Lignin Biorefinery: New Horizons in Catalytic Hydrodeoxygenation for the Production of Chemicals

Abstract

Lignin is a byproduct of the paper mill and second-generation (2G) ethanol biorefinery and the largest naturally available source of aromatic building blocks. It can serve as a feedstock to produce bulk, fine, and functionalized aromatic compounds along with aliphatic cyclic alcohols, jet fuel, and aliphatic hydrocarbons. Hydrodeoxygenation (HDO) is one of the promising strategies to produce these compounds from lignin-derived phenolics. Many reactions occur during the HDO; hence, it is very crucial to design active, selective, and long-life catalysts and choose the optimal reaction conditions to synthesize targeted end products. Herein, we first survey the conventional and new lignin fractionation techniques and determine the lignin structure, composition, and bonding with cellulose and hemicellulose. After this, we review the recent advances in the production of alkanes, arenes, cyclic alcohols, jet fuel range hydrocarbons, and HDO of raw lignin bio-oil. This review exclusively discusses the product distribution during HDO based on catalyst composition, solvent, and reaction parameters. Moreover, the review also underlines the selectivity of various catalytic systems to yield specific products such as BTX, important petrochemical materials, aliphatic hydrocarbons, cyclic alcohols, and jet fuel range hydrocarbons.

One-step conversion of lignin-derived alkylphenols to light arenes by co-breaking of C–O and C–C bonds

“…The selectivity for arenes reached the highest value of 84.0% at the temperature of 450 °C. The breaking of the C–O 22,23 and C–C 24 bonds of alkylphenols are both exothermic reactions. It was reasonable that a maximum value of selectivity for arenes appeared with the higher temperature from the perspective of thermodynamics.…”

2021 Pioneers in Energy Research: Javier Bilbao

“…The biodiesel oxidation stability time was drastically improved with lignin-derived additives. A comprehensive review on lignin HDO has been written by Kumar et al, 35 including the following topics: (1) lignin structure depending upon the extraction method, (2) lignin depolymerization (pyrolysis and liquefaction), and (3) HDO of lignin-derived volatiles (ex situ or in situ). Arroyo et al 36 have studied the decarboxylation of different fatty acids (stearic, oleic, and palmitic acids) over Pd/zeolite catalysts to produce hydrocarbons, under various conditions (temperature, H 2 /N 2 , type of zeolite, etc.).…”

“…The biodiesel oxidation stability time was drastically improved with lignin-derived additives. A comprehensive review on lignin HDO has been written by Kumar et al, including the following topics: (1) lignin structure depending upon the extraction method, (2) lignin depolymerization (pyrolysis and liquefaction), and (3) HDO of lignin-derived volatiles ( ex situ or in situ ). Arroyo et al .…”

Rheological Characterization of Mixed Aqueous Solutions of Enzymatic Hydrolysis Lignin and Ionic Liquid

“…[4,5] Lignin has attracted more and more attention due to its increasing use in the production of bulk, fine and functional aromatic compounds, as well as aliphatic cyclic alcohols, aviation fuels and aliphatic hydrocarbons. [6][7][8][9][10] Therefore, it is of great significance to develop an environment-friendly lignin dissolving solvent. [11] Room temperature ionic liquids (ILs), which are considered as ideal green solvents, due totheir advantages such as width of liquid range, excellent dissolution ability, free from the influence of vapor pressure and easy recovery.…”

“…One of the main ways of lignin value is to produce aromatic compounds in chemical industry.Nowadays, due to the importance of lignin in biorefinery, the research on value‐added platform, special chemicals and alternative fuels using lignin has developed rapidly [4,5] . Lignin has attracted more and more attention due to its increasing use in the production of bulk, fine and functional aromatic compounds, as well as aliphatic cyclic alcohols, aviation fuels and aliphatic hydrocarbons [6–10] . Therefore, it is of great significance to develop an environment‐friendly lignin dissolving solvent [11] …”