Extraction, quantification and characterization of lignin extracted from bamboo biomass

Abstract

Lignin, a heterogeneous polymer that presents about 20–30% in lignocellulose emerged as a promising feedstock for the production of specialty chemicals. After cellulose, Lignin is the second most abundant natural polymer. Lignin is a three-dimensional, highly cross-linked macromolecule composed of three types of substituted phenols, which include coniferyl, sinapyl, and p-coumaryl alcohols having a vast number of functional groups and linkages. The properties of lignin are dependent upon the type of extraction method used. This work-study was carried out focusing on the properties of lignin extracted from bamboo (Bambusa Polymorpha) using acid treatment, alkali treatment and sequential organosolv treatment. Isolated lignins were characterized by Fourier transform infrared spectroscopy (FTIR), UV analysis, Thermogravimetric analysis (TGA) to compare thermal and chemical composition. It was found that lignin obtained from organosolv method provided the greatest yield of the various extraction methods. FTIR spectral studies showed the characteristics peaks of lignin and it was found that the bamboo lignin is unique and it is HGS type lignin. The type of extraction method used was seen to affect the thermal properties. It was found that lignin extracted from acid treatment has the greatest thermal stability and purity.