Chemical recycling of plastics is getting more backing from a major petrochemical maker. ExxonMobil has announced it will build a recycling plant at its Baytown, Texas, complex and deploy its technology around the world over the next 5 years.
The plant, scheduled to start up by the end of 2022, will use ExxonMobil technology to process 30,000 metric tons (t) of plastic waste per year into a feedstock that the firm can turn into chemicals again.
ExxonMobil isn’t disclosing technical details about its process, which it tested in Baytown earlier this year and has used to process 1,000 t of plastic waste so far. The process involves “taking sorted plastic waste directly into our existing facilities and process units,” a spokesperson writes in an email. “By leveraging our integration, we can skip some of the steps of other advanced recycling processes.”
Other plastics makers, including Dow, Sabic, and Chevron Phillips Chemical, have formed partnerships with companies that use pyrolysis to break down mixed plastic waste into an oil that can be refined and processed in steam crackers to make olefins and polyolefin plastics. ExxonMobil itself formed a partnership in March with a pyrolysis startup, Plastic Energy, which plans to build a 25,000 t per year plant at ExxonMobil’s site in Notre-Dame-de-Gravenchon, France.
ExxonMobil will make “circular polymers” with feedstock from a temporary facility in Baytown by the end of this year. Longer term, the company aims to use chemical recycling technologies to process 500,000 t of plastics annually by 2026. The company is considering projects at sites in the US, Canada, the Netherlands, and Singapore.
Anthony Palmer, vice president of circular plastics and sustainability at the consulting firm IHS Markit, says mechanical recycling—in which plastics are sorted by type, washed and repelletized—is the “first choice for recycling plastics” due to its lower capital costs, energy use, and carbon emissions compared to pyrolysis.
However, for multi-polymer materials, like packaging films, that aren’t made of a single type of plastic, pyrolysis can be a good option. “The process is a pretty forgiving one, and you can cut back on the separation of the upstream material,” Palmer says.
And for a company like Exxon, which is an experienced handler of hydrocarbons, taking a pyrolysis oil “and upgrading that to a naphtha-quality petrochemical feedstock is something that they have the core competency to do,” Palmer says.
Exxon’s announcement comes a week after rival Dow revealed a series of pyrolysis investments. It is working with Fuenix Ecogy to build a recycling plant in Weert, the Netherlands, that will have 20,000 t per year of capacity. Dow will use the output as feedstock at its chemical plant in Terneuzen, the Netherlands, where it will also test technology to purify pyrolysis oil with the engineering firm Haldor Topsoe.