The Consistency of Yields and Chemical Composition of HTL Bio-Oils from Lignins Produced by Different Preprocessing Technologies

Author(s)

Halleraker, Hilde Vik ; Kalogiannis, Konstantinos ; Lappas, Angelos ; Castro, Rafael C. A. ; Roberto, Ines C. ; Mussatto, Solange I. ; Barth, Tanja

• Document type: Journal article
• Source: ENERGIES; v. 15, n. 13, p. 21-pg., 2022-07-01.

Abstract

This work evaluates the effect of feedstock type and composition on the conversion of lignin to liquid by solvolysis with formic acid as hydrogen donor (LtL), by analyzing the yields and molecular composition of the liquid products and interpreting them in terms of both the type and the preprocessing of the lignocellulosic biomass using chemometric data analysis. Lignin samples of different types and purities from softwood, hardwood, and grasses (rice straw and corn stover) have been converted to bio-oil, and the molecular composition analyzed and quantified using GC-MS. LtL solvolysis was found to be a robust method for lignin conversion in terms of converting all samples into bio-oils rich in phenolic compounds regardless of the purity of the lignin sample. The bio-oil yields ranged from 24-94 wt.% relative to lignin input and could be modelled well as a function of the elemental composition of the feedstock. On a molecular basis, the softwood-derived bio-oil contained the most guaiacol-derivatives, and syringol was correlated to hardwood. However, the connection between compounds in the bio-oil and lignin origin was less pronounced than the effects of the methods for biomass fractionation, showing that the pretreatment of the biomass dominates both the yield and molecular composition of the bio-oil and must be addressed as a primary concern when utilization of lignin in a biorefinery is planned. (AU)

• FAPESP's process: 15/20510-9 - Techno-economic assessment of ethanol production from rice straw based on the biochemical biorefinery
• Grantee: Rafael Cunha de Assis Castro
• Support Opportunities: Scholarships abroad - Research Internship - Doctorate
• FAPESP's process: 15/24813-6 - Assessment of a biochemical platform based on two streams model (C6 and C5) for conversion of rice straw into ethanol
• Grantee: Ines Conceicao Roberto
• Support Opportunities: Regular Research Grants
• FAPESP's process: 13/13953-6 - Ethanol production from rice straw by simultaneous saccharification and fermentation employing a non-conventional stirred reactor
• Grantee: Rafael Cunha de Assis Castro
• Support Opportunities: Scholarships in Brazil - Doctorate