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International audience ; Originally developed for high-tech applications in the aeronautic and aerospace industry, carbon/epoxy composites have been increasingly used in the automotive, leisure, and sports industries for several years. Nevertheless, the carbon reinforcement is an expensive constituent, and it has been recently shown that it is also the most environmentally impacting in a composite part manufacturing. Recycling these materials (even restricted to the reinforcement recovery) could lead to economic and environmental benefits, while satisfying legislative end-of-life requirements. The solvolysis of the matrix by water under supercritical conditions is an efficient solution to recover the carbon fiber reinforcement with mechanical properties closed to the ones of virgin fibers. This paper aims at demonstrating the environmental feasibility of the recycling of carbon fiber/thermoset matrix composites by solvolysis of the matrix in supercritical water. This demonstration is based on life cycle assessment that evaluates benefits and environmental challenges of this recycling loop.

International audience ; Originally developed for high-tech applications in the aeronautic and aerospace industry, carbon/epoxy composites have been increasingly used in the automotive, leisure, and sports industries for several years. Nevertheless, the carbon reinforcement is an expensive constituent, and it has been recently shown that it is also the most environmentally impacting in a composite part manufacturing. Recycling these materials (even restricted to the reinforcement recovery) could lead to economic and environmental benefits, while satisfying legislative end-of-life requirements. The solvolysis of the matrix by water under supercritical conditions is an efficient solution to recover the carbon fiber reinforcement with mechanical properties closed to the ones of virgin fibers. This paper aims at demonstrating the environmental feasibility of the recycling of carbon fiber/thermoset matrix composites by solvolysis of the matrix in supercritical water. This demonstration is based on life cycle assessment that evaluates benefits and environmental challenges of this recycling loop.

| openaire: EC/H2020/101006744/EU//EHLCATHOL This work has received funding from the European Union's Horizon 2020 research and innovation program, (BUILDING A LOW-CARBON, CLIMATE RESILIENT FUTURE: SECURE, CLEAN AND EFFICIENT ENERGY) under Grant Agreement No 101006744. The content presented in this document represents the views of the authors, and the European Commission has no liability in respect of the content. This work was also supported by the National Natural Science Foundation of China (21808163 and 21690083). ; A Mo(OCH2CH3)x/NaCl catalyst showed high efficiency in supercritical ethanol without adding H2 in the conversion of Kraft lignin to chemicals, including C6 alcohols, C8-C10 esters, benzyl alcohols and arenes. Control experiments were done with MoCl5, NaOC2H5 and the physical mixture of them. The Mo(OCH2CH3)x/NaCl catalyst exhibited superior activity among the samples examined. The overall yield increased as the reaction temperature increased from 260 to 300 °C. The yield of aromatic compounds achieved 303mg/g lignin over the Mo(OCH2CH3)x/NaCl catalyst at 300oC for 6h. MoCl5 and NaOC2H5 forms Mo(OCH2CH3)x in the catalyst preparation, which behaves as the active species in Kraft lignin conversion. The primary aromatics formed from the catalytic lignin depolymerization steps may undergo secondary reactions to form the final products. ; Peer reviewed

The authors would like to express their thanks to the stakeholders of the RECCO Project. ; International audience ; Originally developed for high-tech applications, carbon/epoxy composites have been increasingly used in leisure and sports industries, for several years. Nevertheless, the carbon reinforcement is an expensive constituent, and it has been recently shown that it is also the most environmentally impacting in a composite part manufacturing. In this way, recycling these materials (even restricted to the reinforcement recovery) could lead to reduce economic and environmental inadequacies, while satisfying legislative requirements for their end-of-life. This article is the basis for a life cycle analysis that assesses benefits and environmental challenges of this recycling loop. The recovery of the carbon reinforcement (based on the solvolysis of the matrix by water under supercritical conditions) offers an average gain of 70% for all eco- indicators.

The authors would like to express their thanks to the stakeholders of the RECCO Project. ; International audience ; Originally developed for high-tech applications, carbon/epoxy composites have been increasingly used in leisure and sports industries, for several years. Nevertheless, the carbon reinforcement is an expensive constituent, and it has been recently shown that it is also the most environmentally impacting in a composite part manufacturing. In this way, recycling these materials (even restricted to the reinforcement recovery) could lead to reduce economic and environmental inadequacies, while satisfying legislative requirements for their end-of-life. This article is the basis for a life cycle analysis that assesses benefits and environmental challenges of this recycling loop. The recovery of the carbon reinforcement (based on the solvolysis of the matrix by water under supercritical conditions) offers an average gain of 70% for all eco- indicators.

The Arrhénius parameters of solvolysis reactions and Sn2 exchange of trans cinnamyl-and β-phenylpropargyl chlorides have been measured.
An approximately equal transmission of polar effects through the C-C double and triple bonds has been observed when the mechanism is Sn2.
On the contrary, for an SN1 mechanism, this transmission is much more important for a C-C double bond than for a triple bond.

A series of azomethines derivated from the α-phenylimino-benzoyl-acetanilide (PIBA) of general formula, PIBAZ : [formula] with [formula], was submitted to acidic solvolysis.
Experimental results of a kinetic study, in an alcohol-water solvent, led to develop a reaction scheme of two nucleophilic additions simultaneously occuring at the protonated azomethinic bond : [formula]
the first one (I) giving an amino-ether (ki) which can only reverse to the original reactants (k-1) and the second one (II) generating an amino-alcohol(kII) which rapidly decomposes into the final products (P) : α, β-dioxo-dihydrocinnamanilide (C6H5— CO— CO— CO— NH— C6H5) and the corresponding aniline (Z— C6H4— HN2). This process undergoes general acid-base catalysis.

This paper appears here with the permission of the publisher. The definitive published version is available at http://www.imanagerpublications.com/Article.aspx?ArticleId=8129&issueid=0 ; This paper presents an assessment of the growing use of Glass Fibre Reinforced Plastic and Carbon Fibre Reinforced Plastic composites in the automotive and marine industry through the decades to current use. This report investigates how legislation such as the End of Life of Vehicles (ELV) will force the automotive industry to prepare for end of life recycling and gauge their progress with the aid of reports from the Knowledge Transfer Network (KTN) and Stella Job, who is Supply Chain and Environment Officer for the UK trade association Composites UK, outlining the process of pyrolysis and solvolysis, with the aid of informal industry interviews and a case study at a small British sports car manufacturer to consider the practical work required.

A systematic study by complementary techniques shows that PET-waste from plastic vessels is a competitive precursor of carbon electrodes for supercapacitors. PET derived-activated carbons follow the general trends observed for highly porous carbons and display specific capacitances at low current density as high as 197 F g−1 in 2 M H2SO4 aqueous electrolyte and 98 F g−1 in the aprotic medium 1 M (C2H5)4NBF4/acetonitrile. Additionally, high performance has also been achieved at high current densities, which confirms the potential of this type of materials for electrical energy storage. A new method based on the basic solvolysis of PET-waste and the subsequent carbonization seems to be an interesting alternative to obtain porous carbons with enhanced properties for supercapacitors. ; The support of the autonomous regional government (J. de Andalucía, P. de Excelencia P06-FQM-01585) is acknowledged. ; Peer reviewed