Highly selective adsorption of 5-hydroxymethylfurfural from multicomponent mixture by simple pH controlled in batch and fixed-bed column studies: Competitive isotherms, kinetic and breakthrough curves simulation

Abstract

Fixed-bed column adsorption is one of the most promising technologies for the separation and purification of 5-hydroxymethylfurfural (5-HMF) from biomass hydrolysate from the point of view of industrial application. However, one of the most pressing issues to be resolved is how to improve the separation factor of 5-HMF and its by-product levulinic acid (LA) and formic acid (FA). In this study, we used poly (BDM-alt-DVB) resin (BD-11) as an adsorbent and a simple pH control in batch and fixed-bed column to explore the competitive adsorption behavior and mechanism of 5-HMF from multicomponent solution. Without adjustment for solution pH, the separation factors of α5-HMF/LA, α5-HMF/FA, α5-HMF/Glucose were 2.6, 11.3, and 22.2, respectively. Interestingly, the separation factors of α5-HMF/LA, α5-HMF/FA, α5-HMF/Glucose increased dramatically to 73.0, 72.2, and 49.2 by merely adjusting the solution pH to 7.02. Furthermore, when the pH was adjusted to 7.02, the equilibrium time of 5-HMF adsorption on the BD-11 resin was within 20 min, and the adsorption capacity reached 69.7 mg/g, which was 118 % of the equilibrium adsorption capacity of the unadjusted pH value. In addition, the proposed fixed-bed column multicomponent competitive adsorption model was shown to agree well with the experimental data and successfully simulated the adsorption behavior of 5-HMF under a variety of experimental conditions. In conclusion, the fixed-bed column had great potential in 5-HMF selective adsorption from an aqueous solution by simple pH control.