Extraction and characterization of lignin from waste invasive weeds with dioxane-based process

This study has put forth the concept of "control through utilization" for invasive weeds, which cause severe damage to ecosystem and biodiversity. The study comprised of extraction of lignin and pretreatment of spent biomass of four invasive weeds. Lignin was extracted from native biomass using 1,4-dioxane as solvent. Lignin yield of all biomass varied in the range 8.61 - 11.14% w/w with the solvent recovery of 75.56-78.88% v/v. Extracted lignin was characterized using FTIR, TGA, and GPC. Lignin from Mikania micrantha had the highest thermal stability (T-50% = 490 degrees C) and molecular weight (M-w = 5537 g/mol). The spent biomass was subjected to dilute acid pretreatment for synthesis of total reducing sugars (TRS). TRS yields from different entities were as follows: non-extracted biomass = 94.18 - 221.81 mg/g, warm water wash = 8.74 - 15.66 mg/g, and raw biomass = 115.9 - 391.27 mg/g raw biomass. Biomass of Saccharum spontaneum gave the highest TRS yield.