Showing papers by "Takeshi Kataoka published in 1993"

Adsorption of BSA on QAE‐dextran: Equilibria

Abstract: Equilibrium isotherms for adsorption of bovine serum albumin (BSA) on a strong-base (QAE) dextran-type ion exchanger have been determined experimentally. They were not affected by the initial concentration of BSA but were affected by pH considerably. They were correlated by the Langmuir equation when pH > or = 5.05 and by the Freundlich equation of pH 4.8, which is close to pl approximately 4.8 of BSA. The contribution of ion exchange to adsorption of BSA on the ion exchanger was determined experimentally. The maximum amounts of inorganic anion exchanged for BSA were 1% and 0.4% of the exchange capacity of the ion exchanger at pH 6.9, respectively. Since the effect of the ion exchange on the adsorption appeared small, BSA may be adsorbed mainly by electrostatic attraction when pH > or = 5.05 and by hydrophobic interaction or hydrogen bonding at pH 4.8. When NaCl coexisted in the solution, the shape of the isotherm was similar to the Langmuir isotherm, but it is shifted to the right. When the concentration of NaCl was 0.2 mol/dm(3), BsA was not adsorbed on the resin. When BSA was dissolved in pure water, the saturation capacity of BSA on HPO(4) (2-),-form resin was about 2 times larger than that for adsorption from the solution with buffer (pH 6.9 and 8.79). The saturation capacity for adsorption of BSA in pure water on HPO(4) (2-) + H(2)O(4) (-)-from resin was much smaller than that from the solution with buffer. The isotherms for univalent Cl(-)-and H(2)PO(4) (-)-form resin was peculiar; that is, the amount of BSA adsorbed decreased with increasing the liquid-phase equilibrium concentration of BSA.

Breakthrough Curve for Adsorption of Acid Dye on Crosslinked Chitosan Fiber

Abstract: The recovery of univalent anionic dye by adsorption on cross-linked chitosan fiber, which we have developed, appeared feasible technically. Equilibrium isotherms for adsorption of Acid Orange II (acid dye) on cross-linked chitosan fibers were correlated by B.E.T. equation for finite number of layers at pH=6.9 and were almost rectangular at pH≤4. The saturation capacities of the dye adsorbed on ChF-A and ChF-B at pH≤4 were 2 and 1.6 times larger than activated carbon fiber, respectively. When pH≤4, breakthrough curve was independent of pH of the solution. The experimental breakthrough curves for pH≤4 were correlated well by the analytical solution for rectangular isotherm system.

Influence of the Concentration of Ions in Solution on the Partition Coefficient between Cation Exchange Membrane and Solution

Abstract: Partition coefficients of some cations between cation exchange membrane and solution were measured. The reciprocals of the partition coefficients were plotted against the corresponding: dimensionless concentrations of ions in solution. The relations obtained experimentally for monovalent-monovalent and monovalent-bivalent ions systems were in agreement with the respective theoretical equations. For the monovalent-monovalent exchange the relation was linear. While in the monovalent-bivalent case it was non linear. We proposed an empirically obtained linear relation for the monovalent-bivalent system. Therefore, the dependence of the reciprocal of partition coefficients on the dimensionless concentration of solution can be represented by a linear relation for both systems.

Recovery of Amine and Paints from Electrodeposition Wastewater by Adsorption on H-Form Resin: Cyclic Operation

Abstract: Wastewater of anionic electrodeposition painting process contained diisopropanolamine, unknown three paints, and two solvents. These contents were recovered by the proposed cyclic operation efficiently. The amine and paints were adsorbed well on an H-form resin. They were desorbed by 2 mol/dm3 aqueous NaOH solution almost irreversibly. After the eluant NaOH broke through, the effluent, which contained NaOH, the amine, and paints, was reused as the eluant in the next elution cycle. This increased the peaks of the elution curves of the amine and paints. The intraparticle effective diffusivities of the amine (adsorption cycle) and Na+ (desorption cycle) were constant after third cycle.