H. Yoshida et al., ADSORPTION OF GLUTAMIC-ACID ON POLYAMINATED HIGHLY POROUS CHITOSAN - EQUILIBRIA, Industrial & engineering chemistry research, 34(1), 1995, pp. 347-355
Adsorption of L-glutamic acid on the polyaminated highly porous chitos
an (PEI-CH) appeared technically feasible. The saturation capacity for
adsorption of L-glutamic acid was about 1.43 times larger than a comm
ercial weakly basic ion exchanger DIAION WA30. The experimental equili
brium isotherm (q(A)-C-TA curve) for adsorption of L-glutamic acid on
PEI-CH was independent of the initial concentration of L-glutamic acid
but depended on pH of the solution significantly. It appeared that th
e adsorption of L-glutamic acid was controlled by the acid/ base neutr
alization reaction between neutral L-glutamic acid (zwitterion, A(+/-)
) and the weakly basic ion exchanger. The significant effect of pH on
the q(A)-C-TA curve disappeared in the q(A)-C-A+/- curve. Theoretical
equations for equilibrium isotherms for adsorption of L-glutamic acid
on PEI-CH were derived by assuming neutralization reaction between the
carboxylic group of the neutral L-glutamic acid and each three differ
ent fixed amino groups of PEI-CH, The theoretical equations correlated
the experimental equilibrium isotherms well.