Membrane bioreactor for lactic acid production

Moueddeb, Hichem; Sánchez, J.; Bardot, C.; Fick, Michel

doi:10.1016/0376-7388(95)00307-x

Cited by 34 publications

(11 citation statements)

References 11 publications

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“…This separation can be carried out either in batch at the end of the fermentation process or continuously by recirculating the biomass through a filtration unit connected to the fermentor. The advantage of a continuous extraction process is the possibility of reaching higher cellular concentration which increases the efficiency as observed by Tong et al (1998) and Moueddeb et al (1996) for the production of lactic acid. Moreover, because the product is continuously withdrawn, its concentration is maintained at a low value which avoids the metabolism limitation by the product.…”

Section: Biopolymer Recovery By Membranementioning

confidence: 99%

Influence of fermentation conditions and microfiltration processes on membrane fouling during recovery of glucuronane polysaccharides from fermentation broths

Harscoat¹,

Jaffrin²,

Bouzerar³

et al. 1999

Biotechnol. Bioeng.

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We have investigated the recovery of exopolysaccharides produced by Sinorhizobium meliloti M5N1 CS bacteria from fermentation broths using different membrane filtration processes: cross-flow filtration with a 7 mm i.d. tubular ceramic membrane of 0.5-microm pores under fixed transmembrane pressure or fixed permeate flux and dynamic filtration with a 0.2 microm nylon membrane using a 16-cm rotating disc filter. With the tubular membrane, the polysaccharide mass flux was mainly limited by polymer transmission that decayed to 10% after 90 min. The mass flux of polymer produced under standard fermentation conditions (70 h at 30 degrees C) stabilized after 70 min to 15 g/h/m(2). This mass flux rises to 36 g/h/m(2) when the mean stirring speed during fermentation is increased and to 123 g/h/m(2) when fermentation is extended to 120 h. In both cases, the mean molecular weight of polysaccharides drops from 4.0 10(5) g/mol under standard conditions to 2.7 10(5) g/mol. A similar reduction in molecular weight was observed when the fermentation temperature was raised to 36 degrees C without benefit to the mass flux. These changes in fermentation conditions have little effect on stabilized permeate flux, but raise significantly the sieving coefficient, due probably to molecular weight reduction and the filamentous aspect of the polymer as observed from SEM photographs. The polymer-mass flux was also increased by reducing transmembrane pressure (TMP) and raising the shear rate by inserting a rod in the membrane lumen. Operation under fixed permeate flux instead of constant TMP inhibited fouling during the first 4 h, resulting in higher sieving coefficients and polymer mass fluxes. The most interesting results were obtained with dynamic filtration because it allows operation at high-shear rates and low TMP. Sieving coefficients remained between 90 and 100%. With a smooth disc, the polysaccharide mass flux remained close to 180 g/h/m(2) at 1500 rpm and cell concentrations from 1 to 3 g/L. When radial rods were glued to the disc to increase wall shear stress and turbulence, the mass flux rose to 275 g/h/m(2) at the same speed and cell concentration.

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Section: Biopolymer Recovery By Membranementioning

confidence: 99%

Influence of fermentation conditions and microfiltration processes on membrane fouling during recovery of glucuronane polysaccharides from fermentation broths

Harscoat¹,

Jaffrin²,

Bouzerar³

et al. 1999

Biotechnol. Bioeng.

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“…Recently, nanoporous alumina membranes were also employed in non-filtrationrelated applications including templates for synthesis of nanowires, 4,5 nanorods 6 and as support for cell cultures. 7 However, these applications employ alumina membranes without further surface treatment. Surface modification of the alumina membranes could produce surfaces with varied hydrophobic properties and functionalities and, therefore, potentially extend the use of alumina membranes beyond its current application range.…”

Section: Introductionmentioning

confidence: 99%

Grafting of nanoporous alumina membranes and films with organic acids

Cheow

Liu

Toh

2007

Surface & Interface Analysis

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In this study, direct surface grafting of nanoporous alumina membranes and glass-supported alumina films was carried out with three different fluorinated organic acids: trifluoroacetic acid, perfluoropentanoic acid and 2,3,4,5,6-pentafluorobenzoic acid. Elemental surface composition and chemical environment of alumina were investigated using X-ray photoelectron spectroscopy (XPS) and Fourier transform infrared spectroscopy (FTIR). Alumina surfaces grafted with fluoro-organic acids exhibited increased hydrophobic properties compared to ungrafted surfaces when measured using goniometry and atomic force microscopy (AFM). This work describes the evidence for surface chemical modification of alumina using direct reaction with organic acids. An AFM study of the adsorption of the immunoglobulin G (IgG) molecules on the fluoro-organic-acid-grafted surfaces is reported. The results show that an ordered arrangement of immunoglobulin G structures with in-filling of pores could be achieved only on the more hydrophobic fluoro-organic-acid-grafted alumina membranes.

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“…A number of processes for lactic acid recovery from fermentation broth without precipitation have been studied: solvent extraction,8–15 membrane bioreactor,16, 17 liquid surfactant membrane extraction,18, 19 adsorption,20 direct distillation,21 electrodialysis,22–24 chromatographic methods,15 ultrafiltration,15 reverse osmosis,15, 25 drying,15 etc.…”

Section: Introductionmentioning

confidence: 99%

Equilibria and kinetics for reactive extraction of lactic acid using Alamine 336 in decanol

Wasewar

Heesink

Versteeg

et al. 2002

J of Chemical Tech & Biotech

114

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Lactic acid is an important commercial product and extracting this from aqueous solution is a growing requirement in fermentation-based industries. The design of an amine extraction process requires (i) equilibrium and (ii) kinetic data for the acid±amine (solvent) system used. The equilibrium complexation constants for ratios of (1:1) and (2:1) have been estimated. The kinetics of extraction of lactic acid by Alamine 336 in decanol has also been determined. The reaction between lactic acid and Alamine 336 in decanol in a stirred cell falls in Regime 3, ie extraction accompanied by a fast chemical reaction occurring in the diffusion ®lm. The reaction has been found to be zero order in Alamine 336 and ®rst order in lactic acid with a rate constant of 0.21 s À1. These data will be useful in the design of extraction processes.

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Membrane bioreactor for lactic acid production

Cited by 34 publications

References 11 publications

Influence of fermentation conditions and microfiltration processes on membrane fouling during recovery of glucuronane polysaccharides from fermentation broths

Influence of fermentation conditions and microfiltration processes on membrane fouling during recovery of glucuronane polysaccharides from fermentation broths

Grafting of nanoporous alumina membranes and films with organic acids

Equilibria and kinetics for reactive extraction of lactic acid using Alamine 336 in decanol

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