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Sungyong Mun - One of the best experts on this subject based on the ideXlab platform.
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Optimization of Production rate, Productivity, and Product Concentration for a simulated moving bed process aimed atfucose separation using standing-wave-design and genetic algorithm.
Journal of chromatography. A, 2018Co-Authors: Sungyong MunAbstract:Abstract The effectiveness of a simulated moving bed (SMB) technology in the continuous separation of fucose from a multi-component monosugar mixture, which stemmed from defatted microalgae, has recently been identified. To guarantee high economical efficiency of such fucose-Production method, the comprehensive optimization of the relevant fucose-separation SMB process needs to be accomplished such that its Production rate (Prate) and/or Productivity (Prod) can be maximized while meeting the requirements on fucose Product Concentration (Cprod,F) and pressure drop (ΔPSMB). To resolve this issue, the SMB optimization program based on standing-wave-design method and genetic algorithm was prepared and then applied to the fucose-separation SMB optimization. It was found that the Prate, under a given particle size, could reach its maximum when the column length was selected to create a balance between the effects of the two limiting factors related to Cprod,F and ΔPSMB. It was also found that the Prate was governed by fucose yield, if the SMB would be in need of a relatively high Cprod,F; otherwise, the Prate was governed by feed flow rate. If the particle size of the SMB adsorbent was fixed at one of the commercially available ones, the SMB conditions leading to the highest Prate and the highest Prod coincided with each other. By contrast, if the particle size was included as one of optimization variables, the Prate and Prod represented a trade-off relationship. Finally, it was confirmed from the simultaneous optimization for Prate and Prod that the increase of particle size improved Prate at the cost of Prod, thereby causing the maximum Prod to be always attained at a smaller particle size than the maximum Prate regardless of the target Cprod,F level.
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standing wave design and optimization of a simulated moving bed chromatography for separation of xylobiose and xylose under the constraints on Product Concentration and pressure drop
Journal of Chromatography A, 2017Co-Authors: Chunggi Lee, Nienhwa Linda Wang, Jaehwan Choi, Chanhun Park, Sungyong MunAbstract:The feasibility of a simulated moving bed (SMB) technology for the continuous separation of high-purity xylobiose (X2) from the output of a β-xylosidase X1→X2 reaction has recently been confirmed. To ensure high economical efficiency of the X2 Production method based on the use of xylose (X1) as a starting material, it is essential to accomplish the comprehensive optimization of the X2-separation SMB process in such a way that its X2 Productivity can be maximized while maintaining the X2 Product Concentration from the SMB as high as possible in consideration of a subsequent lyophilization step. To address this issue, a suitable SMB optimization tool for the aforementioned task was prepared based on standing wave design theory. The prepared tool was then used to optimize the SMB operation parameters, column configuration, total column number, adsorbent particle size, and X2 yield while meeting the constraints on X2 purity, X2 Product Concentration, and pressure drop. The results showed that the use of a larger particle size caused the Productivity to be limited by the constraint on X2 Product Concentration, and a maximum Productivity was attained by choosing the particle size such that the effect of the X2-Concentration limiting factor could be balanced with that of pressure-drop limiting factor. If the target level of X2 Product Concentration was elevated, higher Productivity could be achieved by decreasing particle size, raising the level of X2 yield, and increasing the column number in the zones containing the front and rear of X2 solute band.
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Development of a three-zone simulated moving bed process based on partial-discard strategy for continuous separation of valine from isoleucine with high purity, high yield, and high Product Concentration
Process Biochemistry, 2014Co-Authors: Chanhun Park, Hee-geun Nam, Hee-jeong Hwang, Jin-hyun Kim, Sungyong MunAbstract:Abstract The issue of separating valine from isoleucine has been a major concern in the biotechnological process for Production of valine. To address this issue, an optimal three-zone simulated moving bed (SMB) process for continuous separation of valine was developed in this study. It was first found that an Amberchrom-CG161C resin was highly suitable for the adsorbent of such SMB process. The adsorption isotherm and mass-transfer parameters of valine and isoleucine on the Amberchrom-CG161C adsorbent were then determined through multiple frontal experiments. The determined parameters were used in the next stage of optimizing the SMB for valine separation, which was performed on the basis of genetic algorithm. For the optimized SMB process, a partial-discard strategy was applied to the raffinate port in order to make a further improvement in the valine Product Concentration. Finally, the optimized SMB based on the partial-discard strategy was tested experimentally using the self-assembled SMB equipment. The experimental results showed that the developed process in this study was highly effective in continuous separation of valine from isoleucine while ensuring the attainment of high Product Concentration. The experimental data for the SMB effluent histories and the SMB column profiles were also in close agreement with the model predictions.
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Consideration of a target Product Concentration level in the optimal design of a four-zone simulated moving bed process for binary separation
Chemical Engineering Journal, 2012Co-Authors: Sungyong MunAbstract:Abstract In the stage of optimizing a simulated moving bed (SMB) process for continuous separation, the extent of Product Concentration can sometimes be as important as the other performance criteria such as throughput and Product purities. In such cases, the issue of maintaining the Product Concentration higher than a given target level needs to be taken into account during the SMB optimization. To investigate this issue, the throughput of an SMB process for binary separation was optimized in this study using a model separation system while placing a constraint on Product Concentration as well as pressure drop. The resultant throughput from such SMB optimization was highly affected by column length. It was found first that the throughput was limited by the constraint on the Product Concentration in the region of short columns but limited by the constraint on the pressure drop in the region of long columns. As a result, the optimal column length leading to the highest throughput occurred at the boundary between the Product-Concentration limiting region and the pressure-drop limiting region. In addition to the column length, the column configuration also played an important role in the optimization of the SMB with the constraint on the Product Concentration. As the target level of the raffinate Product Concentration was set higher, the optimal column configuration leading to the maximum throughput showed the pattern of placing more columns in zone IV. By contrast, the placement of more columns in zone I became the pattern of optimal column configuration when the target level of the extract Product Concentration was set higher. The results and methodology in this article will be useful when there is a necessity for developing SMBs that are to meet a certain requirement imposed on Product Concentration.
Nienhwa Linda Wang - One of the best experts on this subject based on the ideXlab platform.
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standing wave design and optimization of a simulated moving bed chromatography for separation of xylobiose and xylose under the constraints on Product Concentration and pressure drop
Journal of Chromatography A, 2017Co-Authors: Chunggi Lee, Nienhwa Linda Wang, Jaehwan Choi, Chanhun Park, Sungyong MunAbstract:The feasibility of a simulated moving bed (SMB) technology for the continuous separation of high-purity xylobiose (X2) from the output of a β-xylosidase X1→X2 reaction has recently been confirmed. To ensure high economical efficiency of the X2 Production method based on the use of xylose (X1) as a starting material, it is essential to accomplish the comprehensive optimization of the X2-separation SMB process in such a way that its X2 Productivity can be maximized while maintaining the X2 Product Concentration from the SMB as high as possible in consideration of a subsequent lyophilization step. To address this issue, a suitable SMB optimization tool for the aforementioned task was prepared based on standing wave design theory. The prepared tool was then used to optimize the SMB operation parameters, column configuration, total column number, adsorbent particle size, and X2 yield while meeting the constraints on X2 purity, X2 Product Concentration, and pressure drop. The results showed that the use of a larger particle size caused the Productivity to be limited by the constraint on X2 Product Concentration, and a maximum Productivity was attained by choosing the particle size such that the effect of the X2-Concentration limiting factor could be balanced with that of pressure-drop limiting factor. If the target level of X2 Product Concentration was elevated, higher Productivity could be achieved by decreasing particle size, raising the level of X2 yield, and increasing the column number in the zones containing the front and rear of X2 solute band.
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standing wave design of tandem smb for linear multicomponent systems
Aiche Journal, 2002Co-Authors: Benjamin J Hritzko, Robert J Wooley, Nienhwa Linda WangAbstract:The standing-wave design was extended to achieve any desired split of mixtures containing three or more components in a single-ring and a tandem two-ring simulated moving bed (SMB). Mass-transfer effects were considered in the design for nonideal systems. The separation of a four-component mixture of glucose, xylose, acetic acid and sulfuric acid was chosen to illustrate the design method. Rate-model simulations confirmed that the standing-wave design method could guarantee high purity and high yield. If all the components in a ternary mixture need to be recovered with high purity and high yield, the easier separation should be performed in the first ring of a tandem SMB to achieve the lowest desorbent consumption and the highest Product Concentration. If only the intermediate component needs to be recovered in high purity, one of the impurities should be allowed to distribute between the two Product ports in the first ring to achieve a lower desorbent consumption and a higher Product Concentration. These strategies also apply to the separation of a mixture containing more than three components.
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Standing‐wave design of tandem SMB for linear multicomponent systems
Aiche Journal, 2002Co-Authors: Benjamin J Hritzko, Robert J Wooley, Nienhwa Linda WangAbstract:The standing-wave design was extended to achieve any desired split of mixtures containing three or more components in a single-ring and a tandem two-ring simulated moving bed (SMB). Mass-transfer effects were considered in the design for nonideal systems. The separation of a four-component mixture of glucose, xylose, acetic acid and sulfuric acid was chosen to illustrate the design method. Rate-model simulations confirmed that the standing-wave design method could guarantee high purity and high yield. If all the components in a ternary mixture need to be recovered with high purity and high yield, the easier separation should be performed in the first ring of a tandem SMB to achieve the lowest desorbent consumption and the highest Product Concentration. If only the intermediate component needs to be recovered in high purity, one of the impurities should be allowed to distribute between the two Product ports in the first ring to achieve a lower desorbent consumption and a higher Product Concentration. These strategies also apply to the separation of a mixture containing more than three components.
Benjamin J Hritzko - One of the best experts on this subject based on the ideXlab platform.
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standing wave design of tandem smb for linear multicomponent systems
Aiche Journal, 2002Co-Authors: Benjamin J Hritzko, Robert J Wooley, Nienhwa Linda WangAbstract:The standing-wave design was extended to achieve any desired split of mixtures containing three or more components in a single-ring and a tandem two-ring simulated moving bed (SMB). Mass-transfer effects were considered in the design for nonideal systems. The separation of a four-component mixture of glucose, xylose, acetic acid and sulfuric acid was chosen to illustrate the design method. Rate-model simulations confirmed that the standing-wave design method could guarantee high purity and high yield. If all the components in a ternary mixture need to be recovered with high purity and high yield, the easier separation should be performed in the first ring of a tandem SMB to achieve the lowest desorbent consumption and the highest Product Concentration. If only the intermediate component needs to be recovered in high purity, one of the impurities should be allowed to distribute between the two Product ports in the first ring to achieve a lower desorbent consumption and a higher Product Concentration. These strategies also apply to the separation of a mixture containing more than three components.
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Standing‐wave design of tandem SMB for linear multicomponent systems
Aiche Journal, 2002Co-Authors: Benjamin J Hritzko, Robert J Wooley, Nienhwa Linda WangAbstract:The standing-wave design was extended to achieve any desired split of mixtures containing three or more components in a single-ring and a tandem two-ring simulated moving bed (SMB). Mass-transfer effects were considered in the design for nonideal systems. The separation of a four-component mixture of glucose, xylose, acetic acid and sulfuric acid was chosen to illustrate the design method. Rate-model simulations confirmed that the standing-wave design method could guarantee high purity and high yield. If all the components in a ternary mixture need to be recovered with high purity and high yield, the easier separation should be performed in the first ring of a tandem SMB to achieve the lowest desorbent consumption and the highest Product Concentration. If only the intermediate component needs to be recovered in high purity, one of the impurities should be allowed to distribute between the two Product ports in the first ring to achieve a lower desorbent consumption and a higher Product Concentration. These strategies also apply to the separation of a mixture containing more than three components.
Christopher W Mcintyre - One of the best experts on this subject based on the ideXlab platform.
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tissue advanced glycation end Product Concentration in dialysis patients
Clinical Journal of The American Society of Nephrology, 2010Co-Authors: Natasha J Mcintyre, Lindsay J Chesterton, Stephen G John, Helen J Jefferies, James O Burton, Maarten W Taal, Richard Fluck, Christopher W McintyreAbstract:BACKGROUND AND OBJECTIVES: Tissue-advanced glycation end Products (AGE) are a measure of cumulative metabolic stress. Assessment of tissue AGE by skin autofluoresence (AF) correlates well with cardiovascular outcomes in hemodialysis (HD) patients. This study aimed to measure and compare tissue AGE levels in HD and peritoneal dialysis (PD) patients and to evaluate the impact of systemic PD glucose exposure. DESIGN, SETTING, PARTICIPANTS, & MEASUREMENTS: Tissue AGE were measured in 115 established dialysis patients (62 HD and 53 PD) using a cutaneous AF device (AGE Reader; DiagnOptics). Values were compared with an age-matched non-chronic kidney disease database. Review of all previous PD solution delivery/prescription data determined PD glucose exposure. RESULTS: PD patients were similar in age to HD patients but had a shorter dialysis vintage. There were no differences in ischemic heart disease or smoking history, statin or angiotensin-converting enzyme inhibitor (ACEi) use, lipids, biochemistry, or prevalence of diabetes. More than 90% of both groups had met current dialysis adequacy targets. Skin AF values in PD and HD patients were similar and strongly correlated with historical PD glucose exposure. Skin AF correlated with age in both groups but with dialysis vintage only in PD patients CONCLUSIONS: Cumulative metabolic stress and transient hyperglycemia results in grossly elevated levels of tissue AGE in dialysis patients. In PD patients, this high level of AGE deposition is associated with historical glucose exposure. This observation provides a previously unappreciated potential link between PD exposure to glucose and systemic cardiovascular disease.
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Tissue-advanced glycation end Product Concentration in dialysis patients.
Clinical journal of the American Society of Nephrology : CJASN, 2009Co-Authors: Natasha J Mcintyre, Lindsay J Chesterton, Stephen G John, Helen J Jefferies, James O Burton, Maarten W Taal, Richard Fluck, Christopher W McintyreAbstract:Background and objectives: Tissue-advanced glycation end Products (AGE) are a measure of cumulative metabolic stress. Assessment of tissue AGE by skin autofluoresence (AF) correlates well with cardiovascular outcomes in hemodialysis (HD) patients. This study aimed to measure and compare tissue AGE levels in HD and peritoneal dialysis (PD) patients and to evaluate the impact of systemic PD glucose exposure. Design, setting, participants, & measurements: Tissue AGE were measured in 115 established dialysis patients (62 HD and 53 PD) using a cutaneous AF device (AGE Reader; DiagnOptics). Values were compared with an age-matched non–chronic kidney disease database. Review of all previous PD solution delivery/prescription data determined PD glucose exposure. Results: PD patients were similar in age to HD patients but had a shorter dialysis vintage. There were no differences in ischemic heart disease or smoking history, statin or angiotensin-converting enzyme inhibitor (ACEi) use, lipids, biochemistry, or prevalence of diabetes. More than 90% of both groups had met current dialysis adequacy targets. Skin AF values in PD and HD patients were similar and strongly correlated with historical PD glucose exposure. Skin AF correlated with age in both groups but with dialysis vintage only in PD patients Conclusions: Cumulative metabolic stress and transient hyperglycemia results in grossly elevated levels of tissue AGE in dialysis patients. In PD patients, this high level of AGE deposition is associated with historical glucose exposure. This observation provides a previously unappreciated potential link between PD exposure to glucose and systemic cardiovascular disease. Clin J Am Soc Nephrol 5: 51–55, 2010. doi: 10.2215/CJN.05350709
Chanhun Park - One of the best experts on this subject based on the ideXlab platform.
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standing wave design and optimization of a simulated moving bed chromatography for separation of xylobiose and xylose under the constraints on Product Concentration and pressure drop
Journal of Chromatography A, 2017Co-Authors: Chunggi Lee, Nienhwa Linda Wang, Jaehwan Choi, Chanhun Park, Sungyong MunAbstract:The feasibility of a simulated moving bed (SMB) technology for the continuous separation of high-purity xylobiose (X2) from the output of a β-xylosidase X1→X2 reaction has recently been confirmed. To ensure high economical efficiency of the X2 Production method based on the use of xylose (X1) as a starting material, it is essential to accomplish the comprehensive optimization of the X2-separation SMB process in such a way that its X2 Productivity can be maximized while maintaining the X2 Product Concentration from the SMB as high as possible in consideration of a subsequent lyophilization step. To address this issue, a suitable SMB optimization tool for the aforementioned task was prepared based on standing wave design theory. The prepared tool was then used to optimize the SMB operation parameters, column configuration, total column number, adsorbent particle size, and X2 yield while meeting the constraints on X2 purity, X2 Product Concentration, and pressure drop. The results showed that the use of a larger particle size caused the Productivity to be limited by the constraint on X2 Product Concentration, and a maximum Productivity was attained by choosing the particle size such that the effect of the X2-Concentration limiting factor could be balanced with that of pressure-drop limiting factor. If the target level of X2 Product Concentration was elevated, higher Productivity could be achieved by decreasing particle size, raising the level of X2 yield, and increasing the column number in the zones containing the front and rear of X2 solute band.
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Development of a three-zone simulated moving bed process based on partial-discard strategy for continuous separation of valine from isoleucine with high purity, high yield, and high Product Concentration
Process Biochemistry, 2014Co-Authors: Chanhun Park, Hee-geun Nam, Hee-jeong Hwang, Jin-hyun Kim, Sungyong MunAbstract:Abstract The issue of separating valine from isoleucine has been a major concern in the biotechnological process for Production of valine. To address this issue, an optimal three-zone simulated moving bed (SMB) process for continuous separation of valine was developed in this study. It was first found that an Amberchrom-CG161C resin was highly suitable for the adsorbent of such SMB process. The adsorption isotherm and mass-transfer parameters of valine and isoleucine on the Amberchrom-CG161C adsorbent were then determined through multiple frontal experiments. The determined parameters were used in the next stage of optimizing the SMB for valine separation, which was performed on the basis of genetic algorithm. For the optimized SMB process, a partial-discard strategy was applied to the raffinate port in order to make a further improvement in the valine Product Concentration. Finally, the optimized SMB based on the partial-discard strategy was tested experimentally using the self-assembled SMB equipment. The experimental results showed that the developed process in this study was highly effective in continuous separation of valine from isoleucine while ensuring the attainment of high Product Concentration. The experimental data for the SMB effluent histories and the SMB column profiles were also in close agreement with the model predictions.
