Adsorption separation of raffinose from sucrose by activated carbon: Equilibrium, kinetics and dynamic breakthrough

Abstract

Separation of oligosaccharides with a varied number of monosaccharides is an important issue in the food chemistry. Raffinose, a functional oligosaccharide, has attracted increasing attentions due to its strong proliferative effect on bacteria. Industrially, cottonseed meal is an important resource for producing raffinose; however, raffinose extracted from the cottonseed meal contains a significant amount of sucrose that debases the raffinose's quality. In this work, an adsorptive separation of raffinose and sucrose on activated carbon was reported. Adsorption isotherms, adsorption kinetics, and dynamic column adsorption-desorption were investigated. The activated carbon chosen has a significantly higher adsorption capacity of raffinose (0.60~0.65 g/g) than sucrose (0.35~0.40 g/g) at the equilibrium concentration studied (~35 g/L) and temperature from Downloaded by [University of Leeds] at 21:22 04 June 2016A c c e p t e d M a n u s c r i p t 2 293 K to 333 K. Adsorption isotherms and kinetics were fitted by Freundlich isotherm model and pseudo-second-order model, respectively. The effect of flow-rate and initial feed concentration on the dynamic adsorption were investigated, meanwhile, the separation performance was further confirmed from the dynamic desorption using aqueous ethanol of 20% as eluant. Remarkably, raffinose with purity over 90% and recovery of 79.2% could be obtained by adsorption-desorption cycle using the aqueous feed solution containing 20 g/L of raffinose and 6 g/L of sucrose.

Prebiotic Potential of Oligosaccharides: In Vitro Study of Indonesian Local Honey from Apis spp. and Trigona spp. Bees

“…is belong to Meliponini (Family of Apidae) are also called "stingless bees' '. Meliponini is closely related to the honey bees, Apini, both belong to the family of Apidae [21]. Trigona spp.…”

“…Beside, it is a high availability adsorbent, which is widely used and affordable. Bao et al [21] showed that the adsorption power of activated carbon on raffinose (0.60~0.65 g/g) was higher than that on sucrose (0.35~0.40 g/g). Raffinose is an oligosaccharide compound.…”

Microwave-Assisted Preparation of Activated Carbon Modified by Zinc Chloride as a Packing Material for Column Separation of Saccharides

“…The application of a column packed with AC has been applied in the manufacture of fructose syrup. 13 The intricate pores of AC provide a long enough route for the saccharide separation; meanwhile, the surface functional groups contribute to the formation of diverse affinities between AC and different saccharides. 14 Besides pore structure and surface functional groups, another concern for AC column separation is the flow velocity.…”