Lignin Valorization: Concentration of Model Phenolic Compounds by Nanofiltration

Abstract

Lignin is a biopolymer found in plants which can be valorized as a source of value added compounds by breaking its structure in the constituting monomers. A model solution was prepared with seven phenolic compounds, including vanillin and syringaldehyde, usually found after alkaline lignin oxidation. The model solution was concentrated by nanofiltration membranes with low molecular weight cut-off (MWCO). Two membranes (DOW NF270 and KOCH MPS-34) were tested for permeate fluxes and phenolic compound rejection. Significant reduction of the volume mixture was achieved with high permeate fluxes as well as high rejections (above 90%) for the phenolic compounds studied. The membrane with the best performance was the DOW NF270 with maintained high rejections while having higher permeate fluxes resulting in higher productivity when compared with the other membrane KOCH MPS-34 also tested.

Advances and Applications of Hollow Fiber Nanofiltration Membranes: A Review

“…Lignin concentration from synthetic organosolv liquors by NF has been studied and lignin rejection of 99% has been achieved with flat thin film composite membranes, consisting of a polyamide selective layer on a commercial polysulfone support (FilmTec NF270 from Dow) [222]. Gomes et al studied the concentration of synthetic mixture of phenolic compounds by commercial flat-sheet NF membranes (FilmTec NF270 from Dow and MPS-34 from KOCH) [223]. The mixture mimicked the composition of oxidized black liquor, and a significant concentration was achieved with high permeate fluxes and rejections above 90%.…”