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Selective homogeneous oxidation system for producing hydroperoxides concentrate / Syed Mumtaz Danish Naqvi in Industrial & engineering chemistry research, Vol. 49 N° 16 (Août 2010) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7210–7226 Titre : Selective homogeneous oxidation system for producing hydroperoxides concentrate : kinetic simulation of catalytic oxidation of gas oils Type de document : texte imprimé Auteurs : Syed Mumtaz Danish Naqvi, Auteur ; Muhammad Ashraf Kamal, Auteur ; Fasihullah Khan, Auteur Année de publication : 2010 Article en page(s) : pp. 7210–7226 Note générale : Industrial chemistry Langues : Anglais (eng) Mots-clés : Modeling  Gas  oil  Catalytic  reaction  Catalytic  reaction  Oxidation Résumé : Homogeneous production of hydroperoxides concentrate has been simulated via multivariate calibration of yield data, obtained during an earlier study [Naqvi and Khan Ind. Eng. Chem. Res. 2009, 48, 5642] made on the air oxidation of diluted gas oils in the presence of chemically generated redox couple Co(III)/Co(II). Principal component analysis has been applied to abstract dynamic hydroperoxides yield data that provides the basis for the simulation. A novel chemometric technique, inverse nonlinear principal component regression, has been introduced to simulate experimental yield profiles with exceptional accuracy (R2 = 0.9841). Simulated yield profiles have then been subjected to Levenberg−Marquardt method in order to estimate the rate constants for formation and decomposition of hydroperoxides. These estimations have permitted the development of two reasonably accurate multivariate global models that relate the specific rates, for formation (R2 = 0.8873) and decomposition (R2 = 0.9504) of hydroperoxides, to process and composition variables. Construction of such models allows the specific rates to be optimized so that the reactor could be operated at an oil conversion (up to ≈5%) that is almost proportional to the yield of hydroperoxides ensuring selectivity ≈88%. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100327m [article] Selective homogeneous oxidation system for producing hydroperoxides concentrate : kinetic simulation of catalytic oxidation of gas oils [texte imprimé] / Syed Mumtaz Danish Naqvi, Auteur ; Muhammad Ashraf Kamal, Auteur ; Fasihullah Khan, Auteur . - 2010 . - pp. 7210–7226. Industrial chemistry Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 49 N° 16 (Août 2010) . - pp. 7210–7226 Mots-clés : Modeling  Gas  oil  Catalytic  reaction  Catalytic  reaction  Oxidation Résumé : Homogeneous production of hydroperoxides concentrate has been simulated via multivariate calibration of yield data, obtained during an earlier study [Naqvi and Khan Ind. Eng. Chem. Res. 2009, 48, 5642] made on the air oxidation of diluted gas oils in the presence of chemically generated redox couple Co(III)/Co(II). Principal component analysis has been applied to abstract dynamic hydroperoxides yield data that provides the basis for the simulation. A novel chemometric technique, inverse nonlinear principal component regression, has been introduced to simulate experimental yield profiles with exceptional accuracy (R2 = 0.9841). Simulated yield profiles have then been subjected to Levenberg−Marquardt method in order to estimate the rate constants for formation and decomposition of hydroperoxides. These estimations have permitted the development of two reasonably accurate multivariate global models that relate the specific rates, for formation (R2 = 0.8873) and decomposition (R2 = 0.9504) of hydroperoxides, to process and composition variables. Construction of such models allows the specific rates to be optimized so that the reactor could be operated at an oil conversion (up to ≈5%) that is almost proportional to the yield of hydroperoxides ensuring selectivity ≈88%. ISSN : 0888-5885 En ligne : http://pubs.acs.org/doi/abs/10.1021/ie100327m

Selective homogeneous oxidation system for producing hydroperoxides concentrate / Syed Mumtaz Danish Naqvi in Industrial & engineering chemistry research, Vol. 48 N° 12 (Juin 2009) 

Public ISBD [article]  in Industrial & engineering chemistry research > Vol. 48 N° 12 (Juin 2009) . - pp. 5642–5655 Titre : Selective homogeneous oxidation system for producing hydroperoxides concentrate : kinetics of catalytic oxidation of gas oils Type de document : texte imprimé Auteurs : Syed Mumtaz Danish Naqvi, Auteur ; Fasihullah Khan, Auteur Année de publication : 2009 Article en page(s) : pp. 5642–5655 Note générale : Chemical engineering Langues : Anglais (eng) Mots-clés : Selective  homogeneous  oxidation  system  Hydroperoxides  Gas  oil Résumé : A selective and mild (55 °C and 50 psig) homogeneous oxidation system has been described to produce hydroperoxides from a narrow cut made from typical gas oil. During this process oil, dissolved in wet acetic acid, is treated with air in the presence of the redox couple Co(III)/Co(II) (partially oxidized catalyst, POC). A straightforward route to POC consists of oxidizing Co(II) in wet acetic acid with calculated aqueous potassium chlorate. Initiation is the manifestation of the potent oxidizing ability of Co(III) toward generating alkyl radicals from hydrocarbons in the oil. Classical propagation then leads to assorted hydroperoxides, simultaneously decomposed by POC. Kinetics of the simultaneous formation and decomposition of hydroperoxides, under varying sets of process and composition variables, was studied in an isothermal, mechanically agitated, semibatch reactor, operating in the pure kinetic regime. A unique kinetic model, based on a rare irreversible consecutive reaction network (pseudo-first-order formation of hydroperoxides followed by their second-order decomposition), has been found to reasonably describe the kinetic data (R2 = 0.9214). This kinetic model allowed the evaluation of the formation and decomposition rate constants that permitted the estimation of conversion of oil and selectivity to hydroperoxides. On average 15.12 ± 3.23% conversion was achieved in 9.3 ± 4.0 min with 99.86 ± 0.23, 92.88 ± 7.95, and 28.77 ± 11.67% selectivities for 0.10, 1.00, and 10.0% conversions, respectively. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900364w [article] Selective homogeneous oxidation system for producing hydroperoxides concentrate : kinetics of catalytic oxidation of gas oils [texte imprimé] / Syed Mumtaz Danish Naqvi, Auteur ; Fasihullah Khan, Auteur . - 2009 . - pp. 5642–5655. Chemical engineering Langues : Anglais (eng) in Industrial & engineering chemistry research > Vol. 48 N° 12 (Juin 2009) . - pp. 5642–5655 Mots-clés : Selective  homogeneous  oxidation  system  Hydroperoxides  Gas  oil Résumé : A selective and mild (55 °C and 50 psig) homogeneous oxidation system has been described to produce hydroperoxides from a narrow cut made from typical gas oil. During this process oil, dissolved in wet acetic acid, is treated with air in the presence of the redox couple Co(III)/Co(II) (partially oxidized catalyst, POC). A straightforward route to POC consists of oxidizing Co(II) in wet acetic acid with calculated aqueous potassium chlorate. Initiation is the manifestation of the potent oxidizing ability of Co(III) toward generating alkyl radicals from hydrocarbons in the oil. Classical propagation then leads to assorted hydroperoxides, simultaneously decomposed by POC. Kinetics of the simultaneous formation and decomposition of hydroperoxides, under varying sets of process and composition variables, was studied in an isothermal, mechanically agitated, semibatch reactor, operating in the pure kinetic regime. A unique kinetic model, based on a rare irreversible consecutive reaction network (pseudo-first-order formation of hydroperoxides followed by their second-order decomposition), has been found to reasonably describe the kinetic data (R2 = 0.9214). This kinetic model allowed the evaluation of the formation and decomposition rate constants that permitted the estimation of conversion of oil and selectivity to hydroperoxides. On average 15.12 ± 3.23% conversion was achieved in 9.3 ± 4.0 min with 99.86 ± 0.23, 92.88 ± 7.95, and 28.77 ± 11.67% selectivities for 0.10, 1.00, and 10.0% conversions, respectively. En ligne : http://pubs.acs.org/doi/abs/10.1021/ie900364w