Transformation of Symphytum officinale L. and Panicum virgatum L. biomass to 5-Hydroxymethylfurfural for biofuel production

Abstract

Lignocellulosic biomass has the potential to offer a cleaner alternative as a renewable source for fuel production. The present work aimed to use two plants, Symphytum officinale L. (common comfrey) and Panicum virgatum L. (switchgrass) to produce 5-hydroxymethylfurfural (HMF) using metal chloride catalysis in two ionic liquids, 1-butyl-3-methylimidazolium chloride ([BMIM]Cl) or 1-ethyl-3-methylimidazolium chloride ([EMIM]Cl). Pre-treatments were used to increase sugar availability, and two types of treatments were found to be suitable for HMF production. First, the 0.5 M sulfuric acid hydrolysis yielded 230±23 mg of sugars per g of hydrolysed comfrey, and 425±13 mg of sugars per g of hydrolysed switchgrass. Second, the methanol extraction yielded 300±60 mg of sugars per g of extracted comfrey, and 202±16 mg of sugars per g of extracted switchgrass. The yield of HMF produced was improved from <1% using untreated biomass, to 6.04% and 18.0% using methanol extracts of comfrey and switchgrass, respectively.