Renewable biopolyols from residual aqueous phase resulting after lignin precipitation

Abstract

The aim of this work was to obtain two biopolyols from the liquid residue resulting from the precipitation of lignin contained in two different black liquors, Eucalyptus globulus organosolv black liquor (EOBL) and Pinus radiata organosolv black liquor (POBL), thus adding value to this residue. Eucalyptus organosolv polyol (EOP) and Pine organosolv polyol (POP) were characterized to know their viscosity, hydroxyl number (IOH), and functionality according to the corresponding standard American Society for Testing Materials (ASTM). The molecular weight of the biopolyols was measured through gel permeation chromatography (GPC); the chemical structure and composition were characterized by Fourier transform infrared (FTIR) and gas chromatography–mass spectrometry (GC-MS), respectively; and the thermal degradation (TGA) of the two biopolyols was determined. The biopolyols showed suitable properties to be employed in the production of polyurethanes (PU).