Adsorption differences and mechanism of chitooligosaccharides with specific degree of polymerization on macroporous resins with different functional groups

Ion exchange resins are promising materials for separating chitooligosaccharides (COSs) with different degrees of polymerization (DP). The adsorbent functional groups significantly determine the interactions with COSs and affect their adsorption and separation efficiency. This study investigated the adsorption behaviors of COSs on macroporous cation exchange resins with different functional groups to clarify the functional group effect on the adsorption of COSs with different DP, which can also help to provide a theoretical basis for the selection of separation medium and optimization of the separation technics of COSs. The results showed that the adsorption of COSs on sulfonic-acid type resin DX-10 and carboxylic-acid type resin DC-10 were favorable, and the adsorption isotherms were in accord with the Sips model. Adsorption thermodynamics showed that temperature had opposite effects on the two resins' equilibrium adsorption capacity of COSs. The diffusion coefficient of COSs on DX-10 resin was greater, and the affinity gap between COSs on DX-10 resin was larger than that of DC-10 resin, which is beneficial for improving the separation resolution of COSs. In contrast, the interaction energy between COSs with high DP and DC-10 resin was weaker compared with DX-10, which made the elution of COSs with high DP easier.(c) 2022 The Korean Society of Industrial and Engineering Chemistry. Published by Elsevier B.V. All rights reserved.

Automated summary

Ion exchange resins have been investigated as a potential material for separating chitooligosaccharides (COSs) with different degrees of polymerization. The functional groups of the resin significantly affect the adsorption behavior of COSs. This study focused on the adsorption behaviors of COSs on macroporous cation exchange resins with different functional groups, providing insights into the functional group effect on the adsorption of COSs with different degrees of polymerization.