Rational design of polymer-based absorbents: application to the fermentation inhibitor furfural

Abstract

BackgroundReducing the amount of water-soluble fermentation inhibitors like furfural is critical for downstream bio-processing steps to biofuels. A theoretical approach for tailoring absorption polymers to reduce these pretreatment contaminants would be useful for optimal bioprocess design.ResultsExperiments were performed to measure aqueous furfural partitioning into polymer resins of 5 bisphenol A diglycidyl ether (epoxy) and polydimethylsiloxane (PDMS). Experimentally measured partitioning of furfural between water and PDMS, the more hydrophobic polymer, showed poor performance, with the logarithm of PDMS-to-water partition coefficient falling between −0.62 and −0.24 (95% confidence). In contrast, the fast setting epoxy was found to effectively partition furfural with the logarithm of the epoxy-to-water partition coefficient falling between 0.41 and 0.81 (95% confidence). Flory-Huggins theory is used to predict the partitioning of furfural into diverse polymer absorbents and is useful for predicting these results.ConclusionWe show that Flory-Huggins theory can be adapted to guide the selection of polymer adsorbents for the separation of low molecular weight organic species from aqueous solutions. This work lays the groundwork for the general design of polymers for the separation of a wide range of inhibitory compounds in biomass pretreatment streams.

Challenges in lipid production from lignocellulosic biomass using Rhodosporidium sp.; A look at the role of lignocellulosic inhibitors

“…These materials are used because of their hydrophobic nature as they can extract non‐polar compounds with low solubility. However, for the adsorption of furfural, it is necessary to use highly polar polymeric species to obtain a better separation of these compounds …”

“…Recently, the development of new technologies for the detoxification of in situ hydrolysates has used methods based on membrane technology, such as nanofiltration, reverse osmosis, and membrane distillation, due to their easy handling and the low amounts of energy they need for their operation . Likewise, another technology in constant development and with a high potential for the removal and recovery of inhibitors is based on the use of hydrophobic resins and chemically modified polymers to obtain a greater specificity towards this type of compound …”

Integrating a Biorefinery into an Operating Kraft Mill

“…Strategies are needed to produce sufficiently refined sugars from wood that are competitive with corn dextrose as a feedstock for fermentation to platform chemicals. Cost-effective removal of inhibitors will be a key part of developing commercial processes for wood sugars (Ajao et al 2015;Mechmech et al 2015;Nwaneshiudu and Schwartz 2015). Simple processes such as over-liming have been effective in detoxifying acid hydrolysates of wood chips for ethanol production (Mendes et al 2011).…”

Cross-Linked Polyethylenimine for Selective Adsorption and Effective Recovery of Lignocellulose-Derived Organic Acids and Aldehydes

“…To date, a variety of methods including extraction, chromatography, and adsorption have been developed to separate the lignocellulose-derived organic acids and aldehydes. − Among them, the adsorption method is particularly attractive because of the low cost and easy operation. Polymeric, carbonaceous, mobile composite material (MCM), and zeolite adsorbents have been widely used to adsorb aldehydes such as furfural and HMF in sugar solutions. − However, carbonaceous adsorbents can undesirably adsorb sugars due to the presence of oxygen groups, which can greatly decrease the hydrophobicity of adsorbent. − Zhang et al found that activated carbon adsorbed fermentation sugars and the adsorption capacity could reach as high as 120 mg·g –1 when it was present during ethanol fermentation .…”