Unlocking the potential of a sleeping giant: lignins as sustainable raw materials for renewable fuels, chemicals and materials
Editorial article to accompany the Green Chemistry themed issue ‘Lignin Chemistry and Valorisation’.
Thermochemical conversion of lignin to functional materials: a review and future directions
The naturally abundant lignin offers a sustainable platform for the synthesis of functional carbon materials which have been widely used in catalysis, energy storage, and pollutant removal.
Thermal properties of lignin in copolymers, blends, and composites: a review
Modulating thermal properties via lignin copolymers, blends, and composites.
Fractionation of lignin from eucalyptus bark using amine-sulfonate functionalized ionic liquids
Amine-sulfonate functionalized ionic liquids not only dissolve industrial lignin materials like kraft lignin and lignosulfonate, but also offer unique selectivity and efficiency in fractionating lignin from eucalyptus bark.
Base-catalysed cleavage of lignin β-O-4 model compounds in dimethyl carbonate
Dimethyl carbonate (DMC) was used as solvent and non-toxic capping agent in a base-catalysed selective cleavage of lignin model compounds.
Mechanistic investigation of the Zn/Pd/C catalyzed cleavage and hydrodeoxygenation of lignin
While current biorefinery processes use lignin only for its heat value, the conversion of lignin to high value chemicals is an area of increasing interest.
Hydrolytic liquefaction of hydrolysis lignin for the preparation of bio-based rigid polyurethane foam
Hydrolysis lignin (HL) was liquefied employing 50/50 (v/v) water–ethanol mixture for the preparation of bio-based polyols/rigid polyurethane foams.
Reductive deconstruction of organosolv lignin catalyzed by zeolite supported nickel nanoparticles
Breaking good: In situ ATR-IR spectroscopy tracked the Ni catalyzed deconstruction and hydrodeoxygenation of organosolv lignin in n-hexadecane, towards the production of naphthenes.
Path to plastics composed of ligninsulphonates (lignosulfonates)
In tensile behaviour, polymeric materials containing only methylated ball-milled lignin surpass polystyrene, while 85% w/w ligninsulphonate blends approach polyethylene.
Lignin isolation from spruce wood with low concentration aqueous alkali at high temperature and pressure: influence of hot-water pre-extraction
Lignin was successfully isolated from spruce wood with an accelerated solvent extractor using low concentration aqueous NaOH as an extraction solvent. The biorefinery concept was also applied.
Influence of bio-based solvents on the catalytic reductive fractionation of birch wood
In the reductive catalytic fractionation of lignocellulose, the choice of solvent significantly impacts the delignification efficiency, carbohydrate retention in the pulp and the macrostructure of the pulp.
Structural changes in lignins isolated using an acidic ionic liquid water mixture
Recently, acidic ionic liquid water mixtures based on the hydrogen sulfate anion have been shown to effectively extract lignin from lignocellulosic biomass.
Efficient catalytic hydrotreatment of Kraft lignin to alkylphenolics using supported NiW and NiMo catalysts in supercritical methanol
Efficient catalytic hydrotreatment of Kraft lignin to yield aromatic monomers was demonstrated in supercritical methanol using a variety of NiW and NiMo catalysts on acidic, basic and neutral supports.
Oxidative conversion of lignin and lignin model compounds catalyzed by CeO2-supported Pd nanoparticles
Pd/CeO2 efficiently catalyzes the oxidative conversion of 2-phenoxy-1-phenylethanol, a lignin model compound with a β-O-4 linkage, in methanol, producing monomeric aromatics.
Iron-catalysed oxidative cleavage of lignin and β-O-4 lignin model compounds with peroxides in DMSO
Simple FeCl3-derived iron catalysts are used for the cleavage of lignin and β-O-4 lignin model compounds.
Solvent free depolymerization of Kraft lignin to alkyl-phenolics using supported NiMo and CoMo catalysts
The catalytic hydrotreatment of Kraft lignin using sulfided NiMo and CoMo catalysts on different acidic and basic supports (Al2O3, ZSM-5, activated carbon (AC) and MgO-La2O3) was studied in the absence of a solvent.
The synthesis and analysis of advanced lignin model polymers
Advanced lignin model polymers have been synthesised to aid in the development of new methods for lignin valorisation.
Reversible crosslinking of lignin via the furan–maleimide Diels–Alder reaction
Lignoboost lignin was independently functionalized with furan and maleimide groups. Taken together, these functionalized lignins show all the features of reversible networks.
Exploring glutathione lyases as biocatalysts: paving the way for enzymatic lignin depolymerization and future stereoselective applications
One pot – two enzymes. The combination of β-etherases with glutathione lyases enables the selective cleavage of lignin model compounds. Protein engineering of glutathione lyases allows modification of activity and stereoselectivity.
Biocatalytic conversion of lignin to aromatic dicarboxylic acids in Rhodococcus jostii RHA1 by re-routing aromatic degradation pathways
A gene insertion approach is used in Rhodococcus jostii RHA1 to generate pyridine-dicarboxylic acid bioproducts from lignin.
Selective oxidative C–C bond cleavage of a lignin model compound in the presence of acetic acid with a vanadium catalyst
The solvent has great effects on vanadium-catalyzed oxidative C–C bond cleavage of 2-phenoxy-1-phenylethanol with molecular oxygen.
Ethanol as capping agent and formaldehyde scavenger for efficient depolymerization of lignin to aromatics
High monomer yield (60–86 wt%) with little char formation is possible from lignin. Ethanol acts as capping agent of aromatics, as formaldehyde scavenger and hydrogen source, prevent repolymerization.
Towards lignin consolidated bioprocessing: simultaneous lignin depolymerization and product generation by bacteria
Lignin Consolidated Bioprocessing utilizes microbes that simultaneously depolymerize lignin and convert the resulting aromatic compounds to fuel and chemical precursors.
About this collection
Efficient production of biobased chemicals, materials and fuels requires the valorisation of lignin, a biopolymer that comprises up to one-third of the composition and one-fourth of the energy content of lignocellulose. The structural complexity and general recalcitrance of this aromatic biopolymer pose considerable challenges to the elucidation and modification of its structure in addition to its valorisation to green products.
Recently, the scientific community has made significant progress in engineering lignin, characterising its structural features, valorising the biopolymer through catalysis, and finding new outlets for the lignin-derived products.
This themed issue highlights the many aspects of lignin research, the advances made in valorisation and the potential of this abundant and critically important feed component of future biorefineries. The guest editors for this themed issue are Professor Bert Weckhuysen (Utrecht University, Netherlands), Dr Pieter Bruijnincx (Utrecht University, Netherlands), and Dr Roberto Rinaldi (Imperial College London, UK).