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Pierre Faure - One of the best experts on this subject based on the ideXlab platform.
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FerrateVI oxidation of polycyclic aromatic compounds (PAHs and polar PACs) on DNAPL-spiked sand: degradation efficiency and oxygenated by-product formation compared to conventional oxidants
Environmental Science and Pollution Research, 2020Co-Authors: Clotilde Johansson, Antoine Joubert, Coralie Biache, Thierry Pigot, Philippe Bataillard, Catherine Lorgeoux, Stéfan Colombano, Pierre FaureAbstract:In situ chemical oxidations are known to remediate PAH contaminations in groundwater and soils. In this study, batch-scale oxidations aim to compare the PAC (polycyclic aromatic compound) degradation of three oxidation processes traditionally applied for soil treatment: permanganate, heat-activated persulfate (60 °C) and Fenton-like activated by magnetite, to results obtained with ferrates (FeVI). Widely studied for water treatments, ferrates are efficient on a wide range of pollutants with the advantage of producing nontoxic ferric sludge after reaction. However, fewer works focus on their action on soil, especially on semi-industrial grade ferrates (compatible with field application). Oxidations were carried out on sand spiked with dense non-aqueous phase liquid (DNAPL) sampled in the groundwater of a former coking plant. Conventional 16 US-EPA PAHs and polar PACs were monitored, especially potential oxygenated by-products that can be more harmful than parent-PAHs. After seven reaction days, only the Fenton-like showed limited degradation. Highest efficiencies were obtained for heat-activated persulfate with no O-PAC ketones formed. Permanganate gave important degradation, but ketones were generated in large amount. The tested ferrates not only gave slightly lower yields due to their auto-decomposition but also induced O-PAC ketone production, suggesting a reactional pathway dominated by oxidoreductive electron transfer, rather than a radical one.
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Ferrate^VI oxidation of polycyclic aromatic compounds (PAHs and polar PACs) on DNAPL-spiked sand: degradation efficiency and oxygenated by-product formation compared to conventional oxidants
Environmental Science and Pollution Research, 2019Co-Authors: Clotilde Johansson, Antoine Joubert, Coralie Biache, Thierry Pigot, Philippe Bataillard, Catherine Lorgeoux, Stéfan Colombano, Pierre FaureAbstract:In situ chemical oxidations are known to remediate PAH contaminations in groundwater and soils. In this study, batch-scale oxidations aim to compare the PAC (polycyclic aromatic compound) degradation of three oxidation processes traditionally applied for soil treatment: permanganate, heat-activated persulfate (60 °C) and Fenton-like activated by magnetite, to results obtained with ferrates (Fe^VI). Widely studied for water treatments, ferrates are efficient on a wide range of pollutants with the advantage of producing nontoxic ferric sludge after reaction. However, fewer works focus on their action on soil, especially on semi-industrial grade ferrates (compatible with field application). Oxidations were carried out on sand spiked with dense non-aqueous phase liquid (DNAPL) sampled in the groundwater of a former coking plant. Conventional 16 US-EPA PAHs and polar PACs were monitored, especially potential oxygenated by-products that can be more harmful than parent-PAHs. After seven reaction days, only the Fenton-like showed limited degradation. Highest efficiencies were obtained for heat-activated persulfate with no O-PAC ketones formed. Permanganate gave important degradation, but ketones were generated in large amount. The tested ferrates not only gave slightly lower yields due to their auto-decomposition but also induced O-PAC ketone production, suggesting a reactional pathway dominated by oxidoreductive electron transfer, rather than a radical one.
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Oxidation of N-hexadecane and crude oil in response to injection of a CO2/O2 mixture under depleted reservoir conditions: Experimental and kinetic modeling preliminary results
International Journal of Greenhouse Gas Control, 2015Co-Authors: Claire Pacini-petitjean, Pierre Faure, Valérie Burkle-vitzthum, Aurélien Randi, Jacques PirononAbstract:CO2 capture and storage in hydrocarbon reservoir seems to be a good solution to reduce greenhouse gas emissions. However, combustion residual gases are not only composed of CO2 but also associated with minor gases. In the case of oxy-combustion, the main minor gas is oxygen in elevated proportion (up to 7%). O-2 injection can induce hydrocarbon oxidations and hence it is necessary to evaluate its consequences on the storage. Hydrocarbon oxidations were studied with a double approach: experiments and kinetic modeling. In a first step, pyrolysis of a model hydrocarbon (n-hexadecane) in CO2 atmosphere reveals no chemical reactivity between hydrocarbons and CO2. Experimental oxidations were then carried out by injecting artificial air in a closed reactor on: (i) a pure n-alkane (n-hexadecane) and (ii) a natural crude oil. Results of both experimental and numerical modeling showed two oxidation types depending on temperature: a low oxidation, and an auto-ignition. The simulation results were globally in agreement with experiments but need to be adapted to low temperature-high pressure conditions. The preliminary findings of this investigation emphasize on the oxidation consequences: (i) on oil composition and (ii) risk (auto-ignition) in context of gas mixture injection (CO2/O-2) in petroleum system.
Jean-luc Parrain - One of the best experts on this subject based on the ideXlab platform.
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trans-1,2-Disiloxybenzocyclobutene, an adequate partner for the Auto-Oxidation: EPR/spin trapping and theoretical studies.
Physical chemistry chemical physics : PCCP, 2014Co-Authors: Jean Drujon, Raphaël Rahmani, Virginie Héran, Romain Blanc, Yannick Carissan, Béatrice Tuccio, Laurent Commeiras, Jean-luc ParrainAbstract:The Auto-Oxidation of trans-1,2-disiloxybenzocyclobutene 1 was found to be very efficient, giving endo-peroxide 7 in quantitative yield. Each step of the mechanism of spin-forbidden addition of triplet oxygen O2(3Σg) was studied by both EPR/spin trapping and theoretical studies.
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Trans-1,2-disiloxybenzocyclobutene, an adequate partner for the auto-oxisation: EPR/spin trapping and theoretical studies
Physical Chemistry Chemical Physics, 2014Co-Authors: Jean Drujon, Raphaël Rahmani, Virginie Héran, Romain Blanc, Yannick Carissan, Béatrice Tuccio, Laurent Commeiras, Jean-luc ParrainAbstract:The Auto-Oxidation of trans-1,2-disiloxybenzocyclobutene was found to be very efficient, giving endoperoxide in quantitative yield. Each step of the mechanism of spin-forbidden addition of triplet oxygen O2 was studied by both EPR/spin trapping and theoretical studies.
Federico Pomar - One of the best experts on this subject based on the ideXlab platform.
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H2O2 generation during the auto‐oxidation of coniferyl alcohol drives the oxidase activity of a highly conserved class III peroxidase involved in lignin biosynthesis
FEBS Letters, 2002Co-Authors: Federico Pomar, Nuria Caballero, María A. Pedreño, A. Ros BarcelóAbstract:Characterization of lignified Zinnia elegans hypocotyls by both alkaline nitrobenzene oxidation and thioacidolysis reveals that coniferyl alcohol units are mainly found as part of 4-O-linked end groups and aryl-glycerol-β-aryl ether (β-O-4) structures. Z. elegans hypocotyls also contain a basic peroxidase (EC 1.11.1.7) capable of oxidizing coniferyl alcohol in the absence of H2O2. Results showed that the oxidase activity of the Z. elegans basic peroxidase is stimulated by superoxide dismutase, and inhibited by catalase and anaerobic conditions. Results also showed that the oxidase activity of this peroxidase is due to an evolutionarily gained optimal adaptation of the enzyme to the μM H2O2 concentrations generated during the Auto-Oxidation of coniferyl alcohol, the stoichiometry of the chemical reaction (mol coniferyl alcohol auto-oxidized/mol H2O2 formed) being 0.496. These results therefore suggest that the H2O2 generated during the Auto-Oxidation of coniferyl alcohol is the main factor that drives the unusual oxidase activity of this highly conserved lignin-synthesizing class III peroxidase.
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H(2)O(2) generation during the Auto-Oxidation of coniferyl alcohol drives the oxidase activity of a highly conserved class III peroxidase involved in lignin biosynthesis.
FEBS letters, 2002Co-Authors: Federico Pomar, Nuria Caballero, María A. Pedreño, A Ros BarcelóAbstract:Characterization of lignified Zinnia elegans hypocotyls by both alkaline nitrobenzene oxidation and thioacidolysis reveals that coniferyl alcohol units are mainly found as part of 4-O-linked end groups and aryl-glycerol-beta-aryl ether (beta-O-4) structures. Z. elegans hypocotyls also contain a basic peroxidase (EC 1.11.1.7) capable of oxidizing coniferyl alcohol in the absence of H(2)O(2). Results showed that the oxidase activity of the Z. elegans basic peroxidase is stimulated by superoxide dismutase, and inhibited by catalase and anaerobic conditions. Results also showed that the oxidase activity of this peroxidase is due to an evolutionarily gained optimal adaptation of the enzyme to the microM H(2)O(2) concentrations generated during the Auto-Oxidation of coniferyl alcohol, the stoichiometry of the chemical reaction (mol coniferyl alcohol auto-oxidized/mol H(2)O(2) formed) being 0.496. These results therefore suggest that the H(2)O(2) generated during the Auto-Oxidation of coniferyl alcohol is the main factor that drives the unusual oxidase activity of this highly conserved lignin-synthesizing class III peroxidase.
Jean Drujon - One of the best experts on this subject based on the ideXlab platform.
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trans-1,2-Disiloxybenzocyclobutene, an adequate partner for the Auto-Oxidation: EPR/spin trapping and theoretical studies.
Physical chemistry chemical physics : PCCP, 2014Co-Authors: Jean Drujon, Raphaël Rahmani, Virginie Héran, Romain Blanc, Yannick Carissan, Béatrice Tuccio, Laurent Commeiras, Jean-luc ParrainAbstract:The Auto-Oxidation of trans-1,2-disiloxybenzocyclobutene 1 was found to be very efficient, giving endo-peroxide 7 in quantitative yield. Each step of the mechanism of spin-forbidden addition of triplet oxygen O2(3Σg) was studied by both EPR/spin trapping and theoretical studies.
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Trans-1,2-disiloxybenzocyclobutene, an adequate partner for the auto-oxisation: EPR/spin trapping and theoretical studies
Physical Chemistry Chemical Physics, 2014Co-Authors: Jean Drujon, Raphaël Rahmani, Virginie Héran, Romain Blanc, Yannick Carissan, Béatrice Tuccio, Laurent Commeiras, Jean-luc ParrainAbstract:The Auto-Oxidation of trans-1,2-disiloxybenzocyclobutene was found to be very efficient, giving endoperoxide in quantitative yield. Each step of the mechanism of spin-forbidden addition of triplet oxygen O2 was studied by both EPR/spin trapping and theoretical studies.
Clotilde Johansson - One of the best experts on this subject based on the ideXlab platform.
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FerrateVI oxidation of polycyclic aromatic compounds (PAHs and polar PACs) on DNAPL-spiked sand: degradation efficiency and oxygenated by-product formation compared to conventional oxidants
Environmental Science and Pollution Research, 2020Co-Authors: Clotilde Johansson, Antoine Joubert, Coralie Biache, Thierry Pigot, Philippe Bataillard, Catherine Lorgeoux, Stéfan Colombano, Pierre FaureAbstract:In situ chemical oxidations are known to remediate PAH contaminations in groundwater and soils. In this study, batch-scale oxidations aim to compare the PAC (polycyclic aromatic compound) degradation of three oxidation processes traditionally applied for soil treatment: permanganate, heat-activated persulfate (60 °C) and Fenton-like activated by magnetite, to results obtained with ferrates (FeVI). Widely studied for water treatments, ferrates are efficient on a wide range of pollutants with the advantage of producing nontoxic ferric sludge after reaction. However, fewer works focus on their action on soil, especially on semi-industrial grade ferrates (compatible with field application). Oxidations were carried out on sand spiked with dense non-aqueous phase liquid (DNAPL) sampled in the groundwater of a former coking plant. Conventional 16 US-EPA PAHs and polar PACs were monitored, especially potential oxygenated by-products that can be more harmful than parent-PAHs. After seven reaction days, only the Fenton-like showed limited degradation. Highest efficiencies were obtained for heat-activated persulfate with no O-PAC ketones formed. Permanganate gave important degradation, but ketones were generated in large amount. The tested ferrates not only gave slightly lower yields due to their auto-decomposition but also induced O-PAC ketone production, suggesting a reactional pathway dominated by oxidoreductive electron transfer, rather than a radical one.
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Ferrate^VI oxidation of polycyclic aromatic compounds (PAHs and polar PACs) on DNAPL-spiked sand: degradation efficiency and oxygenated by-product formation compared to conventional oxidants
Environmental Science and Pollution Research, 2019Co-Authors: Clotilde Johansson, Antoine Joubert, Coralie Biache, Thierry Pigot, Philippe Bataillard, Catherine Lorgeoux, Stéfan Colombano, Pierre FaureAbstract:In situ chemical oxidations are known to remediate PAH contaminations in groundwater and soils. In this study, batch-scale oxidations aim to compare the PAC (polycyclic aromatic compound) degradation of three oxidation processes traditionally applied for soil treatment: permanganate, heat-activated persulfate (60 °C) and Fenton-like activated by magnetite, to results obtained with ferrates (Fe^VI). Widely studied for water treatments, ferrates are efficient on a wide range of pollutants with the advantage of producing nontoxic ferric sludge after reaction. However, fewer works focus on their action on soil, especially on semi-industrial grade ferrates (compatible with field application). Oxidations were carried out on sand spiked with dense non-aqueous phase liquid (DNAPL) sampled in the groundwater of a former coking plant. Conventional 16 US-EPA PAHs and polar PACs were monitored, especially potential oxygenated by-products that can be more harmful than parent-PAHs. After seven reaction days, only the Fenton-like showed limited degradation. Highest efficiencies were obtained for heat-activated persulfate with no O-PAC ketones formed. Permanganate gave important degradation, but ketones were generated in large amount. The tested ferrates not only gave slightly lower yields due to their auto-decomposition but also induced O-PAC ketone production, suggesting a reactional pathway dominated by oxidoreductive electron transfer, rather than a radical one.
