The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） ...The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr（VI） adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature.展开更多
The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic micro...The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic microspheres were investigated by FT-IR spectrometer, dynamic laser scattering analyzer and scanning electron microscope, respectively. Bovine serum album(BSA)was chosen as model protein, and the adsorption processes were carried out under diversified conditions including BSA initial concentration, p H value, adsorption time and temperature to evaluate the performance of the magnetic microspheres. The average diameter of optimized spherical magnetic microspheres is 1.6 μm with excellent dispersivity, and the saturation magnetization is found to be equal to 1.056×10-2 A·m2. The adsorption isotherm of the BSA on the magnetic microspheres basically obeys the Langmuir model, with a maximum adsorption capacity of 120 mg/g and an adsorption equilibrium constant of 1.60 mL/mg.展开更多
In this study, quaternized chitosan microspheres （QCMS） were prepared and its Cr （VI） removal potential was investigated. Batch experiments were conducted to examine kinetics, adsorption isotherm, pH effect, and t...In this study, quaternized chitosan microspheres （QCMS） were prepared and its Cr （VI） removal potential was investigated. Batch experiments were conducted to examine kinetics, adsorption isotherm, pH effect, and thermodynamic parameters. Equilibrium was attained within 50 rain and maximum removal of 97.34% was achieved under the optimum conditions at pH 5. Adsorption data for Cr （VI） uptake by the QCMS were analyzed according to Langmuir, Freundlich, and Temkin adsorption models. The maximum uptake of Cr （VI） was 39.1 mg.g-a. Thermodynamic parameters for the adsorption system were determinated at 293 K, 303 K, 313 K and 323 K. （AH° = 16.08 kJ.mol- 1;AG° = -5.84 to -8.08 kJ.mo1-1 and AS° = 74.81 J.K-1 .tool-l）. So the positive values of both A/-F and AS° suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption. AG° values obtained were negative indicating a spontaneous adsorp- tion process. The kinetic process was described by a pseudo-second-order rate equation very well. The results of the present study indicated that the QCMS could he considered as a potential adsorbent for Cr （V1） in aqueous solutions.展开更多
In this work, an equilibrium-dispersion model was successfully established to describe the breakthrough performance of Ca（Ⅱ） imprinted chitosan （Ca（Ⅱ）-CS） microspheres packed column for metal adsorption, and t...In this work, an equilibrium-dispersion model was successfully established to describe the breakthrough performance of Ca（Ⅱ） imprinted chitosan （Ca（Ⅱ）-CS） microspheres packed column for metal adsorption, and the assumptions of Langmuir isotherms and axial dispersion controlled mass transfer process were confirmed. The axial dispersion coefficient in Ca（Ⅱ）-CS microspheres packed column was found to be almost proportional to the linear velocity and fit for prediction through single breakthrough test. Sensitivity analysis for breakthrough curve indicated the axial dispersion coefficient as well as Langmuir coefficient was sensitive variable for deep removal requirement. The retrieval of the adsorption isotherms of Ca（Ⅱ）-CS microspheres from breakthrough curve was fulfilled by modelling calibration. A strategy based on the correlation between adsorption isotherms and breakthrough performance was further proposed to simplify the column adsorption design using absorbents with small/uniform size and fast adsorption kinetics like Ca（Ⅱ）-CS microspheres to cut down the gap between lab and industry.展开更多
We prepared a novel pitch-based activated carbon microsphere（ACM）and studied its in vitro adsorption characteristics for biological molecules.The original spherical asphalt particles were prepared through bitumen em...We prepared a novel pitch-based activated carbon microsphere（ACM）and studied its in vitro adsorption characteristics for biological molecules.The original spherical asphalt particles were prepared through bitumen emulsification.After oxidation and burning,ACMs with a range of parameters were prepared.In vitro adsorption experiments of ACMs for biological molecules were carried out.The prepared ACMs possessed a BET specific surface of 1566 m^2/g with a voidage of 0.653 cm^3/g and a volume of micropores of 0.478 cm^3/g.They showed high adsorption for glucose and creatintine.Compared with the medically used carbon powder,the prepared ACMs exhibited significantly lower adsorption for digestion enzymes.In conclusion,the prepared ACMs,as an oral adsorbent candidate,possessed higher BET specific surface area and larger volume of micropores;they also exhibited favorable selective adsorption features for biological molecules.展开更多
A kind of novel pitch-based activated carbon microsphere（ACM） characterized by its controlled porous structure was developed in this study,the curative effect of this ACM on diabetes mellitus in rats was investigate...A kind of novel pitch-based activated carbon microsphere（ACM） characterized by its controlled porous structure was developed in this study,the curative effect of this ACM on diabetes mellitus in rats was investigated.ACM 0.2-0.3 mm in diameter was prepared by modified method.The optimal ACM was screened by its adsorption ability for glucose.Diabetes mellitus model was established by streptozotocin injection in male Sprague-Dawley rats.Two groups of rats were orally administrated with ACM twice a day for 30 d.Intestinal glucose transport was determined in vitro using everted rat intestinal sacs technique.Compared with the diabetic mellitus group,the ACM treated group showed significant lower blood glucose level and improved glucose tolerance after two-week treatment.If ACM was applied in the mucosal side,glucose permeation clearance in the ACM treated group was significantly higher than that of the control group,especially at high glucose concentration（10 mg/mL） on the serosal side.The selected ACM possessed a BET specific surface of 1566 m^2/g and high volume of micropores（0.478 cm^3/g） with fine spherical morphology,and showed more significant adsorption capacity for glucose.As oral microsphere preparations,ACM presented the curative effect on streptozotocin-induced diabetes mellitus in rats.展开更多
基金Supported by the National Basic Research Program of China (2007CB613507)
文摘The magnetic poly-（methacrylate-divinyl benzene） microspheres with micron size were synthesized by modified suspension polymerization method. Adsorption of Cr（VI） from aqueous solution by magnetic poly-（MA-DVB） microspheres with surface amination was investigated. The adsorption processes were carried out under diversified conditions of pH value, adsorption time and temperature to evaluate the perlbrmance of the magnetic microspheres. The optimum pH value for Cr（VI） adsorption was found as 3. The adsorption capacity increased with adsorption time and attained an optimum at 60 rain. The adsorption processes for magnetic microspheres was endothermic reaction, and the adsorption capacity increased with increasing temperature.
基金Project(GC201204)supported by the Open Fund of Guangdong Provincial Key Laboratory for the Green Chemicals,China
文摘The magnetic gelatin-starch microspheres were prepared by modified emulsion cross-linking method with glutaraldehyde as the cross-linking agent. The structure, size distribution as well as morphology of magnetic microspheres were investigated by FT-IR spectrometer, dynamic laser scattering analyzer and scanning electron microscope, respectively. Bovine serum album(BSA)was chosen as model protein, and the adsorption processes were carried out under diversified conditions including BSA initial concentration, p H value, adsorption time and temperature to evaluate the performance of the magnetic microspheres. The average diameter of optimized spherical magnetic microspheres is 1.6 μm with excellent dispersivity, and the saturation magnetization is found to be equal to 1.056×10-2 A·m2. The adsorption isotherm of the BSA on the magnetic microspheres basically obeys the Langmuir model, with a maximum adsorption capacity of 120 mg/g and an adsorption equilibrium constant of 1.60 mL/mg.
基金Supported by the National Key Basic Research Development Plan(No.2013CB632602)the National Natural Science Foundation of China(No.21306198)
文摘In this study, quaternized chitosan microspheres （QCMS） were prepared and its Cr （VI） removal potential was investigated. Batch experiments were conducted to examine kinetics, adsorption isotherm, pH effect, and thermodynamic parameters. Equilibrium was attained within 50 rain and maximum removal of 97.34% was achieved under the optimum conditions at pH 5. Adsorption data for Cr （VI） uptake by the QCMS were analyzed according to Langmuir, Freundlich, and Temkin adsorption models. The maximum uptake of Cr （VI） was 39.1 mg.g-a. Thermodynamic parameters for the adsorption system were determinated at 293 K, 303 K, 313 K and 323 K. （AH° = 16.08 kJ.mol- 1;AG° = -5.84 to -8.08 kJ.mo1-1 and AS° = 74.81 J.K-1 .tool-l）. So the positive values of both A/-F and AS° suggest an endothermic reaction and increase in randomness at the solid-liquid interface during the adsorption. AG° values obtained were negative indicating a spontaneous adsorp- tion process. The kinetic process was described by a pseudo-second-order rate equation very well. The results of the present study indicated that the QCMS could he considered as a potential adsorbent for Cr （V1） in aqueous solutions.
基金the National Natural Science Foundation of China(2117613621422603)the National Science and Technology Support Program of China(2011BAC06B01)
文摘In this work, an equilibrium-dispersion model was successfully established to describe the breakthrough performance of Ca（Ⅱ） imprinted chitosan （Ca（Ⅱ）-CS） microspheres packed column for metal adsorption, and the assumptions of Langmuir isotherms and axial dispersion controlled mass transfer process were confirmed. The axial dispersion coefficient in Ca（Ⅱ）-CS microspheres packed column was found to be almost proportional to the linear velocity and fit for prediction through single breakthrough test. Sensitivity analysis for breakthrough curve indicated the axial dispersion coefficient as well as Langmuir coefficient was sensitive variable for deep removal requirement. The retrieval of the adsorption isotherms of Ca（Ⅱ）-CS microspheres from breakthrough curve was fulfilled by modelling calibration. A strategy based on the correlation between adsorption isotherms and breakthrough performance was further proposed to simplify the column adsorption design using absorbents with small/uniform size and fast adsorption kinetics like Ca（Ⅱ）-CS microspheres to cut down the gap between lab and industry.
文摘We prepared a novel pitch-based activated carbon microsphere（ACM）and studied its in vitro adsorption characteristics for biological molecules.The original spherical asphalt particles were prepared through bitumen emulsification.After oxidation and burning,ACMs with a range of parameters were prepared.In vitro adsorption experiments of ACMs for biological molecules were carried out.The prepared ACMs possessed a BET specific surface of 1566 m^2/g with a voidage of 0.653 cm^3/g and a volume of micropores of 0.478 cm^3/g.They showed high adsorption for glucose and creatintine.Compared with the medically used carbon powder,the prepared ACMs exhibited significantly lower adsorption for digestion enzymes.In conclusion,the prepared ACMs,as an oral adsorbent candidate,possessed higher BET specific surface area and larger volume of micropores;they also exhibited favorable selective adsorption features for biological molecules.
基金The Ministry of Science and Technology of the People’s Republic of China (Contract No. 2010DFA44300)Shanghai Committee of Science and Technology (Grant No.10DZ2220500 and 11DZ2260600)
文摘A kind of novel pitch-based activated carbon microsphere（ACM） characterized by its controlled porous structure was developed in this study,the curative effect of this ACM on diabetes mellitus in rats was investigated.ACM 0.2-0.3 mm in diameter was prepared by modified method.The optimal ACM was screened by its adsorption ability for glucose.Diabetes mellitus model was established by streptozotocin injection in male Sprague-Dawley rats.Two groups of rats were orally administrated with ACM twice a day for 30 d.Intestinal glucose transport was determined in vitro using everted rat intestinal sacs technique.Compared with the diabetic mellitus group,the ACM treated group showed significant lower blood glucose level and improved glucose tolerance after two-week treatment.If ACM was applied in the mucosal side,glucose permeation clearance in the ACM treated group was significantly higher than that of the control group,especially at high glucose concentration（10 mg/mL） on the serosal side.The selected ACM possessed a BET specific surface of 1566 m^2/g and high volume of micropores（0.478 cm^3/g） with fine spherical morphology,and showed more significant adsorption capacity for glucose.As oral microsphere preparations,ACM presented the curative effect on streptozotocin-induced diabetes mellitus in rats.
