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

Abstract

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. © 2019 Society of Chemical Industry

Integration of Nanofiltration and Reverse Osmosis Technologies in Polyphenols Recovery Schemes from Winery and Olive Mill Wastes by Aqueous-Based Processing

“…The NF270 membrane showed higher Jv values for olive pomace extracts when compared with the NF90 and Duracid membranes for the lees filters extracts. NF270 had the highest MWCO (400 Da), followed by NF90 (MWCO 200 Da), and Duracid (MWCO 150–200) [ 56 ]. Nunes et al [ 8 ] compared the NF270 and NF90 membranes with olive pomace aqueous extracts with an effective filtration area of 52 cm 2 and obtained higher permeate fluxes with the NF270 membrane due to the lower hydraulic resistance to water transport by the relatively loose semi-aromatic active layer.…”

“…The membranes’ effectiveness was determined by different parameters. The TMP was calculated by Equation (1) [ 56 ]: where P in is the feed stream pressure (bar), P out is the concentrate stream pressure (bar), and P p is the permeate stream pressure (bar).…”

“…The trans-membrane flux ( Jv ) was also calculated by Equation (2) [ 56 ]: where Q p is the permeate flow (L h −1 ) and A m is the active filtration area (0.014 m 2 ).…”

“…Moreover, the rejection ( R ) percentage was estimated by Equation (3) [ 56 ]: where C f is the feed polyphenol concentration (mg L −1 ) and C p is the permeate polyphenol concentration (mg L −1 ).…”