The Experts below are selected from a list of 252 Experts worldwide ranked by ideXlab platform
Heriberto Espinozagomez - One of the best experts on this subject based on the ideXlab platform.
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development of an enantioselective membrane from Cellulose Acetate propionate Cellulose Acetate for the separation of trans stilbene oxide
Cellulose, 2014Co-Authors: Lucia Z Floreslopez, Jonathan Caloca, Eduardo Rogelhernandez, Heriberto EspinozagomezAbstract:This paper reports the characterization of new synthesized chiral polymeric membranes, based on a Cellulose Acetate propionate polymer. The flux and permselective properties of the membrane were studied using 50 % ethanol solution of (R,S)-trans-stilbene oxide as feed solution. Scanning electron microscopy revealed the asymmetric structure of these membranes. The roughness of the surface was measured by atomic force microscopy. The resolution of over 97 % enantiomeric excess was achieved when the enantioselective membrane was prepared with 18 wt% Cellulose Acetate and 8 wt% Cellulose Acetate propionate in the casting solution of dimethyl formamide/N-methyl-2-pyrrolidone/acetone, at 20 °C and 55 % humidity, and a water bath at 10 °C for the gelation of the membrane. The operating pressure and the feed concentration of the trans-stilbene oxide were 275.57, 345.19, and 413.84 kPa and 2.6 mM, respectively.
Heriberto Espinoza-gomez - One of the best experts on this subject based on the ideXlab platform.
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Development of an enantioselective membrane from Cellulose Acetate propionate/Cellulose Acetate, for the separation of trans-stilbene oxide
Cellulose, 2014Co-Authors: Lucía Z. Flores-lópez, Jonathan Caloca, Eduardo Rogel-hernández, Heriberto Espinoza-gomezAbstract:This paper reports the characterization of new synthesized chiral polymeric membranes, based on a Cellulose Acetate propionate polymer. The flux and permselective properties of the membrane were studied using 50 % ethanol solution of ( R,S )- trans -stilbene oxide as feed solution. Scanning electron microscopy revealed the asymmetric structure of these membranes. The roughness of the surface was measured by atomic force microscopy. The resolution of over 97 % enantiomeric excess was achieved when the enantioselective membrane was prepared with 18 wt% Cellulose Acetate and 8 wt% Cellulose Acetate propionate in the casting solution of dimethyl formamide/ N -methyl-2-pyrrolidone/acetone, at 20 °C and 55 % humidity, and a water bath at 10 °C for the gelation of the membrane. The operating pressure and the feed concentration of the trans -stilbene oxide were 275.57, 345.19, and 413.84 kPa and 2.6 mM, respectively.
Jonathan Caloca - One of the best experts on this subject based on the ideXlab platform.
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Development of an enantioselective membrane from Cellulose Acetate propionate/Cellulose Acetate, for the separation of trans-stilbene oxide
Cellulose, 2014Co-Authors: Lucía Z. Flores-lópez, Jonathan Caloca, Eduardo Rogel-hernández, Heriberto Espinoza-gomezAbstract:This paper reports the characterization of new synthesized chiral polymeric membranes, based on a Cellulose Acetate propionate polymer. The flux and permselective properties of the membrane were studied using 50 % ethanol solution of ( R,S )- trans -stilbene oxide as feed solution. Scanning electron microscopy revealed the asymmetric structure of these membranes. The roughness of the surface was measured by atomic force microscopy. The resolution of over 97 % enantiomeric excess was achieved when the enantioselective membrane was prepared with 18 wt% Cellulose Acetate and 8 wt% Cellulose Acetate propionate in the casting solution of dimethyl formamide/ N -methyl-2-pyrrolidone/acetone, at 20 °C and 55 % humidity, and a water bath at 10 °C for the gelation of the membrane. The operating pressure and the feed concentration of the trans -stilbene oxide were 275.57, 345.19, and 413.84 kPa and 2.6 mM, respectively.
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development of an enantioselective membrane from Cellulose Acetate propionate Cellulose Acetate for the separation of trans stilbene oxide
Cellulose, 2014Co-Authors: Lucia Z Floreslopez, Jonathan Caloca, Eduardo Rogelhernandez, Heriberto EspinozagomezAbstract:This paper reports the characterization of new synthesized chiral polymeric membranes, based on a Cellulose Acetate propionate polymer. The flux and permselective properties of the membrane were studied using 50 % ethanol solution of (R,S)-trans-stilbene oxide as feed solution. Scanning electron microscopy revealed the asymmetric structure of these membranes. The roughness of the surface was measured by atomic force microscopy. The resolution of over 97 % enantiomeric excess was achieved when the enantioselective membrane was prepared with 18 wt% Cellulose Acetate and 8 wt% Cellulose Acetate propionate in the casting solution of dimethyl formamide/N-methyl-2-pyrrolidone/acetone, at 20 °C and 55 % humidity, and a water bath at 10 °C for the gelation of the membrane. The operating pressure and the feed concentration of the trans-stilbene oxide were 275.57, 345.19, and 413.84 kPa and 2.6 mM, respectively.
Li-ming Yuan - One of the best experts on this subject based on the ideXlab platform.
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Enantioseparation of trans-stilbene oxide using a Cellulose Acetate membrane
Journal of Membrane Science, 2009Co-Authors: Min Zhao, Wen-fang Wang, Wen-zhuo Sun, Yun-dong Jiang, Li-ming YuanAbstract:Abstract An enantioselective membrane was prepared using Cellulose Acetate as the membrane material. Cellulose Acetate was chosen as it is in widespread use already for separations and Cellulose triAcetate is the first practical chiral stationary phase of polysaccharide due to the multichiral carbons in its molecular structure unit. The flux and permselective properties of a membrane was studied using a 33.3% ethanol solution of (R, S)-trans-stilbene oxide as the feed solution. The top surface and cross-section morphology of the resulting membrane were examined using scanning electron microscopy. An optical resolution of over 85% enantiomeric excess was achieved when the enantioselective membrane was prepared with 30 wt.% Cellulose Acetate and 25 wt.% N,N-dimethylformamide in the casting solution of acetone; 5 min was the time for evaporation of the liquid membrane, and a 10 °C water bath was used for the gelation of the membrane; the operating pressure and the feed concentration of the trans-stilbene oxide were 2 kgf/cm2 and 0.5 mg/L, respectively. This is the first report that Cellulose Acetate can be used as a membrane material for isolating optical isomers. This work indicates that the large-scale purification of chiral molecules from racemic mixtures will be realized by the enantioselective membrane technique in the near future and that the enantioselective Cellulose Acetate membrane could soon become very attractive for industrial uses.
Lucía Z. Flores-lópez - One of the best experts on this subject based on the ideXlab platform.
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Development of an enantioselective membrane from Cellulose Acetate propionate/Cellulose Acetate, for the separation of trans-stilbene oxide
Cellulose, 2014Co-Authors: Lucía Z. Flores-lópez, Jonathan Caloca, Eduardo Rogel-hernández, Heriberto Espinoza-gomezAbstract:This paper reports the characterization of new synthesized chiral polymeric membranes, based on a Cellulose Acetate propionate polymer. The flux and permselective properties of the membrane were studied using 50 % ethanol solution of ( R,S )- trans -stilbene oxide as feed solution. Scanning electron microscopy revealed the asymmetric structure of these membranes. The roughness of the surface was measured by atomic force microscopy. The resolution of over 97 % enantiomeric excess was achieved when the enantioselective membrane was prepared with 18 wt% Cellulose Acetate and 8 wt% Cellulose Acetate propionate in the casting solution of dimethyl formamide/ N -methyl-2-pyrrolidone/acetone, at 20 °C and 55 % humidity, and a water bath at 10 °C for the gelation of the membrane. The operating pressure and the feed concentration of the trans -stilbene oxide were 275.57, 345.19, and 413.84 kPa and 2.6 mM, respectively.