Molecular Characterization of a Mixed Plastic Pyrolysis Oil from Municipal Wastes by Direct Infusion Fourier Transform Ion Cyclotron Resonance Mass Spectrometry

Abstract

Plastic wastes cause well-known harmful effects for the environment and contribute to the depletion of landfill sites. Pyrolysis oil produced from plastic waste materials is considered as an important source to produce monomers, fuel, and chemicals that both circumvent some of the environmental concerns associated with nonrenewable fossil resources and alleviate waste disposal concerns. In order to improve conversion and valorization processes, an advanced molecular description is essential. Such as petroleum crude oils, plastic pyrolysis oils are complex mixtures composed of thousands of chemical species covering a wide range of masses and polarities. Molecular characterizations require the use of high-resolution instruments such as Fourier transform ion cyclotron resonance mass spectrometers. In this study, we report the characterization of plastic pyrolysis oil by the main atmospheric pressure ionization: electrospray ionization (ESI) in positive and negative modes (±), atmospheric pressure photoionization (APPI) in positive mode (+), and atmospheric pressure chemical ionization (APCI) in positive mode (+). A large predominance of hydrocarbon compounds was observed in APPI (+) and APCI (+). Moreover, the use of both sources highlighted different types of molecules such as paraffins, diolefins, and more particularly triolefins, which have not yet been reported. Basic and neutral nitrogen-containing species (N1 and N2 classes) were highlighted by ESI (+) and ESI (−), respectively. Oxygen-containing species O1–O4 were identified principally by ESI (−) but also in APPI (+) and APCI (+) and attributed as carboxylic acid and alcohol functional species. The same functionality of oxygen is founded in N x O y compounds observed in ESI (+) and ESI (−).

Review on Evolved Gas Analysis Mass Spectrometry with Soft Photoionization for the Chemical Description of Petroleum, Petroleum-Derived Materials, and Alternative Feedstocks

“… Other plastic additives, such as flame retardants, colorants, or plasticizers, are expected to largely contribute to alternative feedstock pyrolysis oils. Recently, nitrogen-containing species in plastic pyrolysis oils were reported at the molecular level and linked to additives, such as hindered amine light stabilizers (HALS) …”

“…Recently, nitrogen-containing species in plastic pyrolysis oils were reported at the molecular level and linked to additives, such as hindered amine light stabilizers (HALS). 157 Waste tires are considered as an important source for recycling and act as a substantial alternative feedstock. This waste made of natural and synthetic rubber, carbon black, textile material, steel, sulfur, and additives can be thermochemically converted (pyrolyzed), generating tire pyrolysis oils having a comparable calorific value to petroleum.…”

Speciation and Semiquantification of Nitrogen-Containing Species in Complex Mixtures: Application to Plastic Pyrolysis Oil

“… 12 , 25 , 28 Specifically, in a previous study, the presence of nitrogen-containing species in the plastic pyrolysis oil was highlighted by electrospray ionization (ESI). 29 Nitrogen-containing species form due to the presence of antioxidant additives such as hindered amine light stabilizers (HALS) and nitrogen-containing polymers such as polyamides in the plastic waste. These nitrogen-containing molecules are of particular interest because they can act as catalyst poisons during refining processes.…”

“…Each was previously characterized using different analytical methods such as gas chromatography (GC), ,− infrared spectroscopy (IR), nuclear magnetic resonance (NMR), and mass spectrometry (MS). ,, Because pyrolysis oil is of particular interest for the recovery of monomers, the material chosen in this study is a pyrolysis oil produced from real municipal wastes made up of different plastic types. Owing to the high molecular complexity of such samples, the necessity of using very-high-resolution mass spectrometry such as Fourier transform ion cyclotron resonance (FTICR) to characterize plastic oils has been demonstrated. ,, Specifically, in a previous study, the presence of nitrogen-containing species in the plastic pyrolysis oil was highlighted by electrospray ionization (ESI) . Nitrogen-containing species form due to the presence of antioxidant additives such as hindered amine light stabilizers (HALS) and nitrogen-containing polymers such as polyamides in the plastic waste.…”

Virtual Special Issue of Recent Advances in Analysis of Fuels and Products by Advanced Mass Spectrometry

“…The oxidation products are monitored with FT-ICR MS, and increased oxygenated compounds are observed with increased oxidation time and biodiesel content. Mase et al10 characterized oil generated by pyrolysis of plastic waste with FT-ICR MS. A large predominance of hydrocarbon compounds, including paraffins, diolefins, and triolefins, is found. Basic and neutral nitrogen-containing species (N 1 and N 2 classes) and oxygen-containing species O 1 −O 4 are also found.…”