Opportunities and challenges for the application of post-consumer plastic waste pyrolysis oils as steam cracker feedstocks: To decontaminate or not to decontaminate?. (1st February 2022)

• Record Type: Journal Article
• Authors: Kusenberg, Marvin; Eschenbacher, Andreas; Djokic, Marko R.; Zayoud, Azd; Ragaert, Kim; De Meester, Steven; Van Geem, Kevin M.
• Is Part Of: Waste management. Volume 138(2022)
• Page Start: 83
• Page End: 115
• Publication Date: 2022-02-01
• Subjects: Thermochemical conversion -- Chemical recycling -- Characterization -- Steam cracking -- Contaminants -- Upgrading; AAS Atomic absorption spectroscopy -- ABS Acrylonitrile butadiene styrene -- AED Atomic emission detector -- ASTM American Society for Testing and Materials -- ASR Automotive shredder residue -- ATR Attenuated total reflection -- CHNS/O Carbon, hydrogen, nitrogen, sulfur / oxygen elemental analyzer -- CIC Combustion Ion Chromatography -- CSTR Continuous stirred tank reactor -- ECD Electron capture detector -- EDXRF Energy dispersive X-ray fluorescent spectroscopy -- EPA Environmental protection agency (US) -- EU European Union -- FBP Final boiling point -- FCC Fluid catalytic cracking -- FIA Fluorescent indicator adsorption -- FID Flame ionization detector -- FTIR Fourier-transformed infrared -- GC Gas chromatography -- GC × GC Two-dimensional gas chromatography -- HDPE High-density polyethylene -- HIPS High impact polystyrene -- HPLC High performance liquid chromatography -- IBP Initial boiling point -- ICP Inductively coupled plasma -- Incl. Including -- JIS Japanese industrial standards -- LC Liquid chromatography -- (L)LDPE (linear) low-density polyethylene -- LOD Limit of detection -- LOQ Limit of quantification -- MAPD Methyl acetylene and propadiene -- MPO Mixed polyolefins -- MS Mass spectrometry -- NCD Nitrogen chemiluminescence detector -- ND Not detected -- NMR Nuclear Magnetic Resonance -- OES Optical emission spectrometry -- PA Polyamide -- PAH Polyaromatic hydrocarbons -- PET Polyethylene terephthalate -- PFO Pyrolysis Fuel Oil -- PIONA Paraffins, (iso-) paraffins, olefins, naphthenes, aromatics -- PMMA Polymethylmethacrylate -- PP Polypropylene -- ppb Parts per billion -- ppm Parts per million -- PS Polystyrene -- PTFE Polytetrafluoroethylene -- PUR Polyurethane -- PVC Polyvinylchloride -- PVDC Polyvinylidene chloride -- SCD Sulfur chemiluminescence detector -- STR Stirred tank reactor -- TCD Thermal conductivity detector -- TGA Thermogravimetric analysis -- ToF Time-of-flight -- WEEE Waste electrical and electronic equipment; Hazardous wastes -- Periodicals; Refuse and refuse disposal -- Periodicals; 363.728
• DOI: 10.1016/j.wasman.2021.11.009
• Languages: English
• ISSNs: 0956-053X

Abstract

Graphical abstract: Highlights: Contaminants determine the chemical recycling potential of pyrolysis oils. Pyrolysis oils contain more and different contaminants than fossil feedstocks. Contaminants cause corrosion, process fouling and downstream catalyst poisoning. The main contaminants are nitrogen, oxygen, chlorine, iron, lead and calcium. Advanced analytical techniques and standardization are crucial. Abstract: Thermochemical recycling of plastic waste to base chemicals via pyrolysis followed by a minimal amount of upgrading and steam cracking is expected to be the dominant chemical recycling technology in the coming decade. However, there are substantial safety and operational risks when using plastic waste pyrolysis oils instead of conventional fossil-based feedstocks. This is due to the fact that plastic waste pyrolysis oils contain a vast amount of contaminants which are the main drivers for corrosion, fouling and downstream catalyst poisoning in industrial steam cracking plants. Contaminants are therefore crucial to evaluate the steam cracking feasibility of these alternative feedstocks. Indeed, current plastic waste pyrolysis oils exceed typical feedstock specifications for numerous known contaminants, e.g. nitrogen (∼1650 vs. 100 ppm max.), oxygen (∼1250 vs. 100 ppm max.), chlorine (∼1460 vs. 3 ppm max.), iron (∼33 vs. 0.001 ppm max.), sodium (∼0.8 vs. 0.125 ppm max.) and calcium (∼17 vs. 0.5 ppm max.). Pyrolysis oils produced from post-consumer plastic waste can only meet the current specifications set for industrial steam cracker feedstocks if they are upgraded, with hydrogen based technologies being the most effective, in combination with an effective pre-treatment of the plastic waste such as dehalogenation. Moreover, steam crackers are reliant on a stable and predictable feedstock quality and quantity representing a challenge with plastic waste being largely influenced by consumer behavior, seasonal changes and local sorting efficiencies. Nevertheless, with standardization of sorting plants this is expected to become less problematic in the coming decade.