Potential of nanofiltration and reverse osmosis processes for the recovery of high-concentrated furfural streams

摘要

BACKGROUND Furfural is an interesting compound that can be produced from renewable and sustainable resources and is used in platform chemicals for the synthesis of biofuels and other chemicals. However, a recovery step is required to separate furfural from lignocellulosic hydrolysates when cellulose-based raw materials are used. In this work, nanofiltration (NF) and reverse osmosis (RO) processes have been evaluated to purify or concentrate synthetic furfural solutions. RESULTS Two NF membranes (NF90 and NF270) and three RO membranes (XLE, BW30 and SW30) were evaluated to recover furfural from high-concentrated solutions containing 9 g furfural L-1. Rejection percentages and permeate flux performances were determined and membranes were characterized by X-ray photoelectron spectroscopy (XPS) and scanning electron microscopy (SEM). Results indicated that higher trans-membrane flux could be obtained by NF membranes, being the highest when using NF membranes (260 +/- 14 L m(-2) h(-1)) and the lowest with the BW30 membrane (3.3 +/- 0.7 L m(-2) h(-1)) working at 20 bar. On the other hand, NF270 allowed the passage of furfural (around 84 +/- 3%), while the other tested membranes (NF90, XLE, SW30 and BW30) rejected it (between 67 +/- 2 and 90 +/- 3%). CONCLUSION For this reason, it can be concluded that NF270 will be an option for furfural purification, while NF90 and RO membranes could be used for concentration purposes. (c) 2019 Society of Chemical Industry