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The increasing demand for lightweight materials with exceptional stability and durability has resulted in a significant rise in fiber-reinforced plastic (FRP) production. These materials find applications in various fields. However, the exceptional properties and diverse compositional range of FRPs pose challenges to conventional recycling strategies. Pyrolysis has emerged as a highly promising approach for separating the fibers from the polymer matrix. In this study, we employed thermal analysis coupled with high-resolution mass spectrometry to investigate the pyrolysis process. Representative FRP showed a starting decomposition temperature of 300 °C and bisphenol A, styrene, alkenes, and phenols could be identified. The identified parameters were used to operate a pilot plant with a capacity of up to 50 kg/h FRP, and reactor products were directly analyzed with soft photoionization mass spectrometry. The findings demonstrated good agreement between the pilot plant results and laboratory experiments, particularly for smaller compounds (m/z<200). The non-condensable fraction showed a range of 17 to 22 MJ/m 3 as lower heating value. Analysis of the recovered fibers (diameter between 6.20 and 8.05 μm) revealed residual coke, but no toxic fibers were detected, according to the World Health Organization's definition. Yet, the organic coating of the fibers contained small amounts of potentially harmful PAHs. A toxicological assessment using a multicellular in vitro model confirmed the low hazardous potential of the recovered fibers. The findings contribute to developing sustainable and environmentally friendly recycling strategies for FRP while addressing important aspects related to the safety and toxicological implications of the resulting chemicals and fibers., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023. Published by Elsevier Ltd.)

A combined thermogravimetry/differential scanning calorimetry device (TG/DSC) was coupled to single photon ionisation mass spectrometry (SPI-MS) for evolved gas analysis (EGA). Single photon ionisation (SPI) was performed with a new type of VUV light source, the so called electron beam pumped rare gas excimer lamp (EBEL). SPI does not fragment molecules upon the ionisation process. Thus the molecular mass signature of the evolving gases from thermal composition of carbonaceous material can be directly on-line recorded. In this work the thermo-analytical data and the SPI-MS information on the released organics is presented and discussed for various samples. Namely biomass (soft and hard wood), fossil fuel (crude oil and coal) as well as a complex polymer (ABS) are investigated. The general potential of hyphenating thermal analysis and soft photo ionisation mass spectrometry (EBEL-SPI-MS) for fundamental and applied research and material analysis is discussed. [ABSTRACT FROM AUTHOR]

Abstract: Three different tobacco samples (Burley, Virginia, and Oriental) were thermally desorbed at varying temperatures (190, 250, and 310°C) and the evolved gas phase at every temperature step has been analyzed applying single photon ionisation (SPI)-time-of-flight mass spectrometry (TOFMS) and resonance enhanced multiphoton ionisation (REMPI)-time-of-flight mass spectrometry. These soft and selective ionisation techniques allow fast and comprehensive on-line monitoring of a large variety of aliphatic and aromatic substances with almost no fragmentation of molecular ions. Many oxygen containing compounds could be detected such as phenol, hydroquinone, and (vinyl)guiacol along with unsaturated hydrocarbons and nicotine. In addition, with REMPI a large variety of PAH are accessible. Different tobacco types yield slightly distinguished mass spectra. By utilizing statistical tools (Fisher criterion and PCA) the three tobaccos can be discerned rather rapidly from each other and possible marker compounds for a given tobacco can be identified. Extension of this newly conceived method to other biomass material and potential coupling to other methods of thermal analysis seems feasible in the future. [Copyright &y& Elsevier]

Abstract: PVC and tobacco samples were pyrolyzed in a rotary furnace at different temperatures and reaction gas compositions. Released gaseous products were analyzed using single photon ionization (SPI)/resonance enhanced multiphoton ionization (REMPI)–time-of-flight mass spectrometry (TOFMS). These soft and selective ionization techniques allow fast and comprehensive on-line monitoring of a large variety of aliphatic and aromatic substances without fragmentation of the molecular ions. The thermal decomposition of PVC led to the appearance of chlorinated aromatic compounds at trace levels, which could be detected with SPI–TOFMS. Polycyclic aromatic hydrocarbons (PAH) were simultaneously accessible by REMPI–TOFMS. Different tobacco types can be distinguished by photoionization mass spectrometry of their gaseous pyrolysis products. In addition, pyrolysis products can be classified in three groups depending on their behaviour at different pyrolysis temperatures, which might help to unravel formation mechanisms and chemical pathways of hazardous substances. [Copyright &y& Elsevier]