Sorption Kinetics, Thermodynamics and Regeneration for Lipid Feedstock Deacidification Using a Mixed‐Bed Ion‐Exchange Resin

Abstract

This research investigated adsorptive deacidification of lipid feedstocks using Dowex monosphere MR-450 UPW mixed-bed resin (Sigma-Aldrich, St. Louis, MO). The impact of temperature, mixing and feedstock moisture content on deacidification kinetics is reported. Resin reusability and deacidification of multiple feedstocks was examined. Our results demonstrated that deacidification using the resin followed Lagergren's pseudo first-order reaction kinetics with a rate constant of 1.352/min under the most favorable reaction conditions (50C, 0% moisture content and 550 rpm mixing rate). Gibb's free energy of the reaction increased from −2.81 kJ/mol at 298 K to −12.17 kJ/mol at 323 K, demonstrating the impact of temperature on deacidification. Resin regeneration with methanolbased rinses resulted in at least 40% feedstock deacidification after three wash cycles. Collectively, our research results demonstrate the promise of using heterogeneous gel-type resins for deacidification of a wide range of feedstocks and edible oils with a high percentage of free fatty acid and/or impurities. PRACTICAL APPLICATIONSDowex monosphere MR-450 UPW mixed-bed gelular ion-exchange resin is effectively used for adsorptive deacidification of high fatty acid oils in the absence of alcohol at low reaction temperatures (<60C). The ion-exchange resin surfaces are regenerated with solvent washing and reused for deacidification over multiple cycles.

Equilibrium, Kinetic, and Thermodynamic Studies for Crude Structured-Lipid Deacidification Using Strong-Base Anion Exchange Resin

“…The results from the thermodynamics study are consistent with those reported by Jamal et al, who found that the physicochemical character of the Dowex monosphere MR-450 UPW resin employed in the adsorption of oleic acid from soybean oil resulted in a spontaneous and endothermic process, with positive entropy change. Similar behavior for FFAs adsorption on LSD-263 resin was also found by Du et al However, Maddiker et al observed completely the opposite behavior on physicochemical character, which may have been related to the type of adsorbent and the corresponding interactions between the FFAs and its active sites …”

Equilibrium, Kinetics, and Thermodynamics of Soybean Oil Deacidification Using a Strong Anion Exchange Resin

“…The use of ion exchange resins containing basic sites for the deacidification of fatty systems has already been investigated in the literature and has recently attracted a great deal of attention. − Amberlyst A26 OH resin is suitable for the adsorption of carboxylic acids for various purposes ,− and for the removal of FFAs in fixed beds from different mixtures of vegetable oils with solvents − and in batch containing only acidified oil as the liquid phase . However, in these studies with Amberlyst A26 OH resin, no equilibrium, kinetic, or thermodynamic data were reported on the removal of linoleic acid from soybean oil, an oil of great economic importance.…”

A novel, effective, and feasible method for deacidifying kiwifruit wine by weakly basic ion exchange resins

“…Lagergren's pseudo‐first‐order sorption kinetic model (Lagergren, ), Ho's pseudo‐second‐order sorption kinetic model (Ho & McKay, ) and Weber's particles internal diffusion model (Weber & Morris, ) were used to estimate the deacidification performance of the four resins (Jamal, Luo, Kuo, Rabie, & Boulanger, ).…”