Solution for more sustainable plastics: Neste RE™

For the production of renewable Neste RE, we are leveraging Neste’s proprietary NEXBTL (“Next generation biomass to liquid”) technology. NEXBTL enables us to turn bio-based oils and fats into pure hydrocarbons: fuels or feedstock for plastics and chemicals production. Waste and residue oils and fats, such as used cooking oil or waste and residues from vegetable oil processing, account for more than 90% of our annual renewable raw material inputs globally. 

Production of Neste’s renewable products has three steps: pretreatment, hydrotreatment and isomerisation. The output is a variety of renewable products from 100% renewable raw materials. 

Our oil refinery in Porvoo, Finland, is capable of co-processing renewable raw materials together with fossil crude oil. The output can replace conventional fossil raw materials for plastics such as fossil naphtha or propane without any concessions to quality. 

For co-processing, we are applying the mass balancing method: In the refinery, renewable raw materials – such as waste and residue oils like used cooking oil – are mixed with fossil crude oil. The output is a product consisting of both bio-based and fossil molecules. The exact composition of a specific batch may vary: It depends on the input ratio. 

Mass balancing concept is based on tracking the share of bio-based and fossil material inputs and allocating the respective bio-based content to the volumes of the manufactured products. 

Mass balancing is a useful concept when there is no difference in quality or performance of different materials used, as is the case with Neste RE. It allows for a gradual transition from fossil to non-fossil materials in the value chain. Once there is sufficient supply of non-fossil materials to run entire value chains just on non-fossil materials, mass balancing is expected to become less relevant.

The benefit of replacing fossil feedstock for plastics with renewable feedstock lies with the carbon footprint. Renewable feedstock consists of renewable carbon from the atmosphere that has been absorbed during biomass growth. When this carbon is later released back into the atmosphere, e.g. when plastic produced from renewable feedstock is being incinerated, it does not add additional carbon to the atmosphere. Instead, the carbon is part of the natural carbon cycle where carbon is continuously exchanged between biosphere and atmosphere.

Using Neste RE produced with renewable raw materials therefore comes with a significantly reduced carbon footprint over the use of fossil resources. 

For example, our life cycle assessment (LCA) shows a greenhouse gas emissions (GHG) reduction of more than 85% when renewable Neste RE feedstock from NEXBTL replaces fossil feedstock*. 

_{*Life Cycle Assessment on Environmental Impacts of Neste Renewable Polymers and Chemicals (30 June 2021)}

Today’s predominant plastic recycling technology is mechanical recycling. While it is a very efficient process, it relies on rather clean plastic wastes. Further, it also slightly diminishes the quality of the recycled material, leading to a finite amount of possible recycling cycles. Finally, there are also limitations in the applications that can be made from mechanically recycled waste plastic: The more sensitive the application (e.g. medical or food contact), the more difficult it becomes. For certain waste streams though, e.g. PET bottles, mechanical recycling is a very valuable and important approach to circular plastics. 

To produce recycled Neste RE, we are using a new technology: chemical recycling. While mechanical recycling maintains the polymeric structure of the plastics, chemical recycling works similar to a reset button. It turns the wheel back a little further by breaking up this structure and thus turns the plastic back into the raw material (hydrocarbons) it was made of.

The plastic waste we use as a raw material is liquefied by our suppliers, creating a liquid that to some degree resembles crude oil. Dedicated processes in our conventional oil refinery then remove various impurities and turn the liquefied waste plastic into high-quality feedstock for new plastics again. This feedstock, Neste RE consisting of pure hydrocarbons, is of virgin quality and can be turned into all kinds of plastics for varying applications. As of today, the liquefied waste plastic is co-processed in our refinery together with fossil crude oil, applying a mass balancing method. 

The advantages: with chemical recycling, we can recycle plastic waste that currently has no real use as it is considered hard to recycle with conventional means. At the same time, chemical recycling also leads to virgin-quality raw materials for new plastics, so there are no concessions to quality, purity or sensitivity versus plastics made from virgin raw materials: Chemically recycled feedstock can be used for all kinds of plastic applications, including sensitive ones like food-contact packaging or medical products.

While chemical recycling requires more effort and more energy than conventional recycling, it tackles different waste streams and turns them into a different output. That is why we consider mechanical and chemical recycling complementary technologies – and we will require both to tackle the plastic waste challenge.

Our independently verified life cycle assessment (LCA) shows that despite the efforts required, chemical recycling can contribute to improving the carbon footprint of plastics when it replaces the use of fossil resources and the incineration of plastic waste. In fact, GHG emissions can be reduced by more than 35% if recycled Neste RE replaces fossil feedstock and prevents plastic waste from being incinerated*. 

_{* Life Cycle Assessment on Environmental Impacts of Chemical recycling of waste plastic - Case Neste (October 2022).}