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Elgue S.,Safran | Conte A.,Safran | Gourdon C.,Laboratoire Of Genie Chimique | Bastard Y.,Axyntis Group
Chimica Oggi/Chemistry Today | Year: 2012

Direct fluorination of an Axyntis® 1,3-dicarbonyl compound is investigated at industrial scale in a commercial continuous flow reactor under gas-liquid conditions. The considered flow reactor manufactured by Boostec®, is made of silicon carbide that offers relevant heat transfer performances with regards to reaction exothermicity, as well as corrosion resistance. A screening of the operating conditions and more precisely on solvent and on catalyst was performed to demonstrate the feasibility of the reaction in a continuous mode. To work in a safe and non-hazardous environment regarding the reaction characteristics, experiments have been carried out at the MEPI facility (Maison Européenne des Procédés Innovants). The results show that in slug flow regime full conversion could be achieved with few seconds residence time while reaching a productivity level about 200 g per hour.

Filali A.,Toulouse 1 University Capitole | Manas A.,Toulouse 1 University Capitole | Mercade M.,Toulouse 1 University Capitole | Bessiere Y.,Toulouse 1 University Capitole | And 2 more authors.
Biochemical Engineering Journal | Year: 2012

Two granular sludge sequencing batch reactors (GSBR) with alternating anoxic/aerobic (R1) and anaerobic/aerobic (R2) conditions were operated with a 4-carbon-source synthetic influent. The physical properties of the granular sludge were very good (SVI≈20mLg -1) and high solid concentrations (up to 35gL -1) were obtained in the bioreactor operated with a pre-anoxic phase with additional nitrate (R1). In contrast, performance and granule settleability were lower in R2 due to the development of filamentous heterotrophic bacteria on the surface of granules. These disturbances were linked to the fact that a fraction of COD remained during the aerobic phase, which was not stored during the anaerobic period. To stabilize a GSBR with a mixture of organic carbon sources, it is thus necessary to maximize the amount of substrate used during the non-aerated, anaerobic or anoxic, phase. Comparable phosphate removal efficiency was observed in both systems; enhanced biological P removal being greater in anaerobic/aerobic conditions, while the contribution of precipitation (Ca-P) was more significant in anoxic/aerobic conditions. © 2012 Elsevier B.V.

Haddou B.,Oran University of Science and Technology - Mohamed Boudiaf | Guitri N.,Oran University of Science and Technology - Mohamed Boudiaf | Debbab A.,Oran University of Science and Technology - Mohamed Boudiaf | Gourdon C.,Laboratoire Of Genie Chimique | Derriche Z.,Oran University of Science and Technology - Mohamed Boudiaf
Separation Science and Technology | Year: 2011

The aim of this work was to compare two synthetic dyes, Orange G (7-Hydroxy-8-(phenylazo)-1,3-naphthalenedisulfonic acid, disodium salt) and Orange II (p-(2-Hydroxy-1-naphthylazo) benzenesulfonic acid, sodium salt), towards cloud point extraction from colored water. Three commercial non-ionic surfactants were used in this work: Oxo-C15E7, Oxo-C10E3, and Triton X-100. The experimental extraction results were expressed by the following three responses: percentage of the extracted dye (E), residual concentrations of dye in the dilute phase (Xs,w), and the volume fraction of coacervate (φC) at the equilibrium. The results obtained for each parameter were represented on three dimensional diagrams using an empirical smoothing method. In optimal conditions Orange II concentration in the effluent was reduced to about 227 times, whereas E did not exceed 55% using Oxo-C15E7 in the case of Orange G extraction. However, when a small amount (0.025 wt.%) of cetyltrimethylammonium bromide (CTAB) was combined with Oxo-C10E3 as a mixed micelles system, the results showed that the extraction percentage of Orange G increased from 55 to 98%. Indeed, the concentration of this dye in the effluent was reduced to about 400 times. Finally, the extraction extent of both dyes was found to be low at basic pH, which may be useful for surfactant regeneration. © Taylor & Francis Group, LLC.

Comtat M.,Laboratoire Of Genie Chimique
Actualite Chimique | Year: 2015

With Henri Pitot, Paulin Talabot, Henri Merle and Paul Rivals are evocated some mutations of the society in Provence, the beginning of industrialisation, the history of soap and aluminium and the construction of the Faculty of Sciences in Marseille.

Rebai M.,National Polytechnic Institute of Toulouse | Rebai M.,French National Center for Scientific Research | Prat M.,National Polytechnic Institute of Toulouse | Prat M.,French National Center for Scientific Research | And 5 more authors.
Chemical Engineering Science | Year: 2010

A semi-analytical model of gas flow in pleated fibrous filters is developed for large filtration velocities. This case presents two main new and distinguishing features compared to the low filtration velocity situations studied in previous works: the velocity profiles are not parabolic within the pleat channels and the filtration velocity is not uniform along the pleated filter element and this has a great impact on the filter loading. The model relies on similarity solutions to the Navier-Stokes equations in the channels formed by pleating the filter medium. After validation by comparison with direct CFD simulations and experimental data, the model is used to determine the optimal pleat density, i.e. the pleat density minimizing the overall pressure drop across the filter for given flow rate, pleat length and given filter medium properties. As illustrated in the paper, this model greatly facilitates the study of flow within the pleated filter compared to a standard CFD approach. It represents an excellent basis for the more involved problem of filter loading computation. In particular, no remeshing across the width of the pleated filter entrance channels is needed when a filtration cake forms at the channel walls. © 2010 Elsevier Ltd. All rights reserved.

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