The Experts below are selected from a list of 4146 Experts worldwide ranked by ideXlab platform
Zeyi Xiao - One of the best experts on this subject based on the ideXlab platform.
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kinetic model of continuous ethanol fermentation in closed circulating process with Pervaporation Membrane bioreactor by saccharomyces cerevisiae
Bioresource Technology, 2015Co-Authors: Shiping Chen, Zeyi Xiao, Xiaoyu Tang, Qing Deng, Yan Zhang, Chunyan ChenAbstract:Abstract Unstructured kinetic models were proposed to describe the principal kinetics involved in ethanol fermentation in a continuous and closed-circulating fermentation (CCCF) process with a Pervaporation Membrane bioreactor. After ethanol was removed in situ from the broth by the Membrane Pervaporation, the secondary metabolites accumulated in the broth became the inhibitors to cell growth. The cell death rate related to the deterioration of the culture environment was described as a function of the cell concentration and fermentation time. In CCCF process, 609.8 g L−1 and 750.1 g L−1 of ethanol production were obtained in the first run and second run, respectively. The modified Gompertz model, correlating the ethanol production with the fermentation period, could be used to describe the ethanol production during CCCF process. The fitting results by the models showed good agreement with the experimental data. These models could be employed for the CCCF process technology development for ethanol fermentation.
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continuous ethanol fermentation in a closed circulating system using an immobilized cell coupled with pdms Membrane Pervaporation
Journal of Chemical Technology & Biotechnology, 2011Co-Authors: Wenwu Ding, Xiaoyu Tang, Lin Yuan, Zeyi XiaoAbstract:BACKGROUND: A closed-circulating system for ethanol fermentation was constructed by coupling a cell-immobilized bed fermentor with Pervaporation using a composite PDMS Membrane. A continuous fermentation experiment was carried out for about 250 h in the system at 28 °C. RESULTS: The cell density in the immobilized bed was up to 1.76 × 1010 cells g−1 gel. The ethanol concentration in the broth was maintained at about 43 g L−1. The glucose utilization and ethanol productivity were 23.26 g L−1 h−1 and 9.6 g L−1 h−1, respectively. The total flux and the ethanol flux through the Membrane Pervaporation unit varied in the range 300–690 g m−2 h−1 and 61–190 g m−2 h−1, respectively. The average ethanol concentration in the permeate was 23.1% (wt%). The carbon recovery efficiency was 86.8% (wt%), determined by calculating the carbon balance kinetics. The effect of ethanol concentration in the broth on the ethanol productivity was analyzed by modeling product formation kinetics of the system. CONCLUSIONS: Compared with the traditional free cell fermentation system and packed bed fermentation system, the closed-circulating system has the promising features of higher glucose utilization and ethanol productivity, and cleaner production. Copyright © 2010 Society of Chemical Industry
Robert Y M Huang - One of the best experts on this subject based on the ideXlab platform.
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liquid separation by Membrane Pervaporation a review
Industrial & Engineering Chemistry Research, 1997Co-Authors: Xianshe Feng, Robert Y M HuangAbstract:Pervaporation is one of the most active areas in Membrane research, and the Pervaporation process has been shown to be an indispensable component for chemical separations. In this paper, the recent development in Pervaporation Membranes and Pervaporation processes is reviewed, and some outstanding questions involved in Membrane Pervaporation are discussed with emphasis on the following issues: mass transport in the Membrane, Membrane material selection, concentration polarization in the boundary layer, pressure buildup in hollow fiber Membranes, asymmetric and composite Membranes, and the activation energy for permeation. We attempt to provide insight into this dynamic field and to highlight some of the outstanding problems yet to be solved or clarified.
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Pervaporation with chitosan Membranes i separation of water from ethylene glycol by a chitosan polysulfone composite Membrane
Journal of Membrane Science, 1996Co-Authors: Xianshe Feng, Robert Y M HuangAbstract:Abstract A chitosan/polysulfone composite Membrane was prepared. The preparation procedure involved dissolution of chitosan in dilute aqueous acetic acid to form chitosan salt, coating of the chitosan salt solution on a porous polysulfone substrate, and regeneration of chitosan by alkaline treatment. The Membrane was tested for selective removal of water from aqueous ethylene glycol solutions by Pervaporation. The effects of operating parameters, including feed concentration, temperature, and downstream pressure, on the separation performance of the Membrane were investigated. At 35°C and 60 Pa downstream pressure, a permeation flux of 0.3 kg/m2 h and permeate water concentration higher than 92 wt% was achieved at a feed water content of 10 wt%. This study demonstrated the potential of Membrane Pervaporation as an alternative to conventional distillation for the given separation. It was also shown that conditioning of the Membrane in the Pervaporation system at the maximum operating temperature led to a quasi-permanent change in Membrane permselectivity.
Xiaoyu Tang - One of the best experts on this subject based on the ideXlab platform.
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kinetic model of continuous ethanol fermentation in closed circulating process with Pervaporation Membrane bioreactor by saccharomyces cerevisiae
Bioresource Technology, 2015Co-Authors: Shiping Chen, Zeyi Xiao, Xiaoyu Tang, Qing Deng, Yan Zhang, Chunyan ChenAbstract:Abstract Unstructured kinetic models were proposed to describe the principal kinetics involved in ethanol fermentation in a continuous and closed-circulating fermentation (CCCF) process with a Pervaporation Membrane bioreactor. After ethanol was removed in situ from the broth by the Membrane Pervaporation, the secondary metabolites accumulated in the broth became the inhibitors to cell growth. The cell death rate related to the deterioration of the culture environment was described as a function of the cell concentration and fermentation time. In CCCF process, 609.8 g L−1 and 750.1 g L−1 of ethanol production were obtained in the first run and second run, respectively. The modified Gompertz model, correlating the ethanol production with the fermentation period, could be used to describe the ethanol production during CCCF process. The fitting results by the models showed good agreement with the experimental data. These models could be employed for the CCCF process technology development for ethanol fermentation.
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continuous ethanol fermentation in a closed circulating system using an immobilized cell coupled with pdms Membrane Pervaporation
Journal of Chemical Technology & Biotechnology, 2011Co-Authors: Wenwu Ding, Xiaoyu Tang, Lin Yuan, Zeyi XiaoAbstract:BACKGROUND: A closed-circulating system for ethanol fermentation was constructed by coupling a cell-immobilized bed fermentor with Pervaporation using a composite PDMS Membrane. A continuous fermentation experiment was carried out for about 250 h in the system at 28 °C. RESULTS: The cell density in the immobilized bed was up to 1.76 × 1010 cells g−1 gel. The ethanol concentration in the broth was maintained at about 43 g L−1. The glucose utilization and ethanol productivity were 23.26 g L−1 h−1 and 9.6 g L−1 h−1, respectively. The total flux and the ethanol flux through the Membrane Pervaporation unit varied in the range 300–690 g m−2 h−1 and 61–190 g m−2 h−1, respectively. The average ethanol concentration in the permeate was 23.1% (wt%). The carbon recovery efficiency was 86.8% (wt%), determined by calculating the carbon balance kinetics. The effect of ethanol concentration in the broth on the ethanol productivity was analyzed by modeling product formation kinetics of the system. CONCLUSIONS: Compared with the traditional free cell fermentation system and packed bed fermentation system, the closed-circulating system has the promising features of higher glucose utilization and ethanol productivity, and cleaner production. Copyright © 2010 Society of Chemical Industry
Xianshe Feng - One of the best experts on this subject based on the ideXlab platform.
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liquid separation by Membrane Pervaporation a review
Industrial & Engineering Chemistry Research, 1997Co-Authors: Xianshe Feng, Robert Y M HuangAbstract:Pervaporation is one of the most active areas in Membrane research, and the Pervaporation process has been shown to be an indispensable component for chemical separations. In this paper, the recent development in Pervaporation Membranes and Pervaporation processes is reviewed, and some outstanding questions involved in Membrane Pervaporation are discussed with emphasis on the following issues: mass transport in the Membrane, Membrane material selection, concentration polarization in the boundary layer, pressure buildup in hollow fiber Membranes, asymmetric and composite Membranes, and the activation energy for permeation. We attempt to provide insight into this dynamic field and to highlight some of the outstanding problems yet to be solved or clarified.
-
Pervaporation with chitosan Membranes i separation of water from ethylene glycol by a chitosan polysulfone composite Membrane
Journal of Membrane Science, 1996Co-Authors: Xianshe Feng, Robert Y M HuangAbstract:Abstract A chitosan/polysulfone composite Membrane was prepared. The preparation procedure involved dissolution of chitosan in dilute aqueous acetic acid to form chitosan salt, coating of the chitosan salt solution on a porous polysulfone substrate, and regeneration of chitosan by alkaline treatment. The Membrane was tested for selective removal of water from aqueous ethylene glycol solutions by Pervaporation. The effects of operating parameters, including feed concentration, temperature, and downstream pressure, on the separation performance of the Membrane were investigated. At 35°C and 60 Pa downstream pressure, a permeation flux of 0.3 kg/m2 h and permeate water concentration higher than 92 wt% was achieved at a feed water content of 10 wt%. This study demonstrated the potential of Membrane Pervaporation as an alternative to conventional distillation for the given separation. It was also shown that conditioning of the Membrane in the Pervaporation system at the maximum operating temperature led to a quasi-permanent change in Membrane permselectivity.
Chunyan Chen - One of the best experts on this subject based on the ideXlab platform.
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kinetic model of continuous ethanol fermentation in closed circulating process with Pervaporation Membrane bioreactor by saccharomyces cerevisiae
Bioresource Technology, 2015Co-Authors: Shiping Chen, Zeyi Xiao, Xiaoyu Tang, Qing Deng, Yan Zhang, Chunyan ChenAbstract:Abstract Unstructured kinetic models were proposed to describe the principal kinetics involved in ethanol fermentation in a continuous and closed-circulating fermentation (CCCF) process with a Pervaporation Membrane bioreactor. After ethanol was removed in situ from the broth by the Membrane Pervaporation, the secondary metabolites accumulated in the broth became the inhibitors to cell growth. The cell death rate related to the deterioration of the culture environment was described as a function of the cell concentration and fermentation time. In CCCF process, 609.8 g L−1 and 750.1 g L−1 of ethanol production were obtained in the first run and second run, respectively. The modified Gompertz model, correlating the ethanol production with the fermentation period, could be used to describe the ethanol production during CCCF process. The fitting results by the models showed good agreement with the experimental data. These models could be employed for the CCCF process technology development for ethanol fermentation.