Membrane reactors Fermentation

Matsumae H, Furui M, Shibatani T, Tosa T (1994), Production of optically active 3-phenylglycidic acid ester by the lipase from Serratia marcescens on a hollow-fiber membrane reactor ,/. Ferment. Bioeng., 78,59-63. 

Cephalosporin is determined from the proton concentration generated in a medium by using immobilized bacteria. A microbial sensor composed of a bacteria-collagen membrane reactor and a combined glass electrode was applied to the determination of cephalosporins in fermentation media. The system used for continuous determination... 

Membrane reactors became an option for the retention of biocatalysts when the processing of membrane materials had progressed sufficiently to control thickness and pore structure and to manufacture a membrane that was defect-free. Besides its function as a retainer the membrane also serves other functions such as (i) to stabilize the phase boundary in case of multi-phase reactions (ii) as a consequence of (i), to transport dissolved 02 preferentially over gaseous 02 and (iii) to support purification and sterilization of air and other nutrients in fermentations. 

Figure 13.18 Continuous recycle fermentor membrane reactor. An ultrafiltration module removes the liquid products of fermentation as a clean product. This system is being developed for production of ethanol, acetone and butanol by fermentation of food processing waste streams...

In a multiphase membrane reactor, the conversion of benzylpenicillin to 6-aminopenidllinic acid is performed. The type of microstructured reactor used is a fermentation reactor which contains the enzyme penicillin acylase immobilized on the wall of a hollow-fiber tube. The hollow-fiber tube extracts 6-aminopenicillinic acid at the same time selectively. Benzylpenicillin is converted at the outer wall of the hollow fiber into the desired product, which passes into the sweep stream inside the fiber where it can be purified, e.g. by ion exchange. The non-converted benzylpenicillin is recycled back through the reactor [84],... 

Drioli, E. and Iorio, G. (1989) Enzyme membrane reactor and membrane fermentators, Handbook of industrial membrane technology (ed. C.P. Mark), Noyes Publications, Park Ridge, New Jersey, USA, pp. 401-481. 

Fermentation is typically conducted in dilute suspension culture. The low concentration in such systems limits reaction efficiency, and the presence of particulate and colloidal solids poses problems for product recovery and purification. By circulating the fermentation broth through an ultrafiltration system, it is possible to recover product continuously as they are generated while minimizing loss of enzyme or cells and keeping product concentration in the bioreactor below the self-inhibition level for the biocatalyst. This process is referred to as perfusion. As the ultrafiltration unit is part of the production process, the entire system is often considered a membrane reactor. 

Processes for production of ethanol and acetone-butanol-ethanol mixture from fermentation products in membrane contactor devices were presented in Refs. [88,89]. Recovery of butanol from fermentation was reported in Ref. [90]. Use of composite membrane in a membrane reactor to separate and recover valuable biotechnology products was discussed in Refs. [91,92]. A case study on using membrane contactor modules to extract small molecular weight compounds of interest to pharmaceutical industry was shown in Ref. [93]. Extraction of protein and separation of racemic protein mixtures were discussed in Refs. [94,95]. Extractions of ethanol and lactic acid by membrane solvent extraction are reported in Refs. [96,97]. A membrane-based solvent extraction and stripping process was discussed in Ref. [98] for recovery of Phenylalanine. Extraction of aroma compounds from aqueous feed solutions into sunflower oil was investigated in Ref. [99]. 

Kamoshita Y, Ohashi R, and Suuzuki T. Improvement of filtration performance of stirred ceramic membrane reactor and its application to rapid fermentation of lactic acid by dense cell culture of Lactoccus lactis. J. Ferment. Bioeng. 1998 85(4) 422 27. 

Plant cells or tissues may be fermented like micro-organisms in the submerged fermenter if grown on the surface of carrier beads or are kept in suspension. There is also experience in the operation of special membrane reactors for this purpose [13]. 

There are many different approaches for in situ ethanol removal during fermentation. These approaches include vacuum distillation, solvent extraction, membrane reactors, and gas stripping (see 114] for review). Gas stripping of ethanol during fermentation offers advantages in terms of its effectiveness and ease of operation [15]. Ethanol can be recovered from the carrier gas stream by adsorbing onto activated carbon [16] or by condensation of the recycled gas stream under low temperatures [17]. 

There is no commonly accepted definition of a membrane reactor but the term is applied to membrane (including liquid membrane) processes and devices whose function is to perform chemical conversion, coupling and combining chemical and transport processes, using the unique contacting features of membranes. As a rule, functional definition of this term includes fermentation, catalysis, separation of the products and their enrichment. A few published reviews at this time are available [98-104]. In most of pubhcations the bioreactors, based on enzymes or whole cells, impregnated into the membrane pores (immobihzed or supported hquid membranes) or deposited on the membrane surfaces are discussed. 

The potential of membrane separation techniques (such as cross-flow microfiltration(MF), ultrafiltration (UF), Reverse Osmosis (RO)and electrodialysis (ED) ) and membrane reactors in the treatment of fermentation broths are huge. The synergistic effects obtainable by designing the overall biotechnological process combining various membrane technique are particularly significant. 

Membrane reactors, whether batch or continuous, offer the possibility of selective transpiration. They can be operated in the reverse mode so that some products are selectively removed from the reaction mixture in order to avoid an equilibrium limitation. Membrane reactors can be used to separate cell mass from fermentation products. See Section 12.2.2. 

Chapter 3 is devoted to the topic of pervaporation membrane reactors. These are unique systems in that they use a liquid feed and a vacuum on the permeate side they also mostly utilize polymeric membranes. Chapter 4 presents a survey of membrane bioreactor processes these couple a biological reactor with a membrane process. Reactions studied in such systems include the broad class of fermentation-type or enzymatic processes, widely used in the biotechnology industry for the production of amino acids, antibiotics, and other fine chemicals. Similar membrane bioreactor systems are also fin-... 

Vaillant, H. and Formisyn, P. (1996) Purification of the malolactic enzyme from a Leuconostoc oenos strain and use in a membrane reactor for achieving the malolactic fermentation of wine. Biotechnol Appl. Biochem., 24, 217-223. 

First applications of membrane reactors can be foimd in the field of bioprocess engineering using whole cells in fermentations or enzymatic bioconversions [6, 7]. Most of these processes use polymeric membranes, as temperatures seldomly exceed 60 °C. The development of inorganic membrane materials (zeolites, ceramics and metals) has broadened the application potential of membrane reactors towards the (petro) chemical industry [8]. Many of these materials can be applied at elevated temperatures (up to 1000°C), allowing their application in catalytic processes. 

The organic phase may also be used as a substrate reservoir, besides their use for product stripping from the aqueous phase. The effectiveness of membrane-assisted organic-aqueous two-phase bioconversions relative to direct-contact two-phase emulsion reactors was demonstrated by Westgate et al. [150]. These authors observed a fivefold increase in the maximum specific activity of hydrolysis of menthyl acetate catalyzed by B. subtilis cells when a 0.2 pm nylon flat membrane reactor was used, as compared to an emulsion reactor. This result was attributed to a continuous interfacial contact, which could only be achieved in an emulsion bioreactor at the cost of high power inputs. Doig and co-workers operated a dense membrane bioreactor for the production of citronellol from geraniol with a product accumulation rate similar to the one obtained in an emulsion reactor [124]. Some examples of membrane-assisted two-liquid phase bio-conversions/fermentations are presented in Table 9. 

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