Comparison of adsorption equilibrium of fructose, glucose and sucrose on potassium gel-type and macroporous sodium ion-exchange resins.
Adsorption equilibrium of fructose, glucose and sucrose was evaluated on sulfonated poly(styrene-co-divinylbenzene) cation-exchange resins. Two types of resins were used: potassium (K+) gel-type and sodium (Na+) macroporous resins. Influence of the cation and effect of the resin structure on adsorption were studied. The adsorption isotherms were determined by the static method in batch mode for mono-component and multi-component sugar mixtures, at 25 and 40 degrees C, in a range of concentrations between 5 and 250 g L(-1). All adsorption isotherms were fitted by a linear model in this range of concentrations. Sugars were adsorbed in both resins by the following order: fructose > glucose > sucrose. Sucrose was more adsorbed in the Na+ macroporous resin, glucose was identically adsorbed, and fructose was more adsorbed in the K+ gel-type resin. Data obtained from the adsorption of multi-component mixtures as compared to the mono-component ones showed a competitive effect on the adsorption at 25 degrees C, and a synergetic effect at 40 degrees C. The temperature increase conducted to a decrease on the adsorption capacity for mono-component sugar mixtures, and to an increase for the multi-component mixtures. Based on the selectivity results, K+ gel-type resin seems to be the best choice for the separation of fructose, glucose and sucrose, at 25 degrees C.
Nobre
C
C
IBB-Institute for Biotechnology and Bioengineering, Centre of Biological Engineering, University of Minho, Campus de Gualtar, 4710-057 Braga, Portugal. clarissenobre@deb.uminho.pt
Santos
M J
MJ
Dominguez
A
A
Torres
D
D
Rocha
O
O
Peres
A M
AM
Rocha
I
I
Ferreira
E C
EC
Teixeira
J A
JA
Rodrigues
L R
LR
D000327:Adsorption; D000837:Anion Exchange Resins / Q000737:chemistry*; D005632:Fructose / Q000737:chemistry*; D005782:Gels / Q000737:chemistry*; D005947:Glucose / Q000737:chemistry*; D011137:Polystyrenes / Q000737:chemistry; D011188:Potassium / Q000737:chemistry*; D012964:Sodium / Q000737:chemistry*; D013395:Sucrose / Q000737:chemistry*; D013696:Temperature
D000837:Anion Exchange Resins; D005782:Gels; D011137:Polystyrenes; C432006:divinylbenzene-polystyrene copolymer; D005632:Fructose; D013395:Sucrose; D012964:Sodium; D005947:Glucose; D011188:Potassium