Evonik is developing solutions to support the chemical recycling of plastics, focusing on improving the quality of pyrolysis oil. The company offers specialized catalysts and adsorbents designed to remove impurities that may hinder the further use of this feedstock in petrochemical facilities. In the pyrolysis process, plastic waste is broken down at high temperature and in the absence of oxygen into simpler chemical compounds. The main product of this process is pyrolysis oil, which can supplement fossil feedstocks such as naphtha obtained from crude oil. This feedstock is then sent to steam crackers, where the basic compounds for manufacturing new plastics are produced, including ethylene and propylene.
According to the company, pyrolysis oil often contains impurities such as chlorine, nitrogen or silicon. Their presence can reduce the efficiency of steam crackers and affect the operational safety of the installations. Hendrick Rasch, responsible for Circular Packaging and Plastics Recycling in Evonik's Next Markets program, states: "Cracker operators apply strict quality standards to the feedstocks they use. This is exactly where our products come in. They help to significantly improve the quality of pyrolysis oil."
Evonik reports that it began work on pyrolysis oil purification technologies several years ago, using its experience in petrochemicals and feedstock processing. Within the Purocel product line, the company currently offers adsorbents developed specifically to remove impurities from pyrolysis oil. One of the key solutions is Purocel 505, which combines two process stages. First, in a catalytic reaction, chlorine atoms are separated from larger molecules, and then the resulting hydrogen chloride is bound. According to the company, this technology makes it possible to remove up to three times more chlorides from pyrolysis oil than conventional solutions.
Adsorption and hydrotreating
For applications with higher requirements, Evonik complements the adsorption process with hydrotreating. In this process, hydrogen reacts with the remaining impurities, converting them into volatile compounds. The company also states that, in order to further conserve resources, it uses recycled Purocel H catalysts at this stage.
In addition to chemical solutions, the company also offers modular systems intended for integration with existing facilities. Under Rocket Technology, Evonik supplies pre-configured column modules containing adsorbents such as Purocel 510. These units can be flexibly connected to both pyrolysis plants and steam crackers, which is intended to enable effective purification without significant capital expenditure and without prolonged downtime.
As Hendrick Rasch assesses: "Our solutions show how technological innovation can advance the circular economy. We are convinced that chemical recycling is one of the key pillars of a sustainable plastics economy."
The role of chemical recycling
The company points out that recycling contaminated and unsorted plastic waste remains a significant challenge. Mechanical recycling remains a well-established method for clean waste streams such as PET bottles. However, a substantial share of plastic waste consists of mixed and contaminated materials that are difficult to process by mechanical methods. In such cases, chemical recycling is used.
Evonik also points to growing global demand for chemical recycling, supported by the regulatory environment. The company positions itself as a system partner for industry and declares an offering of solutions tailored to different needs, from small-scale pyrolysis plants to large petrochemical complexes.
According to the company, the technologies under development are intended not only to support the circular economy, but also to strengthen the resilience of the industry. The use of pyrolysis oil is intended to reduce dependence on fossil resources, lessen environmental impact and improve security of supply.
