Adsorption Of Protein And Heavy Metal Ions On Chitosan Microspheres Carrying Cibacron Blue F3GA

The novel chitosan beads were prepared from chitosan through inverse suspension crosslinking reaction.Affinity dye-ligand,Cibacron Blue F3GA,was covalently coupled with the aminated chitosan beads. Comparing the SEM micrographs,the result showed that the CB-CS microspheres were spherical in shape and about 400μm in diameter.The data of FT-IR spectra indicated that the coupling of Cibacron Blue F3GA was successful.It was evaluated the adsorption characteristic of CB-CS resin for bovine serum albumin(BSA)from equilibrium adsorption,kinetics of adsorption and Thermodynamic adsorption.The effect of time,pH,and original concentrations of NaCl and BSA on the adsorption are inspected. Then,the absorbent was used for disposal of the protein in the actual wastewater.The result showed that equilibrium data fitted very well to the Langmuir model,k_d was 4.83mg·mL^-1(7.21×10^-5mol·L^-1),between 10^-4mol·L^-1and 10^-6mol·L^-1.The academic saturated adsorption capacity of BSA was 172.41mg·g^-1.The dynamical data fitted very well to the pseudo-second-order kinetic model.When the temperature was 298.15K,303.15K or 313.15K,standard Gibb's free energyâ–³G<0,shandard enthalpyâ–³H>0,standard entropyâ–³S>0,which indicated the adsorption of BSA by CB-CS resin was a spontaneous and endothermic process. When pH was 5.0,the adsorption capacity reached to the maximum 154.25mg·g^-1.The adsorption capacity decreased evidently along with increase of NaCl concentration;and increased with elevation of the initial concentration of BSA.The action of disposal of the protein in the actual wastewater of dairy and bean curd mill was visible.In order to develop the application area of the CB-CS resin,it was researched the adsorption capability of heavy metal ions.The adsorption characteristics of CB-CS resin for C_u²⁺,P_b²⁺and C_d²⁺were seperately evaluated from equilibrium adsorption,kinetics of adsorption and Thermodynamic adsorption.The effect of time,pH,and original concentrations of heavy metal ions on the adsorption were inspected.On the other hand,the adsorption character and selectivity of CB-CS resin for mixtures of heavy metal ions were inspected too.The result showed that the isotherms of adsorption of heavy metal ions by CB-CS resin were good consistent with the Langmuir isotherm model,when the original concentrations of heavy metal ions were between 200 mg·L^-1and 500 mg·L^-1.Equilibrium data fitted very well to the DKR model,when the original concentration of heavy metal ions was 100 mg·L^-1.The dynamical data all fitted very well to the pseudo-second- order kinetics model.When the temperature was 298.15K,308.15K or 323.15K, standard Gibb's free energyâ–³G<0,shandard enthalpyâ–³H>0,standard entropyâ–³S>0,which indicated the adsorption of C_u²⁺,P_b²⁺or C_d²⁺by CB-CS resin was a spontaneous and endothermic process.The adsorption capacity increased along with increasing pH(2-6)and the initial concentration of heavy metal ions.The adsorption selectivity of CB-CS resin to heavy metal ions was in the order of P_b²⁺>C_u²⁺>C_d²⁺.The result showed that CB-CS resin can be reused several times with favorable stabilization.