β-Factor Based Separation Characteristics of Bio-derived Chemicals Present in Lignocellulosic Hydrolysates Using Vacuum Distillation

Abstract

A chief shortcoming in the bioconversion of lignocellulosic feedstock is the immanent formation of byproducts such as organic acids, furans, and phenols during the pretreatment process, and these byproducts restrict subsequent microbial fermentation and spent stream disposal. Thus, a green and alternative technique for simultaneous removal and recovery of inhibitors is indispensable. This study explored the separation characteristics of organic acids (acetic acid and formic acid), and furans (furfural and 5-hydroxymethylfurfural) present in simulated and crude lignocellulosic acid-hydrolysates using vacuum distillation. The operation parameters selected for distillation experiments were low temperature (333.15 K) and subatmospheric pressure (13.7 ± 1.3 KPa). A modified separation factor β was introduced in a microlevel model to specify the separation characteristics. Furfural had the highest separation factor (value = 1), whereas acetic acid and formic acid had separation factors in the ranges of 0.17 to ...