Separation of Oleic Acid from Soybean Oil Using Mixed-Bed Resins

Abstract

Two mixed bed ion-exchange resins (Dowex Monosphere MR-450 UPW and Amberlite MB-150) were investigated for their ability to remove oleic acid from a laboratory-prepared 5 % (w/w) oleic acid/soybean oil mixture. The performance of the heterogeneous mixed-bed resins to remove oleic acid from the mixture was investigated for resin loading and reaction duration while the mixing rate, reaction temperature, and initial oleic acid composition of the mixture were kept constant. Both resins removed > 93 % of the oleic acid in the sample within 4 h with a 20 % (w/w) resin loading in a nonpressurized batch reactor system at 50 °C. The maximum adsorption capacity for Amberlite MB-150 and Dowex Monosphere MR-450 UPW was determined to be 0.27 g·g−1 (oleic acid/wet resin) and 0.26 g·g−1 (oleic acid/wet resin), respectively. Ion-exchange of oleic acid onto the quaternary ammonium site of the mixed-bed resin was determined to be the mechanism of oleic acid removal. The presented research has promising application in the areas of refining edible oils and biodiesel production from free fatty acid-containing feed stocks.

FFA Adsorption from Waste Oils or Non-Edible Oils onto an Anion-Exchange Resin as Alternative Method to Esterification Reaction Prior to Transesterification Reaction for Biodiesel Production

“…Therefore, it is likely that the FFA decrease observed by them is due to adsorption of free fatty acids on the resin as demonstrated earlier in our study. Besides, some researchers agree in anion-exchange resin (basic resin) the mechanism of FFA removal appears to be adsorption to the basic site; while in cation-exchange resin (acidic resin), FFA removal is accomplished by the esterification of FFA at the acidic functional site in the presence of methanol or ethanol [44].…”

Adsorption of oleic acid from sunflower oil on Amberlyst A26 (OH)

“…1, the adsorption reached equilibrium after 360 min later for all studied conditions. According to studies presented by Jamal et al [12] and Maddikeri et al [6] the contact time to reach equilibrium for oleic acid adsorption from vegetable oils onto ion exchange resins was found at 240 and 300 min, respectively. Cano et al [11] reported that the adsorption of oleic acid on iron oxide magnetic nanoparticles from ethanol-hexane solution reached equilibrium after 60 min later.…”

“…[6]. Although the adsorption of fatty acids from various solvents such as ethanol [7], benzene [8], isooctane [9] and solvent mixtures [10,11] has been studied by researchers, adsorption of fatty acids from vegetable oils has attracted growing attention in recent years [6,[11][12][13].…”

“…Ion-exchange resins have been also used to remove fatty acids from mixtures which were laboratory prepared by adding fatty acids in refined vegetable oils [6,12]. Maddikeri et al [6] investigated the adsorption characteristics of stearic and oleic acid from sunflower oil using Indion 810, Indion 860 and Indion 850 ion exchange resins.…”

“…Maddikeri et al [6] investigated the adsorption characteristics of stearic and oleic acid from sunflower oil using Indion 810, Indion 860 and Indion 850 ion exchange resins. In another study, Jamal et al [12] studied the adsorption of oleic acid from soybean oil using Dowex monosphere MR-450 and Amberlyst MB-150 ion exchange resins. Apart from the ion exchange resins, Cano et al [11] investigated the adsorption of oleic acid from ethanol-hexane solution and from vegetable (olive and sunflower) oils by using iron oxide magnetic nanoparticles as adsorbent.…”