Comparison of Supported Ionic Liquid Membranes and Polymeric Ultrafiltration and Nanofiltration Membranes for Separation of Lignin and Monosaccharides

Abstract

Lignin is one of the three main components of lignocellulosic biomass and must be considered a raw material with attractive applications from an economic and ecological point of view. Therefore, biorefineries must have in mind the most adequate processing to obtain high-quality lignin and the separation tasks that play a key role to improve the purity of the lignin. Separation techniques based on membranes are a promising way to achieve these requirements. In this work, the separation performance of the SILM (Supported Ionic Liquid Membrane) formed with [BMIM] [DBP] as IL (Ionic Liquid) and PTFE as membrane support was compared to a nanofiltration (NF) membrane (NP010 by Microdyn-Nadir) and two ultrafiltration (UF) membranes (UF5 and UF10 by Trisep). The SILM showed selective transport of Kraft lignin, lignosulphonate, xylose, and glucose in aqueous solutions. Although it was stable under different conditions and its performance was improved by the integration of agitation, it was not competitive when compared to NF and UF membranes, although the latter ones suffered fouling. The NF membrane was the best alternative for the separation of lignosulphonates from monosaccharides (separation factors around 75 while SILM attained only values lower than 3), while the UF5 membrane should be selected to separate Kraft lignin and monosaccharides (separation factors around 100 while SILM attained only values below 3).

Separation of Volatile Fatty Acids from Model Anaerobic Effluents Using Various Membrane Technologies

“…Another major difference of SILMs—compared to pressure- and osmotically driven membranes—is that the passage on SILMs depends mainly on polarity (partition coefficients) and much less on molecular size [ 55 ]. This difference in selectivity based on size vs. polarity is clearly shown in the work of Abejón et al, where the selectivity between monosaccharides and macromolecules (lignosulfonates, lignin) are compared for SILM vs. loose NF and tight UF, displaying a difference of almost two orders of magnitude [ 56 ].…”

Ionic liquids membranes for liquid separation: status and challenges

“…146 As for biomass separation, the [BMIM][DBP]-PTFE SILMs were fabricated for the selective transport of Kraft lignin, lignosulphonate, xylose, and glucose in aqueous solutions by Abejón and coworkers. 147,148 Although there are only a few reports of ILMs for these applications at present, further investigation is expected to unlock the potential applications and progress in this area.…”

Application of Poly(Ethyl Eugenyl Oxyacetate) Compounds as the Ions Carrier for Heavy Metals Separation and Separation of Fe and Ni in Ferronickel Using Liquid Membrane Transport Method

“…The concentration of metal ions in the source and stripping phases were analyzed using AAS. The optimum pH was used to optimize the ion carrier volume (7.5, 8.5, and 10 mL), the stripping concentration (0.5, 1, 2, and 4 M), transport time (12,24,36, and 48 h), and metal ion concentration (0.075, 0.1, 0.25, 0.5 mM). Transported efficiency or transport percent is calculated based on Eq.…”

“…Meanwhile, the optimum PEEOA volume for transporting other metal ions is 7.5 mL. The increasing volume of ions carrier will increase flux and permeability on the liquid membrane [11][12]. Hence, complex formation at the membrane interface is accelerated and increased.…”