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In the continuity of a previous jet-cooled rovibrational study of trans and cis conformers of 2-furfural in the mid-infrared region (700–1750 cm−1) [Chawananon et al., Molecules 28 (10), 4165 (2023)], the present work investigates the far-infrared spectroscopy of 2-furfural using a long path absorption cell coupled to a high-resolution Fourier transform spectrometer and synchrotron radiation at the AILES beamline of the SOLEIL synchrotron. Guided by anharmonic calculations, vibrational energy levels and excited-state rotational constants are sufficiently predictive for a complete assignment of all fundamental and combination bands up to 700 cm−1, as well as the rovibrational analysis of 4 (1) low-frequency modes of trans-(cis-)2-furfural. A global rovibrational simulation, including far-infrared rovibrational lines and microwave and millimeter-wave rotational lines assigned in a previous study [Motiyenko et al., J. Mol. Spectrosc., 244, 9 (2007)] provides a reliable set of ground- and excited-state rotational parameters involving ring torsion, bending, and ring puckering modes of 2-furfural. In a second step, a rovibrational analysis of several hot band sequences, mainly involving the lowest frequency ring CHO torsion mode, is carried out. Reliable values of some anharmonic coefficients are obtained experimentally and could serve as a benchmark for validating advanced anharmonic calculations related to these large amplitude motions of flexible molecules. [ABSTRACT FROM AUTHOR]

The La nanorod and cobalt-manganese spinel were synthesised by an improved sol–gel technique for the selective oxidation of alcohols. The active sites of the catalyst were demonstrated using parameters and a recycling study. Moreover, the catalyst was characterized by Raman spectroscopy, X-ray photoelectron spectroscopy, Fourier transform infrared spectra, X-ray diffraction, and surface analysis to examine the impact of La addition on the structural and morphological characteristics of CoMn2O4. La is introduced into CoMn2O4, which decreases the activation energy; therefore, CoMn2-XLaXO4 selectively oxidizes alcohol at lower temperatures. Higher benzyl alcohol to benzaldehyde conversion was observed for the CoMn1.96La0.04O4 catalyst. The catalyst was further also examined for the selective oxidation of other alcohols. The various commercially important substrates like 2-bromo benzyl alcohol, furfuryl alcohol, etc. undergo selective oxidation using a catalyst was also been investigated. The mechanistic aspects of the catalyst with active sites have been explained using Raman and ATR-FTIR adsorption study. [ABSTRACT FROM AUTHOR]

In this work, the catalytic conversion of furfural was found to follow both CTHs and etherification pathways in one-pot over multicationic inorganic perovskites (LaNi1-xMoxO3±δ) as heterogeneous catalysts. The conversion of furfural (FA) into alcohols and ether functionalities using the as-synthesized perovskite catalysts showed good conversions that are above 80% and excellent selectivity towards the desired product. The LaMoO3 catalyst was found to achieve the highest percentage conversion of 83%. Simple and multicationic inorganic perovskites were successfully employed in the transformation of furfural to produce β-methoxy-2-furanethanol. Furthermore, we postulate the hydrogenation of the keto-group to be the first step in the mechanism of the formation of β-methoxy-2-furanethanol and that its formation is characterized by rearrangement of the intermediate over the surface of the catalyst. [ABSTRACT FROM AUTHOR]

Metal–organic framework (MOF) catalysts promise selective hydrogenation of C═O bonds, a process that is thermodynamically unfavorable because of the presence of C─O, C═C, and C─C bonds within furan rings. However, the reactivity and stability of MOF are often impeded in catalytic reactions by structural collapse or phase transition stemming from commonly employed strategies such as defect engineering. The present work investigates a novel strategy for designing highly active Co₁Ni₁@UiO‐66‐NH₂ catalysts by embedding Co₁Ni₁ within the UiO‐66‐NH₂ framework. This approach facilitates efficient charge transfer between the reactants and the catalysts, thereby preserving both reactivity and structural integrity. The turnover frequency of Co1Ni1@UiO‐66‐NH2 is 430 h⁻¹, in contrast to 18 h⁻¹ of UiO‐66‐NH2, demonstrating that the transfer hydrogenation activity of Co1Ni1@UiO‐66‐NH2 is 24 times greater than that of UiO‐66‐NH2. More importantly, the reaction rate achieves 7.27 mol g⁻¹ h⁻¹, with a furfuryl alcohol (FOL) yield of 100%, and the Co₁Ni₁@UiO‐66‐NH₂ catalyst retains its excellent catalytic activity even after eight cycles of applications. Density functional theory calculations indicate that, in comparison to UiO‐66‐NH₂, Co‐ and Ni@UiO‐66‐NH₂, Co₁Ni₁@UiO‐66‐NH₂ exhibits relatively strong interactions and significant charge exchanges between reactants and catalysts. These interactions not only facilitate the dehydrogenation of isopropanol but also enhance the hydrogenation of furfural. Furthermore, the density of states reveals a greater number of states near the Fermi level in Co1Ni1@UiO‐66‐NH2 compared to Co‐ and Ni@UiO‐66‐NH2, and thereby facilitates the substantial charge exchanges and efficient catalytic performance of Co1Ni1@UiO‐66‐NH2. [ABSTRACT FROM AUTHOR]

The supercritical water gasification (SCWG) is a convenient and efficient method to utilize hydrogen stored in biomass. Furfural is an important platform during the conversion of biomass thus it is of great significance to understand the microscopic mechanism of the SCWG of furfural. In this work, the SCWG of furfural is investigated using reactive molecular dynamic (RMD) simulations under the temperature range from 1800 K to 2800 K. Based on the detailed reaction scheme of furfural pyrolysis and SCWG, it is found pyrolysis dominates the conversion of furfural under low temperature such as 2400 K and produces only a small amount of H 2 ; while under higher temperature, H 2 O participates in SCWG as reactant and actively reacts with furfural and C3 fragments in forms of H and OH radicals, which promotes the production of H 2. In addition, the combination of water and C3 fragments also effectively inhibits the coke formation. This work could provide a further insight for the conversion of biomass to hydrogen energy at the atomic level. [Display omitted] • Reactive simulations of furfural gasification in supercritical water. • Identification of the decomposition pathways of the pyrolysis and SCWG of furfural. • H and O sources provided by H 2 O promote the full conversion of furfural. • Inhibition of coke deposition through the combination of H 2 O and small fragments. [ABSTRACT FROM AUTHOR]

The demand for renewable energy and chemicals from biomass resources has led to the development of methods for biorefining lignocellulosic materials into pellets and value‐added chemicals. This has, in turn, driven a search for alternative raw materials to use as feedstock in such biorefineries. This study proposes the inclusion of low‐grade lignocellulosic residues from agriculture and forestry, such as straw and woody biomass with a high bark content, in the feedstock mix for steam explosion (STEX) based biorefineries. It focuses on exploring how the use of low‐grade residues affects the yield of value‐added chemicals that arise as side streams during the steam explosion of lignocellulosic biomass and if acetic acid impregnation of the biomass prior to STEX pretreatment will further improve yields of valuable side stream chemicals. The raw materials were impregnated with water/acetic acid before being subjected to STEX pretreatment, using high temperatures (190 °C–223 °C), and a reaction time of 8 min before pressure release. Value‐added chemicals were identified in two separate aqueous side streams. In the condensed process effluents, the most abundant compounds were acetic acid (1.2 g*kg−1 dry input biomass) and furfural (1.4 g*kg−1 dry input biomass), and the highest yields were found in the samples from mixed spruce and branches and tops (BRAT) at high temperatures. Filtrate samples produced from washing the steam‐exploded biomass contained acetic acid (53.6 g*kg−1 dry input biomass), furfural (4.1–7.9 g*kg−1 dry input biomass) and 5‐hydroxymethylfurfural (5‐HMF) (9.0 g*kg−1 dry input biomass) as the most abundant compounds and highest yields of target compounds were found in samples of spruce alone and of spruce mixed with BRAT. All compounds in the side streams were identified and quantified using quantitative 1H nuclear magnetic resonance spectroscopy (qNMR). This study demonstrates that high yields of valuable chemicals are present in the aqueous side streams of pellet production using alternative feedstocks such as forestry and agricultural residues. [ABSTRACT FROM AUTHOR]

Quantum chemical methods have been intensively applied to study the pyrolytic conversion of glucose into hydroxymethylfurfural (HMF) and furfural (FF). Herein, we collect the most relevant mechanistic proposals from the recent literature and organize them into a single reaction network. All the transition structures (TSs) and intermediates are characterized using highly accurate ab initio methods and the possible reaction pathways are assessed in terms of the Gibbs energies of the TSs and intermediates with respect to β‐glucopyranose, selecting a 2D ideal‐gas standard state at 773 K to represent the pyrolysis conditions. Several pathways can lead to the formation of both HMF and FF passing through rate‐determining TSs that have ΔG‡ values of ~49–50 kcal/mol. Both water‐assisted mechanisms and nonspecific environmental effects have a minor impact on the Gibbs energy profiles. We find that the HMF → FF + CH2O fragmentation has a small ΔrxnG value and an accessible ΔG‡ barrier. Our computational results, which are in consonance with the kinetic parameters derived from lumped models, the results of isotopic labeling experiments and the reported HMF/FF molecular ratios, could be useful for modeling studies including on nonequilibrium kinetic effects that may render more information about product yields and the relevance of the various pathways. [ABSTRACT FROM AUTHOR]

This work reports the renewable synthesis of 3-(2-furyl)acrylic acid and its novel-substituted derivatives, with potential applications as sustainable chemical building units, starting from carbohydrate-derived 5-substituted-2-furaldehydes and malonic acid employing various organocatalysts. Piperidinium acetate as the catalyst afforded good to excellent isolated yields of the acrylic acids under solvent-free conditions. The substituted 3-(2-furyl)acrylic acids were esterified using MeSO3H/SiO2 as a heterogeneous acid catalyst. The 3-(2-furyl)acrylic acids containing acid-sensitive functional groups on the furan ring were esterified by dimethyl carbonate as the sustainable reagent by base-catalyzed transesterification reaction. Moreover, the olefinic group was selectively reduced by catalytic hydrogenation using 5%Pd/C as the catalyst. The catalytic processes were optimized on various reaction parameters, and the synthesized compounds were characterized by FTIR, NMR (1H, 13C), and elemental analysis. [ABSTRACT FROM AUTHOR]

Desilication in alkaline medium has been widely used in construction of hierarchical zeolites for industrially relevant catalytic processes. The built of hierarchy in zeolites, especially with low aluminum stability or high Si/Al ratio, often suffers from uncontrolled destruction of zeolitic framework, accompanied by a significant loss of microporous domains and intrinsic acidity after desilication. Here, we report a novel and simple methodology for preparation of hierarchical zeolites with highly complete framework and minimum sacrifice of microporosity and acidity. The pre‐impregnated amines in zeolite micropores act as inner pore‐directing agents (iPDAs), largely protecting the zeolitic framework and moderating the silicon extraction during the alkaline treatment. The resulting hierarchical zeolites exhibit high crystallinity, tunable hierarchy, stable framework, and well‐preserved acidity, endowing them with significantly improved mass transport properties and enhanced activities in catalytic conversion of methanol or furfural. [ABSTRACT FROM AUTHOR]

Layered double hydroxides (LDH) have significant attention in recent times due to their unique characteristic properties, including layered structure, variable compositions, tunable acidity and basicity, memory effect, and their ability to transform into various kinds of catalysts, which make them desirable for various types of catalytic applications, such as electrocatalysis, photocatalysis, and thermocatalysis. In addition, the upcycling of lignocellulose biomass and its derived compounds has emerged as a promising strategy for the synthesis of valuable products and fine chemicals. The current review focuses on recent advancements in LDH‐based catalysts for biomass conversion reactions. Specifically, this review highlights the structural features and advantages of LDH and LDH‐derived catalysts for biomass conversion reactions, followed by a detailed summary of the different synthesis methods and different strategies used to tailor their properties. Subsequently, LDH‐based catalysts for hydrogenation, oxidation, coupling, and isomerization reactions of biomass‐derived molecules are critically summarized in a very detailed manner. The review concludes with a discussion on future research directions in this field which anticipates that further exploration of LDH‐based catalysts and integration of cutting‐edge technologies into biomass conversion reactions hold promise for addressing future energy challenges, potentially leading to a carbon‐neutral or carbon‐positive future. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomasses are promising source of fermentative sugars for the production of succinic acid. The lignocellulosic matrix must be pretreated to make the sugars available for the fermentation, but the most tested operative conditions can generate inhibitors as acetic acid, furans, phenolic compounds. Inhibitors remained an obstacle for the implementation of succinic acid production starting from recalcitrant biomasses as wheat straw. Batch tests were performed at two starting concentrations of strain, sugars (glucose, glucose and xylose) and inhibitors (acetic acid and furfural) by comparing the fermentation in standard broth medium and hydrolysate. Notwithstanding the presence of acetic acid (52.5 mg/L) and furfural (15 mg/L), succinic acid was obtained at 9*10−2 ± 7*10−3 g/L by starting from wheat straw hydrolysate that contained glucose (1.1 g/L), xylose (0.4 g/L) and without additional nitrogen source. Therefore, the study highlighted that a more concentrated inoculum was able to reduce the synergistic effect of inhibitors at their highest concentrations. The results obtained may contribute to improve succinic acid production from the biomasses that have been under-exploited but abundantly available, as wheat straw, for which solutions must be found to solve the problem of inhibitors production or to mitigate its effect on the fermentation process. [Display omitted] • The limited fermentability of straw hydrolysate has still been demonstrated. • Actinobacillus succinogenes produced succinic acid from wheat straw. • Both inhibitors (acetic acid and furfural) reduced succinic acid production. [ABSTRACT FROM AUTHOR]

Electrocatalytic upgradation of biomass for chemicals and energy production is an emerging approach to address the environmental issues related to chemicals and energy production. If coupled with renewable energy, this approach will further enhance the sustainability goals for the future energy and chemical sector. This work critically reviews the progress on oxidative and reductive electrocatalytic upgrading of biomass-derived chemicals such as glycerol, sorbitol, levulinic acid, 5-hydroxymethylfurfural, furfural, and bio-oil to value-added products, including 2.5-dimethyl tetrahydrofuran, 2.5-dihydroxy methyl tetrahydro furan, 2-hydroxymethyl-5-(methyl amino methyl) furan, and 2,5-furan dicarboxylic acid with simulations production of hydrogen (H2) energy. The role of the mediator in electrocatalytic upgradation serves as a high-efficiency catalytic platform for oxidation and reduction reactions. Pd and Ru exhibit promising attributes such as durability and superior electrocatalytic hydrogenation performance. Additionally, this review discusses various methods for enhancing biofuel through a multitude of approaches, such as hydrocracking, hydrotreatment, supercritical fluid processing, steam reforming, catalytic cracking, esterification, emulsification, hydrodeoxygenation, and electrocatalytic hydrogenation. Techno-economic assessment of electrocatalytic conversion of biomass to chemicals and energy are explored to identify the key contributing factors toward the economic viability of electrocatalytic upgradation of biomass for chemical and energy. Finally, research gaps are identified for further work along with economic assessment of electrocatalytic upgradation of biomass technology with and without integration of renewable energy. [ABSTRACT FROM AUTHOR]

Lignocellulosic biomass is considered a sustainable source for the production of biofuels and platform molecules such as furfural (FAL). In this study, a series of solids with different acidity were tested for the production of FAL from xylose and corn residues. Functionalized Cloisite Na+ (CLOI-SO3H) and Preyssler heteropolyacid (HPA-Preyssler) showed the best catalytic performance in the production of FAL form xylose. Under optimal reaction conditions, the HPA-Preyssler catalyst achieved a maximum yield of 75% in just 15 min and maintained its activity for 5 consecutive reaction cycles, while the CLOI-SO3H catalyst obtained a 97% yield in 15 min, but its activity decreased considerably during reuse. Using techniques such as FTIR, SEM, EDS, and TGA, the possible causes of the decrease in the activity of the catalysts were established. The cellulose, hemicellulose, and lignin contents of different corn residues were determined to determine the most appropriate for the production of FAL. Using the HPA-Preyssler, the temperature and amount of catalyst selected for the dehydration of xylose to FAL, the appropriate time, amount of substrate, and type of solvent were established to obtain FAL directly from yellow corn stalks, reaching a maximum yield of 14% concerning hemicellulose content in 3 h at 180 °C in DMSO without performing any pretreatment to the corn residues, and the catalyst was recovered for subsequent reactions. Therefore, using the HPA-Preyssler catalyst is a new alternative for efficiently converting xylose or residual lignocellulosic biomass into FAL. [ABSTRACT FROM AUTHOR]

The development of green route for preparing propylene oxide (PO) with molecular oxygen is of significance both in academic and industrial. In this work, propylene epoxidation coupled with furfural oxidation catalyzed by platinum meso-tetraphenylporphyrin (Pt (II)TPP) has been developed. Propylene conversion and PO selectivity reached up to 56% and 83%, respectively. Meanwhile, furfural was almost completely converted to furoic acid. Based on operando characterizations and electron paramagnetic resonance (EPR) tests, a mechanism involved high-valent Pt species was proposed. This work is expected to provide a potential application prospects for producing PO and furoic acid simultaneously in chemical industry. [ABSTRACT FROM AUTHOR]

The efficient utilization of lignocellulosic hydrolysates in bioprocesses is impeded by their complex composition and the presence of toxic compounds, such as furan aldehydes, formed during lignocellulose pretreatment. Biological detoxification of these furan aldehydes offers a promising solution to enhance the utilization of lignocellulosic hydrolysates. Acinetobacter baylyi ADP1 is known to metabolize furan aldehydes, yet the complete spectrum of reaction products and dynamics remains unclear. Here, we determined the detoxification metabolites of furfural and 5-hydroxymethylfurfural in A. baylyi ADP1 and studied the kinetics of detoxification. The results indicate that detoxification in A. baylyi ADP1 follows a typical alcohol-aldehyde-acid scheme, with furoic acid and 5-hydroxymethyl-2-furancarboxylic acid as the final products for furfural and 5-hydroxymethylfurfural, respectively. Both end products were found to be less toxic for cells than their unmodified forms. These findings underscore the potential of A. baylyi ADP1 in detoxifying lignocellulosic hydrolysates for bioprocess applications. [ABSTRACT FROM AUTHOR]

A series of sulfonated carbon acid catalysts with strong acidity was prepared by simultaneous carbonization and sulfonation of biomass sucrose in the presence of the organic sulfonating agent sulfosalicylic acid under hydrothermal conditions at temperatures ranging from 150 to 200 °C. It was found from FTIR and XPS spectra that the surface of carbon was efficiently functionalized with –SO3H groups. Research on the mechanism of the sulfonation process indicated that the intermediate 5-hydroxymethyl furfural (5-HMF), which was easily hydrolyzed from sucrose, was prone to carbonization and functionalized with –SO3H groups simultaneously. Compared with 5-HMF and fructose used as the initial carbon precursor, the slow hydrolysis of sucrose to intermediate 5-HMF to suppress its rapid carbonization is favorable for the efficient grafting of –SO3H groups when sucrose is used as the initial carbon precursor. The prepared sulfonated carbons were evaluated as acid catalysts in a typical ester hydrolysis reaction, namely, hydrolysis of ethyl acetate. The sulfonic acid groups were identified to be the active sites and quantified by a cation-exchange process. The activity of the sulfonated carbon was primarily correlated with the total number of active sites. However, when the total number of the –SO3H groups did not change, higher activities were shown on the sulfonated carbon with higher surface S content. [ABSTRACT FROM AUTHOR]

Catalytic transfer hydrogenation (CTH) is a safe and effective strategy for producing unsaturated alcohols (UOLs) from biomass‐derived α,β‐unsaturated aldehydes/ketones. Accordingly, the design of CTH catalysts that possess both extreme activity and superior selectivity is highly desirable. Herein, we develop a highly efficient Pt@hMgAl catalyst with Pt nanoparticles (NPs) confined in the layered double hydroxide derived hollow MgAl‐oxide nanospheres (hMgAl), which shows an enhanced catalytic performance in CTH of furfural (FFR) to furfuryl alcohol (FOL) compared to the hMgAl catalyst without Pt NPs inside. It is found that the reaction rate over the Pt@hMgAl (12.8 mmol gcat−1 h−1) is ~26 times higher than that over the hMgAl (0.5 mmol gcat−1 h−1). The excellent catalytic performance of Pt@hMgAl originates from the synergy between Pt‐(Mg−O−Al) interfacial sites, where the acid‐base site of Mg−O−Al activates the C=O bond of FFR, while the nearby Pt site facilitates the dehydrogenation of 2‐propanol. Moreover, the reaction rate over the Pt@hMgAl can further increase to 21.8 mmol gcat−1 h−1 after introducing H2 into the reaction system, where the FOL selectivity is still higher than 99 % due to the synergy of Pt‐(Mg−O−Al) interfacial sites. This work provides a straightforward approach to construct a hollow‐structured catalyst with abundant metal/oxide interfaces, which could significantly enhance the CTH efficiency for α,β‐unsaturated alcohols production. [ABSTRACT FROM AUTHOR]

Photocatalytic CO2 reduction coupled with alcohol oxidation to aldehyde presents a promising strategy for the simultaneous production of fuels and valuable chemicals. The efficiency of the coupled photocatalytic reactions remains low due to poor charge separation, difficulty in CO2 activation, and uncontrolled compatibility between reactions. This work presents S‐bridged covalent triazine framework (SCTF) core‐ZnIn2S4 shell photocatalysts for simultaneous CO2 reduction and selective furfural synthesis at distinct active sites. As evidenced by in situ X‐ray photoelectron spectroscopy and Kelvin probe force microscopy, photogenerated electrons in the composite photocatalysts transfer from the ZnIn2S4 shell to the SCTF core, improving charge separation. Experimental and theoretical results confirm that the presence of pyridine N atoms (Lewis basic sites) in SCTF enhances CO2 adsorption, thereby reducing the energy barrier for *COOH generation and promoting *CO production. Meanwhile, furfuryl alcohol oxidation and deprotonation occur on ZnIn2S4 by consuming photogenerated holes, which in turn benefits the conversion of CO2 to CO. As a result, the optimized SCTF/ZnIn2S4‐0.2 core/shell photocatalyst exhibited a superior CO production yield of 263.5 µmol g−1 and 95% conversion of furfuryl alcohol to aldehyde under simulated sunlight irradiation. [ABSTRACT FROM AUTHOR]

Furfuryl alcohol (FA) is an important chemical and has extensive applications in varied fields. To realize the highly selective hydrogenation of furfural (FF) to produce FA, the key is the preparation of the catalysts with excellent performance. Herein, a very simple wet chemical method is developed for the one-step preparation of PdAg nanosponges (NSs). Specifically, with Pd(OAc) 2 and AgNO 3 as precursors, and ethylene glycol (EG) as both solvent and reducing agent, PdAg NSs can be grown and assembled at mild temperature of 40 °C. Throughout the reaction, no any surfactants and additional reducing agents are applied. The as-prepared PdAg NSs possess 3D self-supported alloy structures, "clean" surface, abundant pores, high specific surface area and rich defects. In the FF hydrogenation reaction at 60 °C under 1.5 MPa H 2 pressure in the mixed solvent of ethanol and water (1 : 4 in volume ratio), the self-supported PdAg-1 NSs (1 : 1 in Pd/Ag molar ratio) exhibit superior catalytic performance than other PdAg NSs, pure Pd sample and commercial Pd/C (10%). With PdAg-1 NSs as catalyst in the absence of support, 100% FF can be converted and the selectivity toward FA is as high as 97.1% at 36.0 h of reaction. After 4 cycles, PdAg-1 NSs still maintain the high catalytic activity in FF hydrogenation and high selectivity toward FA, which may originate from the 3D self-supported structures, high specific surface area, "clean" surface, rich defects and electronic synergistic effect between Pd and Ag. This simple fabrication of PdAg NSs introduces new ideas for the synthesis of other nanostructured bi- and multi-metallic catalysts for highly selective FF hydrogenation to FA and other advanced applications. The defect-rich PdAg nanosponges are one-step synthesized in ethylene glycol at 40 °C without the uses of any surfactants, additional reducing agents and supports, and exhibit highly catalytic activity and selectivity for furfural hydrogenation to produce furfuryl alcohol under mild conditions. [Display omitted] • PdAg nanosponges (NSs) were one-step grown in ethylene glycol at 40 °C. • The synthesis was achieved without any seed, surfactant and additional reductant. • The PdAg NSs have rich defects and self-supported structures. • PdAg NSs has excellent catalytic performance for furfural (FF) hydrogenation. • 100.0% conversion of FF and 97.1% selectivity to furfuryl alcohol can be achieved. [ABSTRACT FROM AUTHOR]

With the continuous increase in food production to support the growing population, ensuring agricultural sustainability using crop‐protecting agents, such as pesticides, is vital. Conventional pesticides pose significant environmental risks, prompting the need for eco‐friendly alternatives. This study reports the synthesis of new amide‐based insecticidal active ingredients from biomass‐derived monomers, specifically furfural and vanillin. The process involves reductive amination followed by carbonylation. The synthesis of the furfural‐based carbamate yield reaches a cumulative 88 %, with catalysts Rh/Al2O3 and La(OTf)3 being recyclable at each stage. Insecticidal activity assessments reveal that the furfural carbamate exhibits competitive performance, achieving an LC50 of 254.22 μg/cm2, compared to 251.25 μg/cm2 for carbofuran. Ecotoxicity predictions indicate significantly lower toxicity levels toward non‐target aquatic and terrestrial species. The importance of the low octanol‐water partition coefficient of the biobased carbamate, attributed to the oxygen heteroatom and electron density of the furan ring, is discussed in detail. Building on these promising results, the synthesis strategy was extended to six other biobased aldehydes, resulting in a diverse portfolio of biomass‐derived carbamates. A techno‐economic analysis reveals a minimum selling price of 11.1 $/kg, only half that of comparable carbamates, demonstrating the economic viability of these new biobased insecticides. [ABSTRACT FROM AUTHOR]

Copper phyllosilicate (CuPS) catalysts were synthesized and evaluated for the catalytic transfer hydrogenation of furfural to γ‐valerolactone (GVL). Various copper loadings (10–30 wt.%) were studied to elucidate the impact of copper species on catalytic performance. Notably, a high dispersion of copper (%DCu ≈ 70%) and a substantial BET surface area (620 m2/g) were achieved, even at the maximum copper loading of 30 wt.%. TR‐XANEs and XPS analyses identified the two geometric structures of Cu2⁺ on the CuPS catalysts; square planar and octahedral alongside Cu⁺/Cu⁰ species were formed upon reduction at temperatures exceeding 200 °C. The reduced 30% CuPS‐R catalyst, enriched in metallic Cu⁰, achieved complete conversion of furfural, but exhibited low GVL selectivity (22%). Conversely, the as‐synthesized 30% CuPS, predominantly composed of Cu2⁺, showed a lower furfural conversion (14%) but higher selectivity for GVL (37%). The physical mixing of 30% CuPS‐R and 30% CuPS in a 50:50 ratio yielded the best catalytic performance, resulting in 100% furfural conversion and 86% GVL selectivity. The findings suggest that metallic Cu⁰ is essential for initiating the conversion of furfural, while Cu2⁺ plays a critical role in GVL formation. An optimal Lewis/Brønsted acidity (L/B) ratio of 5.7 is proposed for the mixed catalysts. The proposed reaction mechanism underscores the complex interplay between different copper species and acid sites, emphasizing the need for optimizing both metal and acid functionalities in catalyst design. [ABSTRACT FROM AUTHOR]

AbstractDuring a 1-year study, organic aerosol indoor air samples were collected from sites in a library in Rio de Janeiro, Brazil. Indoor air is a cause for public concern in Brazil. This study presents an indoor air survey wherein the concentrations of aliphatic hydrocarbons, phthalates, phenyl phosphates, aldehydes, limonene, organic acids, and particulate matter were determined. Acids were estimated to be ranging between 0.01 and 30.26 ng m−3, whereas furfural ranged between 0.5 and 3.6 g m−3. Compounds such as furfural, hexanal, benzaldehyde, and vanillin were only detected indoors. Results showed that total suspended particle concentrations were higher outdoors than indoors. Interestingly, 1, 1, 1-trichloro-2, 2-bischlorophenylethane (DDT), and its derivatives were also present. Pesticides are used in libraries to control paper-degrading pests. Therefore, DDT and other chemicals remain nondegraded and pollute the library rooms. This study demonstrates the relevance of monitoring indoor air quality in libraries and the pollutants that can affect the well-being of occupants. Moreover, indoor air quality monitoring can provide early warning to library managers about the effects of indoor air characteristics on unprotected and/or preserved items. [ABSTRACT FROM AUTHOR]

Developing chromium‐free and non‐noble metal catalysts with high performance for furfural hydrogenation to high‐value product furfural alcohol is desirable but challenging. Herein we develop and prepare nitrogen‐doping carbon confining cobalt‐based catalysts (Co‐N‐C composites) by a simple pyrolysis process of well‐defined ZIF‐67 MOFs modified with different surfactants (i.e., polyethylene‐polypropylene glycol (F127), polyvinyl pyrrolidone (PVP), cetyltrimethylammonium bromide (CTAB) in this work). The in situ formed carbon shell from F127 surfactants inhibits Co agglomeration during pyrolysis of ZIF‐67 at 800 °C, thus affording abundant active CoNx species and metallic Co clusters, which is confirmed by high‐resolution transmission electron microscopy (HR‐TEM) and X‐ray photoelectron spectroscopy (XPS). The rich mesopore structures in Co‐N‐C@F1270.3 benefit mass transfer of reactants. Co‐N‐C@F1270.3 catalyst exhibits superior catalytic performance of a 97.2% furfural conversion with a 92.5% selectivity toward furfural alcohol and good durability during the chemoselective furfural hydrogenation, which is mainly attributed to the unique confinement of the in situ generated carbon shell. The surfactant‐assisted pyrolysis strategy provides an efficient and facile way to prepare efficient non‐noble metal catalysts to replace chromium‐based catalysts for furfural hydrogenation to furfuryl alcohol in the future. [ABSTRACT FROM AUTHOR]

The document titled "Green Chemistry" published by the Royal Society of Chemistry in 2024 showcases cutting-edge research in the field of green chemistry for a sustainable future. The contents include editorial pieces, critical reviews, tutorial reviews, communications, and papers covering various topics such as biomass-derived molecules, clean production, and chemical recycling. The journal aims to advance scientific knowledge and promote environmentally friendly practices in the chemical sciences. [Extracted from the article]

Nitrogenous chemicals are widely used in the synthesis of medicines, fine chemicals, polymers, and agrochemicals. Biomass and its derived molecules are particularly prominent and provide a green and sustainable production route to nitrogenous chemicals because of their substantial reserves, renewability, and environmental friendliness. Great efforts have been made in the catalytic amination of biomass-derived molecules to fabricate nitrogenous chemicals through C–N bond formation. This review summarizes recent progress made in the catalytic amination of biomass-derived molecules including 5-hydroxymethylfurfural (HMF), furfural (FF), levulinic acid (LA), lignin derivatives and α-keto acids based on the strategies of thermocatalysis, electrocatalysis and photocatalysis. Special attention is paid to advanced catalysts, key intermediates, and detailed reaction pathways in different green catalytic systems, and to discussions of the structure–activity relationships and reaction mechanisms. It ends by listing current challenges in the design and synthesis of biomass-derived nitrogenous compounds and proposes perspectives for future research and development. [ABSTRACT FROM AUTHOR]

Oximation of substituted ketofurfuryl alcohols in the presence of hydroxylamine hydrochloride and pyridine in ethanol as solvent led to a new class of spiro derivatives presenting a 7-methylene-1,6-dioxa-2-azaspiro [4.4] nona-2,8-diene skeleton along with, in some cases, the predictable oxime. The structures of such spiro compounds were determined by 2D NMR spectroscopy. The suggested formation of this skeleton involves an in situ oximation/dehydration/SN' cascade reaction. [ABSTRACT FROM AUTHOR]

Furfural is a renewable platform compound that can be derived from lignocellulosic biomass. The highly functionalized molecular structure of furfural enables us to prepare a variety of high value-added chemicals, which will help realize biomass high-value utilization, and alleviate energy and environmental problems. This paper reviews the research progress on furfural production and upgrading to C5 chemicals from the catalyst perspective. The emphasis is placed on summarizing and refining the catalytic mechanism and in-depth analysis of available data. Specifically, the reaction mechanism of furfural production and upgrading is summarized firstly from the perspective of reaction pathways and reaction kinetics. Then, the available data are further processed to evaluate the actual reaction efficiency of different catalytic systems from multiple dimensions. Finally, based on statistical analysis, the challenges and opportunities of furfural-based research are proposed. [ABSTRACT FROM AUTHOR]

Cyclopentanone (CPO) and cyclopentanol (CPL), derived from renewable biomass resource hemicellulose, are considered sustainable chemicals that can substitute fossil‐based products, which could be obtained through the hydrogenation‐rearrangement reaction of furfural (FFA). However, the inevitable condensation reactions of FFA and furfuryl alcohol (FA) in aqueous solutions generate humins and result in carbon loss, limiting the industrial application of this process. Herein, a series of Cu‐based catalysts were synthesized using the reverse co‐precipitation method with various metal promoters and applied in the FFA hydrogenation‐rearrangement reaction. The highest yield of 97.1 % CPO/CPL achieved in a typical reaction condition at 200 °C, 4 MPa, in 20 wt % isopropanol‐water mixed solvent over CuZnZr catalyst and the recyclability test confirmed that the catalyst had excellent stability. Experimental studies and characterizations showed that the enhanced performance could be attributed to the adequate Lewis acid sites, regulated through the synergistic interaction between Cu, Zn, and Zr compounds. The simultaneous introduction of Zn and Zr promotes the Cu reduction, and results in more dispersed Cu0 and Cu+, providing an ample and reliable active site. This study outlines a viable method for the catalyst designing and valorizing biomass into high‐value‐added products. [ABSTRACT FROM AUTHOR]

Steam explosion (STEX) of woody biomass is an efficient pretreatment method in the production of water-resistant wood pellets. The STEX process also generates an aqueous condensate stream containing dissolved organic compounds, with furfural as the most abundant and valuable component. An industrial-scale recovery process for furfural and other organic by-products is therefore in the process of being developed and built. One challenge in the process has turned out to be the formation of solid particulate matter that can clog filters in the process unit. We have analyzed both the solid deposits and the fluids present at different points in the process unit to try to identify the origin of the particles using spectroscopic and chromatographic analysis, elemental analysis, and scanning electron microscopy. The aqueous fluids deriving from condensed steam contain furfural and other small organic molecules, with a separate low-density organic layer occurring at some points. This layer largely consists of wood extractives, typically terpenoids. In addition, a heavy organic phase comprising mostly furfural was found at one sampling point. The particles comprise a black, largely insoluble material with a H/C ratio of 0.88 and an O/C ratio of 0.26 and a very low ash content. IR spectra show a low content of C–H functional groups, and chromatographic analysis supports an interpretation that the particles are dominantly furfural-sourced humin-like polymers with adsorbed or co-polymerized terpenoids. Particle formation has been reproduced in a laboratory setting with conditions similar to those in the full-scale process. [ABSTRACT FROM AUTHOR]

5‐HMF is a potential platform multifaceted molecule for various industrial applications and can be produced from biomass‐based hexose sugars. In the present study, the indigenously prepared catalyst DICAT‐1 (an acronym derived from DBT‐ICT Center for Energy Biosciences Catalyst #1) has been explored for fructose dehydration, using isopropyl alcohol (IPA) as a green and low boiling point (LBP) organic solvent. The exploration of heterogeneous DICAT‐1 adds specific advantages for 5‐HMF synthesis in terms of high yield, conversion, selectivity, catalyst separation, recycle, reuse, and so forth. Different variants of DICAT‐1, such as DICAT‐1A, DICAT‐1B, DICAT‐1C, and DICAT‐1D, having variable surface acidity were tested for fructose dehydration in the presence of IPA. Of the tested variants, DICAT‐1C provides good yield and selectivity of 5‐HMF. Thus, further process optimization study was conducted to obtain maximum yield, conversion, and selectivity using DICAT‐1C. The intensified process provides maximum 78% yield of 5‐HMF with 83% fructose conversion and 94% selectivity. The catalyst recyclability study showed the consistency in 5‐HMF yield, conversion, and selectivity for five consecutive recycle runs. The study of reaction kinetics showed the first‐order kinetics with an activation energy of 13.16 kJ/mole by using DICAT‐1C catalyst. Thus, the use of easily recyclable and robust catalyst provides an efficient route for production of 5‐HMF in presence of green solvent. [ABSTRACT FROM AUTHOR]

This review summarizes recent applications of small organic and inorganic molecules as catalysts or solvents (chemical hands and scissors) in the production of furfural (FA), 5-(hydroxymethyl)furfural (HMF), and 5-(chloromethyl)furfural (CMF). The possible transformation of lignocellulosic biomass into a one-pot configuration and two-step technique based on the preliminary separation of hemicellulose, lignin and cellulose with the subsequent hydrolysis of separated polysaccharides is compared and discussed. Interestingly, these rather simple and cheap molecules are catalytically active and enable a high rate of conversion of polysaccharides into furfural and its derivatives. Usually, elevated pressure and reaction temperatures above 150 °C are necessary for effective hydrolysis and dehydration of in situ formed monosaccharides; nevertheless, ionic liquids or deep eutectic solvents enable a significant decrease in the reaction temperature and performance of the discussed process at ambient pressure. [ABSTRACT FROM AUTHOR]

The development of platform chemicals derived from biomass, in particular, 5‐hydroxymethylfurfural (5‐HMF) and furfural (FUR), is of crucial importance in biorefinery. Over the past decades, metal‐supported nanostructured zeolites, in particular, metal‐supported hierarchically porous zeolites or metal‐encapsulated zeolites, have been extensively elaborated because of their multiple functionalities and superior properties, for example, shape‐selectivity, (hydro)thermal stability, tunable acidity and basicity, redox properties, improved diffusion, and intimacy of multiple active sites. In this review, the effects of such properties of metal‐supported nanostructured zeolites on the enhanced catalytic performances in furanic compound upgrading are discussed. In addition, the recent rational design of metal‐supported nanostructured zeolites is exemplified. Consequently, the ongoing challenges for further developing metal‐supported nanostructured zeolites‐based catalysts and their applications in HMF and FUR upgrading are identified. [ABSTRACT FROM AUTHOR]

In this work, phosphoric acid pretreatment (0.6% H3PO4, 160 °C, 40 min) of eucalyptus residues was performed to recover the hemicellulosic fraction for further conversion to l‐lactic acid by fermentation with Weizmannia coagulans DSM 2314 (formerly Bacillus coagulans). The hemicellulosic hydrolysate was composed of xylosaccharides 24.8 g L–1 (mainly xylose, 20.3 g L–1), acetic acid 7.8 g L–1, furfural 0.7 g L–1, and acid‐soluble lignin (ASL) 2.1 g L–1. It was subsequently purified by using anion exchange or adsorption resins. Different liquor‐to‐resin ratios were evaluated to obtain a high concentration of xylosaccharides in the eluate and thorough removal of components that inhibit lactic fermentation. The best performance was observed when using Amberlite‐XAD‐4 resin at a liquor‐to‐resin ratio of 3:1. An eluted hydrolysate was obtained, preserving 80% of the xylosaccharides and effectively removing almost all furfural, 90% of ASL, and 32% of acetic acid. Subsequently, l‐lactic acid production by W. coagulans DSM 2314 was evaluated using concentrated nondetoxified and detoxified hydrolysate obtained with a vacuum oven. For the nondetoxified hydrolysate, 12 g L–1 of l‐lactic acid was obtained after 48 h showing a yield of 0.56 glactic acid gsugar–1 and a xylose consumption of 62%. The detoxification of the liquor significantly improved the fermentation performance of W. coagulans, resulting in a concentration of 16 g L–1 of lactic acid after 24 h, with a yield of 0.73 glactic acid gsugar–1, and almost complete xylose consumption. [ABSTRACT FROM AUTHOR]

The direct conversion of furfural (FA) from biomass to pentanediols (PeDs), including 1,2-PeD and 1,5-PeD, is important for replacing fossil resources and developing bio-based polyesters from renewable sources. However, achieving high selectivity for the C–O hydrogenation of the furan ring remains a significant challenge. In this study, we synthesized a series of trimetallic CuCoLa catalysts, using a coprecipitation method with various metal ratios. The reduced CuCoLa catalyst with a metal ratio of 1/3/1, exhibited the highest activity for the selective hydrogenolysis of FA to PeDs. Under optimal reaction conditions (160 °C, 4 MPa H2 for 9 h), CuCoLa(1/3/1)-R achieved yields of 21.7% for 1,2-PeD and 50.1% for 1,5-PeD. Furthermore, the catalyst remained stable after five cycles of FA conversion to PeDs. The high selectivity for PeDs is attributed to the synergistic interaction between Cu and Co and the appropriate number of basic surface sites. [ABSTRACT FROM AUTHOR]

The use of electrocatalytic technology to replace traditional harsh thermocatalysis in the process of biomass utilization has undoubtedly been an effective means to achieve green and sustainable development. The use of the environmentally friendly method of synthesizing furoic acid (FA) from the biomass platform compound furfural (FF) by electrooxidation was investigated. The surface of the Ni–Co oxide electrode with a Ni content of 0.48 (Ni0.48Co0.36O0.16) obtained by a simple electrodeposition method was covered by a layer of flower-like porous structure, while NiO, Co2+, and Co3+ coexisted. Moreover, the Ni0.48Co0.36O0.16 electrode exhibited 95.4% FA faraday efficiency and 99.6% selectivity with a substrate concentration of 20 mM at 1.0 V vs. Hg/HgO and 50 °C. In addition, a mechanism for electrooxidation of FF into FA over a Ni–Co oxide electrode was proposed. [ABSTRACT FROM AUTHOR]

Furfural hydrogenation is one of the most important reactions for the transformation of biomass‐derived resources into high value‐added chemicals. To achieve a highly efficient catalytic activity of the reaction, catalysts with a high dispersion of metal nanoparticles (NPs) on solid supports are required. However, the development of highly efficient and stable catalysts is still challenging. Herein, the highly dispersed nickel nanoparticles (Ni NPs) supported on the hierarchical ZSM‐5 nanosheets (Z5‐NS) derived from the hierarchical ZSM‐5 nanosheets@NiAl‐layered double hydroxides (LDHs) composites were successfully fabricated. Remarkably, the fabricated Z5‐NS/Ni catalyst exhibited a high furfural conversion of 85 % with a yield of furfuryl alcohol of 60 %. This work illustrates the fabrication of highly metal dispersed on solid supports with high metal loading, which can enhance the catalytic performances in the hydrogenation of biomass‐derived compounds. [ABSTRACT FROM AUTHOR]

The field of biocatalysis is envisioned as an important contributor to the development of bioprocesses producing molecules that can replace those derived from oil, while maintaining the durability and resistance characteristics offered by petroleum-based materials. In the search for substitutes for petroleum derivatives, the compounds belonging to the furan platform appear among the best known due to their reactivity, as they present a mono- (Furfural) or disubstituted (5-HMF) furan ring in their structure, identifying them among the molecules with the greatest applications in the synthesis of new fuels and polymer precursors. In this context, taking advantage of the metabolic diversity of microorganisms, biocatalytic and fermentative methods for the bioconversion of furans have been explored, proposing processes of lower cost and low environmental impact. This review presents the oxidation and reduction products of furfural and 5-HMF obtained by biological processes, using cells or enzymes. [ABSTRACT FROM AUTHOR]