Search Results (186)

Furfuryl alcohol (FFA), a methanol-soluble and highly specific compound for singlet oxygen (¹O₂), was used as a ¹O₂ trapping agent to reevaluate physical and chemical ¹O₂ quenching efficiency of five antioxidants, namely α-tocopherol, butylated hydroxyanisole (BHA), tert-butylhydroquinone (TBHQ), epigallocatechin gallate (EGCG), and quercetin. The total ¹O₂ quenching rate constants of α-tocopherol, BHA, TBHQ, EGCG, and quercetin were 2.0 (±0.1) × 10⁹, 1.1 (±0.1) × 10⁸, 5.6 (±0.3) × 10⁸, 4.1 (±0.1) × 10⁸, and 2.2 (±0.1) × 10⁸ M⁻¹s⁻¹, respectively. The chemical quenching rate constants of α-tocopherol, BHA, TBHQ, EGCG, and quercetin were 1.4 × 10⁷, 2.0 × 10⁶, 7.7 × 10⁶, 2.0 × 10⁷, and 7.9 × 10⁶ M⁻¹s⁻¹, respectively. The percentages of chemical quenching in total ¹O₂ quenching were 0.7%, 1.8%, 1.4%, 4.8%, and 3.6% for α-tocopherol, BHA, TBHQ, EGCG, and quercetin, respectively, indicating that the five antioxidants quenched ¹O₂ almost exclusively by a physical quenching mechanism. This is the first report on the ¹O₂ quenching mechanism of quercetin in methanol solvent. The results of this study will provide theoretical guidance for the application of antioxidants to inhibit edible oil or fat-containing food from photooxidation. Full article

The limited availability of high-quality timber and the increasing demand for wood-based panels have encouraged the exploration of alternative and sustainable lignocellulosic resources. Rattan waste is abundant in Indonesia; however, its low mechanical strength and limited durability restrict its direct application in composite materials. This study investigated the effect of furfuryl alcohol (FA) modification and different adhesive systems on the performance of rattan-based particleboard. Rattan particles were immersed in FA for 24 h and used to produce particleboards (300 × 300 × 10 mm) bonded with phenol formaldehyde (PF), melamine formaldehyde (MF), and urea formaldehyde (UF) adhesives at a resin content of 12%. The boards were manufactured under controlled hot pressing conditions and conditioned for 14 days prior to testing. Furfurylation significantly improved dimensional stability by reducing moisture content, water absorption, thickness swelling, and leaching, with anti-swelling efficiency values ranging from 43.25% to 71.06%. Some selected mechanical properties, including internal bonding strength, hardness, and screw holding power, were also enhanced. However, the modification showed limited influence on the modulus of elasticity and, in some cases, reduced the modulus of rupture. Among the adhesive systems, MF-bonded boards exhibited the most balanced mechanical performance. Furfurylation also produced darker and more uniform board surfaces. These findings indicate that furfurylated rattan particleboards are suitable for non-structural and decorative applications. Full article

Jiaomian base baijiu is an important seasoning liquor used in the blending of sauce-flavor baijiu, yet the mechanism underlying its flavor formation remains insufficiently understood. Moreover, the specific contribution of high-temperature Daqu (HTDQ) to the flavor profile of Jiaomian base baijiu has not been clearly defined. Therefore, this study compared the aroma profiles and flavor compounds of Jiaomian and Chuntian base baijiu. Jiaomian base baijiu displayed stronger Qu-aroma and floral–fruity notes, with six differential flavor markers (VIP > 1) identified, including ethyl acetate, acetaldehyde, and n-propanol. Further analysis showed that yellow HTDQ exhibited greater inner–outer heterogeneity in aroma and flavor profiles than white and black HTDQ. It also contained the highest concentration of flavor compounds and exerted the strongest influence on the flavor of Jiaomian base baijiu. By comparing the flavor compounds of HTDQ and base baijiu, 14 key compounds were identified that mediate the influence of HTDQ on the flavor of Jiaomian base baijiu. These compounds were primarily formed during the early to middle stages of HTDQ fermentation. Correlation analysis further indicated that microorganisms during HTDQ fermentation were predominantly positively correlated with the key flavor compounds. Among them, Thermoactinomyces, Byssochlamys, Kazachstania, Leiothecium, and Trichothecium showed the closest associations—positively correlated with compounds such as 1-nonanol and furfuryl alcohol, and negatively correlated with isovaleric acid. Finally, KEGG enrichment analysis of the flavor compounds suggested that Beta Oxidation of Very Long-Chain Fatty Acids, Mitochondrial Beta-Oxidation of Short-Chain Saturated Fatty Acids, and Fatty Acid Biosynthesis are key pathways involved in the formation of these flavor substances. In summary, this study clarifies the key flavor compounds through which different HTDQ types influence base baijiu flavor, reveals the microbial origins and metabolic pathways of these key flavor compounds, and provides a theoretical basis for regulating HTDQ production and improving the quality of base baijiu. Full article

Research on tannin-based foams has shown promising results. However, all developments in this field have not been addressed from different perspectives, in a systematic way, and with an emphasis on sustainability. This work discusses different formulations, emphasizing their bio-based components and how modifications influence key properties. It examines life cycle assessment (LCA) studies through a sustainability lens and identifies major commercial phenolic products to highlight the practical use of tannin foams for thermal insulation. The type of tannins, as well as their sources, influences the key properties of these foams. The replacement of formaldehyde, a crosslinking agent known for its health risks, is possible, particularly through more sustainable alternatives that allow for foams with better properties than those obtained with formaldehyde. Substitution of diethyl ether with less hazardous alternatives results in foams with improved thermal and mechanical performance. The elimination of the blowing agent—the green alternative—also leads to foams with good performance. The presence of additives (surfactants, plasticizers, and fillers), some of which are sustainable, improves the mechanical properties of the foams. The performance in fire-related applications, already promising, is also enhanced by the presence of additives. An increase in understanding, combined with the sustainable nature of the various alternatives, makes tannin-based foams promising candidates for next-generation insulation and structural materials in construction. Full article

Apple aroma is an important factor influencing consumers’ preferences. To understand the overall flavor characteristics of apples (Ruixue, Liangzhi, Grystal Fuji, and Guifei), volatile compounds and aroma profiles were investigated by headspace–gas chromatography–ion mobility spectrometry (HS-GC-IMS) combined with stir bar sorptive extraction (SBSE) and gas chromatography–mass spectrometry (GC-MS). The results showed that a total of 56 aroma compounds were identified by SBSE-GC-MS, and 39 aroma-active compounds were screened out using aroma intensity (AI) and odor activity value (OAV). Aroma recombination experiments showed enhanced ‘fruity’ and ‘sweet’ notes, whereas ‘floral’, ‘woody’, and ‘green’ aromas were weaker compared to the Crystal Fuji sample. Additionally, GC-IMS coupled with principal component analysis (PCA) was used to distinguish the apple samples, and partial least squares regression (PLSR) was applied to explore the correlation between sensory attributes and characteristic aroma compounds. The results indicated that Crystal Fuji exhibited the greatest correlation with the “woody” attribute, and Ruixue was highly correlated with “fruity”, “green”, and “sour” attributes, while butanoic acid, β-damascenone, butyl acetate, pentyl acetate, furfuryl alcohol, γ-decalactone, and vanillin had a significant impact on the “flower” and “sweet” attributes of Guifei. This study clarified the characteristic aroma composition of the four apple cultivars, providing data support for apple flavor quality evaluation and cultivar optimization. Full article

Efficient conversion of biomass-based platform molecules into high-value derivatives is recognized as one formidable challenge in biomass upgrading. In this work, a one-pot deep eutectic solvents-assisted solvothermal method was developed for the modification of the commercial Pt/C catalysts by introducing a secondary metal (M = Sn, Bi, Ge, Sb, Pb). The structural and electronic properties of the catalysts were precisely tuned. Among the screened metals, the addition of Sn yielded the most significant improvement in catalytic activity. The optimized PtSn_0.5/C-140 catalyst achieved superior furfural (FAL) conversion and furfuryl alcohol (FOL) selectivity under mild conditions (20 °C, 2 MPa H₂). Comprehensive characterizations, including XRD, HRTEM, XPS, and H₂-TPD, confirmed the formation of Pt-Sn solid-solution phase. Furthermore, Characterization and reaction results revealed that the electronic and geometric effects induced by Sn modulated Pt active sites, significantly enhancing the adsorption of the active H species. Additionally, the SnO_x species adjacent to the Pt-Sn sites served as hydrogen spillover acceptors, further accelerating the hydrogenation process. The synergy between the Pt-Sn solid-solution phase and SnO_x species is identified as the origin of the superior performance at room temperature. These findings provide a new strategy for the design of high-performance biomass conversion catalysts by upgrading commercial noble metal catalysts. Full article

Furfural (FAL), an important biomass-derived platform molecule, plays a vital role in bridging biorefineries and the production of high-value chemicals through its selective hydrogenation to furfuryl alcohol (FOL). In this work, a series of Cu-based bimetallic catalysts (Cu₅Ni_x/SiO₂) were prepared by a simple impregnation method and exhibited outstanding catalytic performance for the hydrogenation of furfural under the mild conditions. When the loading of Ni was 2 wt%, the optimal catalytic activity was obtained at 150 °C and 1 MPa H₂, achieving a furfural conversion of 97.3%. This catalyst also showed excellent stability, maintaining high activity and selectivity toward FOL after five consecutive reaction cycles. Structural characterizations using X-ray diffraction (XRD), Hydrogen temperature-programmed reduction (H₂-TPR), Fourier transform infrared spectroscopy (FT-IR), and X-ray photoelectron spectroscopy (XPS) revealed strong electronic interactions between Cu and Ni species. The introduction of Ni promoted the reduction of Ni²⁺ and improved the dispersion of Cu, which in turn increased the number of accessible active sites and facilitated the hydrogenation process. This synergistic effect between Cu and Ni provides an efficient and low-cost strategy for the selective hydrogenation of biomass-derived furfural to high-valued chemicals. Full article

Cyclopentadiene is an important intermediate that is widely used in the production of useful chemicals, high-density aviation fuels and polymers. Conventional technologies for the production of cyclopentadiene from fossil energies suffer from low yield and selectivity. Therefore, the selective production of cyclopentadiene from renewable biomass is highly expected. In this work, a series of metal phosphates were found to be effective solid acid catalysts for the selective synthesis of cyclopentadiene from the dehydration of 1,3-cyclopentanediol, a platform compound that can be obtained from the aqueous phase rearrangement of furfuryl alcohol followed by hydrogenation. Among the investigated catalysts, lanthanum phosphate (LaP) exhibited the best performance. Over it, 100% 1,3-cyclopentanediol conversion and higher than 90% carbon yield of cyclopentadiene were achieved at 473 K under atmospheric pressure. Based on the results of characterization, the excellent performance of LaP catalyst can be rationalized by its higher amount of acid sites and average pore size. Full article

The catalytic synthesis of 1,2-pentanediol from biomass-derived feedstocks is of remarkable significance for addressing current environmental challenges and energy crises. In this paper, a series of Pt-based catalysts were prepared and evaluated in the hydrogenolysis of furfuryl alcohol. The 5Pt0.5Y/MgO provided a 1,2-pentanediol yield of 68.9% and a tetrahydrofurfuryl alcohol yield of 19.8% with 98.1% conversion of furfuryl alcohol, at 200 °C and 2 MPa H₂ for 10 h. The promotional effect of yttrium on the catalytic performance was investigated through catalytic reaction and comprehensive characterization. It was found that the reducibility of Pt species was suppressed by the introduction of Y species, resulting in reduced activity compared to the 5Pt/MgO catalyst. However, the addition of Y notably shifted the reaction pathway towards 1,2-pentanediol formation at the expense of tetrahydrofurfuryl alcohol selectivity. This increase in 1,2-pentanediol selectivity was attributed to a higher concentration of medium-strength basic sites on the Y-modified Pt catalyst. Furthermore, the strong interaction between Y₂O₃, Pt particles, and the MgO support led to high Pt dispersion and stability on the MgO surface, consequently yielding satisfactory recyclability. Full article

With the rapid industrialization, excessive reliance on fossil fuels has resulted in energy crises and environmental pollution, driving the search for sustainable alternatives. Biomass-derived resources have emerged as promising candidates to replace fossil-based feedstocks. Among these, furfural (FF) serves as a key platform molecule that can be catalytically hydrogenated to various high-value chemicals, with furfuryl alcohol (FA) representing one of the most valuable products. Currently, Cr-based catalysts remain predominant for the selective hydrogenation of FF to FA. However, the severe environmental toxicity of Cr necessitates urgent development of alternative Cr-free catalytic systems. This study systematically reviews recent advances in FF hydrogenation to FA, providing an in-depth discussion of reaction mechanisms, including adsorption configurations, solvent effects, and side reactions, as well as a comprehensive analysis of structure–activity relationships, involving active metal, support, promoter, and preparation methods. Furthermore, we evaluate the application of the advanced characterization techniques for monitoring the reaction processes. Finally, we propose the future research directions: (1) designing efficient and stable non-noble metal catalysts and (2) elucidating reaction mechanisms via the combined in situ characterization and theoretical calculations. These efforts would facilitate the academic understanding and industrial implementation of the FF-to-FA conversion process. Full article

Wood modification using biopolymers has emerged as a sustainable alternative to conventional chemical treatments, enhancing wood’s durability, moisture resistance, and mechanical properties while reducing environmental impact. This review provides a comprehensive overview of the latest advancements in biopolymer-based wood modification, focusing on commonly used biopolymers such as furfuryl alcohol, polylactic acid, caprolactone, polybutylene adipate terephthalate, polybutylene succinate, zein, lignin, tannin, chitosan, alginate, gums, fatty acids, rosin, and sorbitol + citric acid. Future perspectives highlight the need for interdisciplinary collaboration between academia, research institutions, and industry to accelerate innovation and commercialization. This review aims to provide valuable insights for researchers and industry professionals working toward the development of high-performance, eco-friendly modified wood products. Full article

The growing need for sustainable and resource-efficient materials increasingly promotes the use of block-glued laminated timber (glulam) in buildings and civil structures such as bridges. While timber is renewable and sustainable, the formaldehyde-based adhesives commonly used in glulam raise environmental and health concerns. This study addresses this gap by presenting one of the first combined life cycle assessment (LCA) and life cycle cost (LCC) analyses of bio-based versus synthetic adhesives for block-glued glulam. A pedestrian bridge in Zwolle, the Netherlands, serves as a case study. Three synthetic adhesives—melamine-urea formaldehyde (MUF), phenol resorcinol formaldehyde (PRF), and phenol formaldehyde (PF)—and two bio-based alternatives—lignin phenol glyoxal (LPG) and tannin-furfuryl alcohol formaldehyde (TFF)—are analyzed. The LCA covers raw material sourcing, transport, and end-of-life scenarios, with impacts assessed in accordance with EN 15804+A2 using Earthster and the Ecoinvent v3.11 database. The proposed method integrates environmental and economic assessments, with results presented both per kilogram of adhesive and per cubic meter of glulam to ensure comparability. Results show that synthetic adhesives have higher environmental impacts than bio-based adhesives: the carbon footprint of 1 kg of adhesive averages 0.60 kg CO₂-eq for bio-based adhesives and 2.01 kg CO₂-eq for synthetic adhesives. LCC are similar across adhesives, averaging EUR 400 per m³ of glulam. These findings suggest that bio-based adhesives can compete environmentally and economically, but their limited availability and uncertain long-term performance remain barriers. Overall, the study highlights trade-offs between sustainability and structural reliability and provides guidance for sustainable adhesive selection in timber engineering. Full article

The aim of the work was to develop a highly effective catalyst for the conversion of furfural into furfuryl alcohol through catalytic transfer hydrogenation, which is an important process for converting biomass-derived compounds into valuable chemicals. A highly mesoporous silica was modified with various zirconium and aluminium precursors to obtain Lewis acid centres. The materials were characterised by nitrogen adsorption, FTIR spectroscopy, pyridine adsorption, thermogravimetry, SEM and XRD. The catalytic properties of the materials versus acid site concentration, alcohol type, zirconium content and reaction time were investigated in a batch reactor. The zirconium propoxide-modified materials appeared to be the most active and selective catalysts in the reaction studied. They showed complete furfural conversion with ca. 99% selectivity of furfuryl alcohol, which was attributed to the predominantly Lewis acidic character of these catalysts. High productivity, 15.2 mol_FA/mol_Zr·h, was obtained for the most active catalyst. Good catalytic stability was confirmed in repeated cycles. The oxide form of zirconium and aluminium species resulted in the mixed Lewis and Brönsted acidity, which encouraged further transformation of furfuryl alcohol into butyl furfuryl ether, angelica lactone and butyl levulinate. The elaborated catalyst offers a promising approach for converting renewable resources into industrially relevant chemicals. Full article

This study aimed at defining the infrared spectral signatures of volatile organic compounds (VOCs) of relevant interest for coffee bean authentication and quality control. Fourier Transform Infrared Spectroscopy was employed to acquire the mid-infrared absorption spectra of some representative coffee markers, namely Pyridine, 2-Methylpyrazine, 2,5-Dimethylpyrazine, Furfural, 5-Methylfurfural and Furfuryl Alcohol, with high resolution of 0.1 cm⁻¹. Mixtures of these VOCs simulating their amount in coffee seeds were analyzed using multilinear regression. The achieved results demonstrate the potentiality of coffee fingerprinting by VOC’s signature in the absorption spectra for discriminating coffee origin. Full article

To address the low selectivity in the electrocatalytic conversion of furfural (FFR) to furfuryl alcohol (FFA) under alkaline conditions, a Zn-based metal–organic framework (MBON-2) featuring a 3D hierarchical flower-like architecture self-assembled from nanosheets was synthesized via a simple hydrothermal method. Under optimal conditions, MBON-2 exhibited an extremely high selectivity of FFA (100%) and a high Faradaic efficiency (FE) of 93.19% at −0.2 V vs. RHE. Electrochemical impedance spectroscopy (EIS) revealed the excellent electron transfer and mass transport properties of MBON-2. In addition, in situ Fourier transform infrared (FTIR) spectroscopy studies confirmed the adsorption of FFR molecules onto the Zn and B sites of MBON-2 during the ECH of FFR, providing key insights into the hydrogenation mechanism. The numerous exposed B and Zn sites of the MBON-2, as well as its robust structural stability contributed to its outstanding catalytic performance in the electrochemical hydrogenation (ECH) of FFR. This work provides valuable guidelines for developing efficient Zn-based catalysts for the ECH of FFR. Full article