l'HPLC ionique
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l'HPLC ionique

  1. #1

    l'HPLC ionique


    voilà je recherche des applications industrielle de l'hplc ionique j'ai chercher sur le net mais je ne trouve vraiment rien


  2. #2

    Re : l'HPLC ionique

    En haute pression il n'y a probablement que tres peu d'application car les phase échangeuses d'ions sont semsibles aux fortes pressions et les débits ne doivent pas êtres trop rapides, mais en basse pression il y en a.

    Autrefois l'on séparait les lanthanides (usine (Rhone poulec?) à La Rochelle) mais maintenant on utilise l'extraction liquide liquide.

    Il faut aussi regarder les chromatographies continues type SMB (moving bed simulated (lit mobile simulé)) ou varicol, ces procedés sont souvent utilisés pour des séparation chirales, mais peuvent être employé pour d'autres séparations ou l'on sépare les solutés en deux groupes.

    Il est probable qu'il y ait des application de separation sur les sucres, il y en a sur des produit pharmaceutique mais c'est souvent confidentiel .

    ce lien
    Application to the Production of Industrial Sugars

    La phase est echangeuse d'ion mais est-ce vraiment une chromatographie ionique?


    ce lien

    j'ai recopié une grande partie
    Application to the Production of Industrial Sugars
    The present work comprises theoretical and experimental aspects of the continuous chromatographic process of simulated moving bed (SMB), used either as an adsorber or as a chemical reactor. The main practical application concerns the production of industrial sugars, such as glucose, fructose and sucrose. Generally speaking, SMB chromatography allows continuous injection and separation (with or without reaction) of binary mixtures. When a chemical reaction and simultaneous separation occur, the equipment is named a simulated moving bed reactor (SMBR). In both cases, a countercurrent contact between fluid and solid (adsorbent and/or catalyst) phases is simulated, which maximises the driving force for mass transfer and/or promotes a shift in chemical reaction equilibrium favouring higher conversions.In regards to the modeling of the separation of sugar mixtures by SMB, two approaches were followed: that of a true moving bed (TMB) and that of an actual simulated moving bed (SMB). In the first approach, we have proposed a more sophisticated description of intraparticle mass transfer. In the SMB approach, the classical LDF approximation was used. Both approaches provide identical results, as long as the proper relations of equivalence are applied. A methodology of prediction of adequate SMB operating conditions was presented by means of the analysis of ?Separation Volume?. This analysis makes it possible to address the effects of fluid-solid velocity ratios in regeneration sections 1 and 4, which is an often overlooked aspect by most authors.As for the simulated moving bed reactor, detailed process models were described based on the strategies previously mentioned. A design algorithm was proposed in order to size SMBR units for the case of sucrose inversion and separation of products fructose and glucose. The algorithm results were used for optimization purposes by defining the sucrose/enzyme ratio (catalyst productivity) as the objective function. The optimal operating points, in terms of the velocity ratios in sections 2 and 3, followed an interesting behaviour,which was quite different from that expected for a non-reactive SMB in the frame of the equilibrium theory.Experimental data for the SMB as a separator (fructose-glucose mixtures) and as a reactor-separator (inversion of sucrose) were obtained in a pilot unit Licosep 12-26 (Novasep, France), available at LSRE. Twelve columns were packed with cationic resin DOWEX Monosphere 99/Ca (Sigma) with a particle size of 320 µm. Experimental data obtained for both systems were reasonably well predicted by the respective process models. SMBR data confirmed the occurrence of enzyme immobilisation by the adsorbent, which may enhancesavings in the amount of enzyme required by the reactor.Finally, experimental results are shown for the separation of fructose and glucose fromcashew (Anacardium occidentale, L.) apple juice, an abundant and sub-utilised crop in Northeastern Brazil. HPLC analysis revealed the presence of fructose and glucose in nearly equal amounts. Successful separation of fructose and glucose was achieved by SMB using filtered cashew apple juice as feed. SMB performance at steady state, as well as stationary concentration profiles of both sugars, were well simulated by the described process models.

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