directly into a chemical plant straight from the oil well either. This is where BASF’s expertise comes in. We support our partner Quantafuel in developing suitable catalysts to purify the pyrolysis oil. Only then, the oil fulfils the specifications that it needs to be used in our chemical plants.

Chemical recycling is criticised as greenwashing because it is very energy intensive. What do you answer to this?

• __Currently, the commercial pyrolysis plants run at an efficiency of 71 %. That means that 71 % of the plastic waste is converted to oil, and we expect to raise the efficiency to 75 % to 80 %. The remaining 20 % is turned into a gas that fuels the whole pryrolysis process, so we need almost no external energy for that.
  
  And by the way: Chemical recycling can also contribute to the reduction of CO₂ emission, because the pyrolysis of mixed plastic waste emits 50 % less carbon dioxide than its incineration. This is the conclusion of a life cycle assessment (LCA) carried out by the consulting company Sphera on behalf of BASF, which was reviewed by independent experts.

You explained very well that chemical recycling is only part of the whole plastics world.  What would be your guess about the share of chemical recycling ten years from now?

• __I do not think that it will be dominating. It depends on whether the regulatory framework supports chemical recycling and in the EU that’s definitely the case. I think that the rate of chemical recycling in 2030 could be 20 to 30 %.

Questions asks by Kathrin Rübberdt