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The utilization of biomass for the production of agricultural green inputs is regarded as a crucial strategy for achieving low-carbon development in agriculture, while also fully harnessing the potential of renewable resources. Pesticides, as a vital agricultural input, often encounter issues pertaining to inefficient usage, resulting in significant environmental pollution and economic losses. As a main component of lignocellulosic biomass, lignin has become one of the most appealing biopolymers for the construction of advanced pesticide delivery systems. This review aims to provide a thorough summary of the advancements in lignin-based controlled release formulations (LCRFs) for the precise delivery of pesticides. The research in this field has experienced rapid growth in the past five years, making it an important area of study. Common LCRFs are introduced, and the factors influencing the release of active ingredients (AIs) within different LCRFs are analyzed. Special emphasis is placed on intelligent-responsive LCRFs, encompassing an overview of the existing formulations and an exploration of their potential application scenarios and development strategies. It is crucial to promote innovation in pesticide formulations based on the actual demands of agricultural production. We hope this review will stimulate the high-value utilization of lignin and the green development of plant protection technologies. [ABSTRACT FROM AUTHOR]

Lignin, an underutilized component of lignocellulosic biomass, is regarded as a rich reservoir for the production of aromatic chemicals and fuels. Despite extensive research in recent years, lignin's potential is far from being fully unlocked. Photocatalysis that uses sustainable solar energy to drive lignin conversion under mild conditions has been identified as a promising strategy and received growing research interest. This review aims to present a critical introduction to the photocatalytic conversion of lignin, including a summary of lignin conversion pathways and mechanisms, as well as the latest cutting‐edge innovations on photocatalyst design and reactor construction. Moreover, the screening of solvents and regulation of other key factors that are involved in photocatalytic lignin conversion are also elucidated and future perspectives and challenges for photocatalytic conversion of lignin into valuable products are discussed. [ABSTRACT FROM AUTHOR]

[Display omitted] • Fluid shear as a novel force was effective in driving biomass pretreatment reactions. • 90% of lignin and hemicellulose in biomass could be separated by fluid shearing. • Glucose yield via enzymatic hydrolysis tripled after fluid-shear pretreatment. • The obtained lignin kept a structure similar to that of native lignin. • Mechanism of biomass pretreatment by fluid shearing was preliminarily revealed. Pretreatment is the initial stage of lignocellulosic biorefinery process, but is limited by the time-consuming processes, harsh conditions and/or undesirable products. Herein, a mild (<60 °C) and highly efficient pretreatment strategy is developed. The novel mechanocatalytical reaction system driven by fluid shear force helps to exfoliate cellulose from lignocellulose, and the heat generated by the shear process can be used to precipitate and recover the dissolved cellulose from the precooled NaOH/urea solution. The regenerated cellulose shows satisfying crystal structure (cellulose II), significantly decreased crystallinity and nearly tripled enzymolysis glucose yield. Almost 90% of lignin and hemicellulose could be rapidly separated. The separated lignin shows a nearly native structure with 64% β-O-4 linkage, which is even higher than the ball-milling lignin (60%). This research provides a theoretical guidance for the mild pretreatment of lignocellulosic biomass, which will push the application of mechanocatalytical reaction system in biorefinery processes on a large scale. [ABSTRACT FROM AUTHOR]

In pursuit of low-carbon development, the production of diverse functional materials from renewable resources, especially lignocellulosic biomass, is of vital importance. Lignin is a major component of lignocellulose, and it is nature's only true high-volume aromatic polymer, which has the advantages of biodegradability, biocompatibility, and low acquisition cost. After modification by a variety of physicochemical strategies, it can be applied as an alternative to basic industrial materials, including polyurethanes, phenolic, and epoxy resins, which stands comparably to conventional synthetic polymers in terms of both performance and reduced cost. To further unlock the potential of lignin, an alluring opportunity is the exploitation of lignin for high-value materials, especially nanomaterials, that find extensive applications in energy and environment areas. This review provides a systematic summary and perspective of research that has been devoted to lignin transformation to high-value materials, ranging from industrially well-established engineering materials to the recently emerged nanomaterials that were used for energy and environment applications. Latest cutting-edge innovations on lignin modification, controlled depolymerization, and assembly during the last five years are summarized. Structure-function relationships of lignin materials in terms of their specific applications are analyzed. Furthermore, challenges and future opportunities for lignin conversion to high-value materials are also provided. We wish this review will stimulate further advances in lignin based high-value materials, and promote "waste" into "wealth". • Lignin-based materials are the way of high-value utilization of biomass. • The development of lignin chemistry is reviewed in this paper. • The modification methods of lignin are summarized. • The application of lignin-based polymer materials is evaluated. • Lignin-based nanomaterials and lithium battery materials are summarized. [ABSTRACT FROM AUTHOR]

The development of a highly active and robust catalyst for the conversion of lignin, the largest volume of renewable aromatic resource in nature, to value-added aromatics is of great importance in sustainable chemistry. However, the condensation of lignin depolymerization intermediates into recalcitrant macromolecules restricts high yields of desired products, and this remains a great challenge in lignin valorization. Here, a serious of bifunctional Ru–ZnO/SBA-15 catalysts were synthesized for lignin conversion to aromatics. Roles of Ru and ZnO in these catalysts for lignin conversion were in-depth analyzed. The effect of the ratio of Ru to ZnO was studied. Other reaction conditions including temperature and time were systematically optimized. More than 51.3% yields of aromatics were obtained over Ru–10ZnO/SBA-15 at 240 °C for 4 h. Structure-activity relationship research of the catalyst revealed that the high yield of product could be attributed to the following three reasons: 1) the Lewis acidic sites on Ru/SBA-15 are significantly improved after ZnO modification, and thus promotes the C–O bond cleavage; 2) the oxophilic ZnO is beneficial to absorb the substrate and reaction intermediates, and therefore enhances the hydrodeoxygenation activity of the adjacent Ru; 3). The interaction between Zn and Ru in Ru–ZnO/SBA-15 changes Ru electronic properties and leads to the formation of highly active catalytic sites with high electron density. These results indicated that the bifunctional Ru–ZnO/SBA-15 catalyst with high catalytic activity could be a good choice for lignin conversion to high-yield aromatics. [Display omitted] [ABSTRACT FROM AUTHOR]

[Display omitted] • Pd NPs are highly dispersed on defective Al-metal organic framework via a facile method. • Missing linker defects produce coordinatively unsaturated metal sites (CUMSs) as catalytic sites. • Defects enhance the catalyst acidity and improve catalytic activity. • Defect engineering of MOFs opens up novel opportunities for lignin valorization. • DFT calculations revealed that the HDO of vanillin underwent a cascade of hydrogenation-hydrogenolysis routes. Designing highly active catalysts for selective hydrodeoxygenation (HDO) of lignin-derived oxygenates into well-defined compounds is of great importance for realizing high-value utilization of lignin. Defect engineering in metal–organic frameworks (MOFs) is an emerging concept for tailoring MOF properties, which might be a promising strategy in the synthesis of high-performance catalysts. Herein, we developed a facile synthetic strategy by adding trifluoroacetic acid as the modulator to prepare a bifunctional catalyst (Pd/NH 2 -MIL-53-d) consisting of Pd nanoparticles highly dispersed on defective NH 2 -MIL-53(Al). Characterizations, including TEM, XRD, IR, XPS and NH 3 -TPD, were employed to reveal the morphology and physicochemical properties of the catalysts. Results indicated that the introduction of defects leads to the generation of coordinatively unsaturated metal sites, which can act as anchor points for high-dispersion of Pd nanoparticles and as additional active acid sites for catalytic reactions. 100% conversion of vanillin and other 8 representative derivates of lignin into their decarbonyl products with yields over 99% has been achieved under mild conditions in the water. Density functional theory calculations revealed that the HDO of vanillin into 2-methoxy-4-methylphenol mainly underwent a cascade of hydrogenation-hydrogenolysis routes, and the synergistic interaction between Pd and defective NH 2 -MIL-53(Al) facilitated the novel bifunctional catalyst to exhibit outstanding catalytic performance. No apparent deactivation of the catalyst was noticed after it was reused 5 times. Therefore, engineering of defects in MOFs holds enormous potential in designing novel bifunctional catalysts for lignin valorization. [ABSTRACT FROM AUTHOR]

[Display omitted] • Mild pretreatments for near-complete saccharification of desirable lignocelluloses. • Integrated green-like biomass pretreatments to achieve maximum cellulosic ethanol. • Green-like pretreatments selectable for generation of nanomaterials and nanocarbon. • Distinct pretreatment mechanisms accounting for biomass recalcitrance reduction. • A novel strategy for cost-effective biofuels and functional materials at high value. Lignocellulose represents the most abundant carbon-capturing substance that is convertible for biofuels and bioproduction. Although biomass pretreatments have been broadly applied to reduce lignocellulose recalcitrance for enhanced enzymatic saccharification, they mostly require strong conditions with potential secondary waste release. By classifying all major types of pretreatments that have been recently conducted with different sources of lignocellulose substrates, this study sorted out their distinct roles for wall polymer extraction and destruction, leading to the optimal pretreatments evaluated for cost-effective biomass enzymatic saccharification to maximize biofuel production. Notably, all undigestible lignocellulose residues are also aimed for effective conversion into value-added bioproduction. Meanwhile, desired pretreatments were proposed for the generation of highly-valuable nanomaterials such as cellulose nanocrystals, lignin nanoparticles, functional wood, carbon dots, porous and graphitic nanocarbons. Therefore, this article has proposed a novel strategy that integrates cost-effective and green-like pretreatments with desirable lignocellulose substrates for a full lignocellulose utilization with zero-biomass-waste liberation. [ABSTRACT FROM AUTHOR]

The selection of a suitable catalytic system for ligninOX reductive depolymerization, with a careful consideration of the reaction conditions and catalyst compositions, is crucial to successful implementation of the oxidation–reduction strategy for lignin conversion. • 43% yields of aromatics were obtained from ligninOX, while only 11% were from lignin. • High hydrogen pressure is not beneficial to the conversion of ligninOX. • Catalysts with high hydrogenation activities tend to reconvert ligninOX to lignin. • LigninOX conversion pathways under different conditions were determined. Recently, a two-step strategy involving oxidative activation and reductive depolymerization becomes very popular for lignin conversion. However, both positive and negative results are obtained, and the detailed mechanism is still unknown. This study thoroughly investigated the effects of several key factors, including hydrogen pressure, reaction temperature, and catalyst compositions, on the reductive conversion of oxidized lignin (ligninOX) to aromatics. For lignin oxidative activation, FT-IR, 2D NMR, and TG/DTG were used to prove that hydroxyl groups at lignin side chains had been successfully oxidized to carbonyl groups by AcNH-TEMPO/HNO 3 /HCl system. For ligninOX reductive conversion, pathways and mechanisms were explored, and the applicable conditions of this strategy were determined. Under relative moderate hydrogen pressure (e.g. 2 Mpa) over metal–acid catalysts, e.g. Ru/γ-Al 2 O 3 combined with Hf(OTf) 4), an obvious advantage of ligninOX conversion was found. Yield of valuable product from ligninOX was 42.98% which was much higher than that (10.99%) from unoxidized lignin. While, under high hydrogen pressure or promoted by catalysts with high hydrogenation activities, ligninOX tended to be reconverted to original lignin structures with loss of its conversion advantage. 2-phenoxyacetophenone as a ligninOX model was used to verify this speculation and to predict reaction pathways over different catalytic systems. These results proved that a catalyst with both hydrogenolysis and hydrolysis activity was essential for efficient ligninOX depolymerization. [ABSTRACT FROM AUTHOR]

The catalytic conversion of lignocellulosic biomass to aviation fuel is identified as a key strategy to alleviate high operating costs and serious environmental pollution caused by using petroleum-derived fuels. Aviation fuel with stringent end-use requirements consists of several specific hydrocarbon compositions, and the conversion of lignocellulose to aviation fuel is more challenging than that to other fuels. In this study, the latest cutting-edge innovations on the catalytic conversion of lignocellulose to aviation fuel was summarized. Promising routes for the catalytic conversion of cellulose, hemicellulose, lignin, and their derivatives were elaborated, with emphasis on those catalytic approaches including depolymerization of C–O bonds, formation/rearrangement of C–C bonds, and hydrodeoxygenation (HDO) removal of oxygen-containing functional groups. Innovations on reaction mechanism exploration, catalyst development, solvent screening, and reaction condition optimization were introduced. It revealed that a 100% biomass-derived aviation fuel could be produced by catalytic methods with the full utilization of all lignocellulosic compositions. Straight and branched paraffins in aviation-fuel range could be generated from cellulose and hemicellulose via various intermediates including 5-hydroxymethylfurfural (HMF), furfural, levulinic acid, and γ−valerolactone. The degradation and HDO conversion of lignin could yield aromatics and cycloparaffins in aviation range. The development of hydrothermal stable catalysts for the controllable formation of C–C bonds among platform chemicals from carbohydrates as well as for the efficient HDO conversion of fuel precursors is particularly important. Image 1 • All compositions in lignocellulose can be catalytically converted to aviation fuel. • A 100% biomass-derived aviation fuel can be produced by catalytic methods. • Paraffins for aviation fuel can be produced from cellulose and hemicellulose. • Cycloalkanes and aromatics for aviation fuel can be generated from lignin. [ABSTRACT FROM AUTHOR]