China
Africa
Explore chapters and articles related to this topic
Frequently Used Membrane Processing Techniques for Food Manufacturing Industries
Published in M. Selvamuthukumaran, Applications of Membrane Technology for Food Processing Industries, 2020
Ulaş Baysan, Necmiye Öznur Çoşkun, Feyza Elmas, Mehmet Koç
Pervaporation can be used as an alternative to conventional separation processes such as steam distillation, liquid solvent extraction, and vacuum distillation. The advantage of this method is that energy consumption is generally lower, no chemical additives are needed, and it can be operated at the low temperatures when separating sensitive aroma compounds (Olmo et al., 2014).
Membrane Separation Processes
Published in Louis Theodore, R. Ryan Dupont, Water Resource Management Issues, 2019
Louis Theodore, R. Ryan Dupont
Pervaporation (PER) is a separation process in which a liquid mixture contacts a nonporous, semipermeable membrane. One component is transported through the membrane preferentially. It evaporates on the downstream side of the membrane, leaving as a vapor. The process is induced by lowering the partial pressure of the permeating component, usually by a vacuum or occasionally with an inert gas. The permeated component is then condensed or recovered as the product of interest.
Bioethanol
Published in Debabrata Das, Jhansi L. Varanasi, Fundamentals of Biofuel Production Processes, 2019
Debabrata Das, Jhansi L. Varanasi
Pervaporation is another in situ recovery method that can be used for ethanol separation from fermentation broths. It is basically a combination of membrane permeation and evaporation techniques (Aroujalian and Raisi 2009). In this method, a porous hydrophobic membrane is used such that ethanol is recovered by adsorption on the membrane followed by diffusion to the permeate side (Figure 9.2c). Ethanol is then recovered through evaporation by applying a vacuum at the permeate side (Jesús Mendoza-Pedroza and Gabriel Segovia-Hernandez 2018). The most common membranes used for pervaporation include organic polymeric membrane (such as polydimethylsiloxane) and inorganic membranes (such as zeolites) (Peng et al. 2010). It is possible to concentrate up to 80%–99% bioethanol using pervaporation technique, however. The limitation of this process includes membrane fouling and low selectivity, which limits its effective application in fermentation industries.
Chitosan-based mixed matrix membranes: effect of different fillers on membrane properties and performance in hydrophilic pervaporation
Published in Chemical Engineering Communications, 2023
Wendel P. Silvestre, Jocelei Duarte, Camila Baldasso, Isabel C. Tessaro
Pervaporation is a membrane separation process in which a chemical potential difference is established between membrane sides to carry out the permeation and transfer of the substances with more affinity with the membrane from the feed to the permeate stream. Generally, this chemical potential difference is established by applying a pressure difference (vacuum) between membrane sides, with a smaller absolute pressure downstream of the membrane (Figoli et al. 2015; Jyoti et al. 2015). The industrial interest in pervaporation is recent. This process has great potential to be used in the separation/purification of thermolabile substances, i.e., those that decompose/degrade at high temperatures, and in the separation of azeotropes. The main feature of pervaporation in the presence of a specific membrane that is selective (i.e., more permeable to sorption and diffusion) to one or some of the components of the feed, results in a permeate stream richer in the substances with more affinity to the membrane (Jyoti et al. 2015; Ong et al. 2016; Cheng et al. 2017; Silvestre et al. 2020; Silvestre et al. 2022a).
Pervaporation separation of ethylacetate-ethanol mixtures using zeolite 13X-filled poly(dimethylsiloxane) membrane
Published in Chemical Engineering Communications, 2022
Sebnem Senol, Buket Kaya, Inci Salt, Berk Tirnakci, Yavuz Salt
Ethyl acetate is an important chemical compound in many areas such as adhesives, leather varnishes, inks, fast-drying paints, photo films, transparent paper production, varnishes, pharmaceutical and organic syntheses. It can be produced from ethanol and acetic acid in either continuous or batch processes by the Fischer esterification reaction and the ethanol dehydrogenation method, respectively. Ethanol and ethyl acetate form an azeotropic mixture, that is difficult to separate using conventional methods (Zhang et al. 2017; Alamaria et al. 2019). Pervaporation (PV) method in which the transport mechanism through a non-porous membrane is based on the solution-diffusion model is recognized as an efficient membrane separation process that can be used for the separation of azeotropic systems or the mixtures containing components with similar boiling points (Lipnizki et al. 1999; Baker 2004; Uragami et al. 2010).