The Experts below are selected from a list of 168 Experts worldwide ranked by ideXlab platform
Stan Claes - One of the best experts on this subject based on the ideXlab platform.
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high flux composite ptmsp silica nanohybrid membranes for the Pervaporation of ethanol water mixtures
2010Co-Authors: Pieter Vandezande, Stan Claes, Steven Mullens, Roger Leysen, K De Sitter, Anna Andersson, Frans H J Maurer, H Van Den Rul, Roos PeetersAbstract:Silica-filled poly(1-trimethylsilyl-1-propyne) (PTMSP) layers were successfully applied for the first time on top of ultrafiltration support membranes and applied in the pervaporative separation of ethanol/water mixtures. Reduction of the thickness of the separating PTMSP top layer and addition of hydrophobic silica particles resulted in a clear flux increase as compared to dense PTMSP membranes. With ethanol/water separation factors up to 12 and fluxes up to 3.5 kg m(-2) h(-1), the prepared supported PTMSP-silica nanohybrid membranes performed significantly better than the best commercially available Organophilic Pervaporation membranes. Characterization of a polyvinylidene fluoride (PVDF) and a polyacrylonitrile (PAN) support membrane revealed a more open, irregular and hydrophobic surface structure for the former membrane, thus explaining the higher fluxes of the PTMSP/PVDF composite membrane. Because of their promising flux-selectivity combination, the prepared membranes exhibit great potential in the removal of alcohols from aqueous mixtures. (C) 2010 Elsevier B.V. All rights reserved. (Less)
Yinhua Wan - One of the best experts on this subject based on the ideXlab platform.
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separation performance of novel vinyltriethoxysilane vtes g silicalite 1 pdms pan thin film composite membrane in the recovery of bioethanol from fermentation broths by Pervaporation
2017Co-Authors: Yinhua WanAbstract:Abstract Organophilic Pervaporation (OPV) has been considered as one of the most promising separation processes for the recovery of biofuels from fermentation broths, however, in addition to preferred target product – liquid biofuels, the yeast cells and fermentation nutrients could affect the recovery efficiency of biofuels from broths by Pervaporation. In this paper, the influence of the yeast cells and the fermentation nutrient components such as the sources of carbon, nitrogen and salts on the separation performance of the vinyltriethoxysilane (VTES)-grafted- (VTES-g-) silicalite-1/PDMS/PAN thin-film composite membrane was conducted systematically. The results revealed that glucose, xylose, protein, and salts cannot permeate through the membrane. Glucose concentration in the fermentation broth should be kept at a lower level (less than 20 g/L) to eliminate its deleterious influence on ethanol flux and membrane selectivity. Xylose and corn steep liquor (CSL) have little effect on the Pervaporation performance of the composite membrane. The addition of NaCl improved the membrane selectivity and ethanol flux but slightly lowered down total permeation flux. Adding dry yeast cells to the ethanol solution can enhance the turbulence in the feed mixtures, resulting an increase of the membrane flux and selectivity. The Pervaporation performance of fermentation broths was also studied. The results showed that the nutrients and the deposition of yeast cells on the membrane surface didn’t deteriorate the Pervaporation performance, indicating excellent fouling resistance of the novel VTES-g-silicalite-1/PDMS/PAN composite membrane in operation with fermentation broths. The continuous ethanol fermentation can be directly connected to the in-situ pervaporative recovery system without requiring prior removal of yeast cells.
Yu P Yampolskii - One of the best experts on this subject based on the ideXlab platform.
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intermolecular interactions in target Organophilic Pervaporation through the films of amorphous teflon af2400
2006Co-Authors: A M Polyakov, G N Bondarenko, A V Tokarev, Yu P YampolskiiAbstract:Abstract Organic–organic Pervaporation was studied for high free volume material—amorphous Teflon AF2400 (copolymer of 2,2-bis-trifluoromethyle-4,5-difluoro dioxole and tetrafluoroethylene). Individual organic components—acetone (A), chloroform (Ch) and methanol (M) that are capable of forming azeotrope mixtures as well as binary mixtures A–Ch and M–Ch were tested as penetrants. The process was studied at different temperatures (10–50 °C) over a wide range of composition of mixtures (10–90%). Evidence of formation of associates between the components in the mixtures in the liquid phase and during mass transfer through the films were obtained. IR spectra and quantum-chemical calculations supported these conclusions.
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amorphous teflons af as Organophilic Pervaporation materials separation of mixtures of chloromethanes
2004Co-Authors: A M Polyakov, L E Starannikova, Yu P YampolskiiAbstract:Abstract Pervaporation of binary mixtures (CH 2 Cl 2 –CHCl 3 , CHCl 3 –CCl 4 , CH 2 Cl 2 –CCl 4 ) through two amorphous copolymers of 2,2-bis-trifluoromethyl-4,5-difluoro-1,3-dioxole and tetrafluoroethylene was studied at different temperatures, feed composition, and downstream pressure. It was shown that the copolymer with the larger content of the dioxole comonomer and having the greater free volume (AF 2400) is more permeable, whereas selectivity of separation of the two copolymers are similar for some regimes. The dependence of permeation rate and selectivity on the process parameters of the AF copolymers indicated that mobility selectivity prevails for Pervaporation of the mixtures studied through these membrane materials. The deviation coefficients used for analysis of mixed permeation indicated strong interactions of the components in Pervaporation of binary mixtures. Pervaporation separation index (PSI), which depends on permeability and selectivity of Pervaporation, was used to characterize the performance of the process. It was shown that PSI increases for higher contents of the components enriched in the permeate and at higher temperatures.
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amorphous teflons af as Organophilic Pervaporation materials transport of individual components
2003Co-Authors: A M Polyakov, L E Starannikova, Yu P YampolskiiAbstract:Abstract Permeation and sorption of various organic liquids (chlorinated hydrocarbons, lower alcohols, hydrocarbons, etc.) in amorphous copolymers of 2,2-bis-trifluoromethyl-4,5-difluoro-1,3-dioxole and tetrafluoroethylene (amorphous Teflons AF) were studied in the temperature range 5–95 °C. Based on permeation rate and solubility coefficients, the diffusion coefficients of organic penetrants in AF copolymers AF were estimated. It was shown that the copolymer with a higher content (87%) of the dioxole component (AF2400), as distinguished by a larger free volume, is much more permeable to liquids than the copolymer AF1600 containing 65% of the dioxole comonomer. In contrast, solubility of organic compounds in both copolymers is hardly affected by their composition. The effects of penetrant parameters, such as critical volume ( V c ) and critical temperature ( T c ) were analyzed. The variation in permeation rates of liquids and gases through these materials are consistent with a mobility (diffusion) controlled mechanism for mass transfer. A trade-off between the Arrhenius parameters for permeability and the van’t Hoff parameters for solubility is demonstrated for Pervaporation. On this basis, novel correlations are obtained that enable a determination of the activation energy for permeation E P and the enthalpy of sorption H S from the permeability ( P ) and solubility ( S ) coefficients. Long term tests (up to 12 months) showed excellent time stability of the transport parameters, a property unexpected and quite important for a high flux, high free volume Pervaporation material.
Roos Peeters - One of the best experts on this subject based on the ideXlab platform.
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high flux composite ptmsp silica nanohybrid membranes for the Pervaporation of ethanol water mixtures
2010Co-Authors: Pieter Vandezande, Stan Claes, Steven Mullens, Roger Leysen, K De Sitter, Anna Andersson, Frans H J Maurer, H Van Den Rul, Roos PeetersAbstract:Silica-filled poly(1-trimethylsilyl-1-propyne) (PTMSP) layers were successfully applied for the first time on top of ultrafiltration support membranes and applied in the pervaporative separation of ethanol/water mixtures. Reduction of the thickness of the separating PTMSP top layer and addition of hydrophobic silica particles resulted in a clear flux increase as compared to dense PTMSP membranes. With ethanol/water separation factors up to 12 and fluxes up to 3.5 kg m(-2) h(-1), the prepared supported PTMSP-silica nanohybrid membranes performed significantly better than the best commercially available Organophilic Pervaporation membranes. Characterization of a polyvinylidene fluoride (PVDF) and a polyacrylonitrile (PAN) support membrane revealed a more open, irregular and hydrophobic surface structure for the former membrane, thus explaining the higher fluxes of the PTMSP/PVDF composite membrane. Because of their promising flux-selectivity combination, the prepared membranes exhibit great potential in the removal of alcohols from aqueous mixtures. (C) 2010 Elsevier B.V. All rights reserved. (Less)
Pieter Vandezande - One of the best experts on this subject based on the ideXlab platform.
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biobutanol production from c5 c6 carbohydrates integrated with Pervaporation experimental results and conceptual plant design
2016Co-Authors: Wouter Van Hecke, Pieter Vandezande, Marjorie Dubreuil, Maarten Uyttebroek, Herman Beckers, Heleen De WeverAbstract:In this study, a simulated lignocellulosic hydrolyzate was used in a continuous two-stage fermentor setup for production of acetone, butanol and ethanol. An Organophilic Pervaporation unit was coupled to the second fermentor. The dilution rate in the first fermentor was kept constant at 0.109 h(-1), while the dilution rate in the second fermentor was gradually decreased from 0.056 to 0.020 h(-1). Glucose was completely consumed, while 61% of the xylose was consumed at the lowest dilution rate, leading to an overall solvent productivity of 0.65 g L(-1) h(-1) and a high concentration of 185 g kg(-1) solvents in the permeate in the last fermentation zone during 192 h. Based on the experimental results, a process integrated with Organophilic Pervaporation was conceptually designed and compared with a base-case. Chemcad simulations indicate an energy reduction of ~50% when Organophilic Pervaporation is used. This study also demonstrates significant reductions in process flows and energy consumption by the use of Organophilic Pervaporation as in situ product recovery technology.
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high flux composite ptmsp silica nanohybrid membranes for the Pervaporation of ethanol water mixtures
2010Co-Authors: Pieter Vandezande, Stan Claes, Steven Mullens, Roger Leysen, K De Sitter, Anna Andersson, Frans H J Maurer, H Van Den Rul, Roos PeetersAbstract:Silica-filled poly(1-trimethylsilyl-1-propyne) (PTMSP) layers were successfully applied for the first time on top of ultrafiltration support membranes and applied in the pervaporative separation of ethanol/water mixtures. Reduction of the thickness of the separating PTMSP top layer and addition of hydrophobic silica particles resulted in a clear flux increase as compared to dense PTMSP membranes. With ethanol/water separation factors up to 12 and fluxes up to 3.5 kg m(-2) h(-1), the prepared supported PTMSP-silica nanohybrid membranes performed significantly better than the best commercially available Organophilic Pervaporation membranes. Characterization of a polyvinylidene fluoride (PVDF) and a polyacrylonitrile (PAN) support membrane revealed a more open, irregular and hydrophobic surface structure for the former membrane, thus explaining the higher fluxes of the PTMSP/PVDF composite membrane. Because of their promising flux-selectivity combination, the prepared membranes exhibit great potential in the removal of alcohols from aqueous mixtures. (C) 2010 Elsevier B.V. All rights reserved. (Less)