PTQ Q2 2025 Issue

Advancing adoption of chemical recycling

Processing waste plastic pyrolysis oils through hydrocarbon processing assets

Artem D Vityuk BASF Corporation

P lastic waste pollution is a major global issue. As the chemical industry is increasingly focused on transi- tioning to more sustainable value chains, technologies emerge to advance circularity in raw materials, intermedi- ates, and finished products. Plastics and respected deriva - tives have long become a key growth engine of the modern chemical industry. With a global production volume of more than 400 Mt in 20221 and an estimated c ompound annual growth rate (CAGR) of 4%, total plastics throughput will reach 590 M tons by 2050.2 While varied by country, the growth trend is mostly reflec - tive of economic development of the region and respective consumption patterns. The high versatility of properties and functions, in conjunction with favourable costs, made most plastics virtually irreplaceable for modern society. At the same time, recycling rates have been lagging behind, trend- ing globally at only 9%.3 About 79% of all plastics made are estimated to be landfilled or scattered across global nature ecosystems.3 Insufficient recycling combined with the absence of alter - native upcycling methods that would repurpose or process plastics into other useful goods or materials resulted in a tremendous plastic waste issue. There are estimates putting the accumulated amount of plastics produced globally since 1950 at 8.3 billion tons,4 causing exponentially compounding environmental problems and threatening ecological domains. Other than major potential economic downturns, there are no long-term conceivable factors that would substantially limit global plastic waste volumes unless the industry, sup- ported by proper regulatory policies, completely re-evalu- ates the value chains and adopts new technologies to boost circularity. The key technologies that support this transition are mechanical and chemical recycling. While increasing mechanical recycling rates is believed to be instrumental in reducing plastic waste, a meaning- ful impact would only be achieved if chemical recycling is deployed at scale.5 Among chemical recycling technologies, pyrolysis gained the most attention as a scalable and effec- tive method to process waste plastics. Pyoil purification and upgrading Pyrolysis is a thermochemical process that converts plastics into a hydrocarbon-based oil called pyrolysis oil or pyoil. Its

value is recognised as the substitute for fossil-based feed- stocks across various industrial petrochemical processes contributing to new plastics production. Some of the advan- tages of pyrolysis include the ability to accept mixed waste plastics streams, composite plastics, and high complexity waste, such as from electronics. Nevertheless, there are also challenges. A typical pyoil is often contaminated and features a range of impurities, severely limiting its further use as a petrochemical feedstock. Efficient purification and upgrading of raw pyoil are seen as a prerequisite to enable industry-wide adoption of chemical recycling. In general, pyoil quality is dependent on the com- position and types of plastic waste fed into the process and the design of the pyrolysis technology.6 , 7 It is imperative to understand that there is no standard grade of a pyoil, even with loosely defined specifications. As the chemical recycling industry continues establishing itself, such standards are yet to be agreed upon by produc- ers and downstream off-takers. The current market offers what could be described as pyoil grades featuring a varying extent of contamination and diverse compositions. Against this backdrop, the natural question arises regarding the optimal processing strategies for petrochemical and refining industries towards value maximisation while transitioning to circularity in their manufacturing chains. There is clearly no unified approach. What is important to understand is that a) a rapid step change in adopting the circularity principles in base petrochemicals should not be expected, and b) this transition will require close integration of traditional refining and petrochemical assets. The tran - sition is expected to be gradual by early adopters of pyoils experimenting with a range of technologies available, includ - ing core refining assets. Parameters Pyoil boiling range Pyoil boiling range is a critical parameter affecting the choice of a potential downstream processing technology. There are well-grounded reasons to refer to the naphtha cut of the pyoil as being the most valuable platform for producing the key building blocks of most plastics and composites, includ- ing ethylene, propylene, and benzene, toluene and xylenes (BTX).

PTQ Q2 2025