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To solve the problems of brittleness and formaldehyde emission of melamine-formaldehyde (MF) impregnated decorative paper, a polyacrylate-polyethylene glycol (PEG)-dialdehyde starch (DAS) was used to modify MF. The impregnation adhesive was characterized and the properties of impregnated decorative paper and laminated to plywood were tested. DAS showed better dispersion in the compound resin and higher reactivity with MF compared to the control. The MF can react with active aldehyde groups of DAS by Schiff base reaction and hydroxyl groups of polyacrylate, PEG, and DAS. Thus, the cross-linked structure was formed in the impregnated decorative paper interlayer. At mass ratio of polyacrylate-PEG-DAS:MF= 2:1, the abrasion value, surface bonding strength, fouling capacity of plywood was comparable to MF impregnated decorative paper bonded plywood, improved with crack resistance. In addition, the formaldehyde emission was sharply lowered down with ultra-low value of 0.03 mg/L, which was classified as F * ** * for very high JAS 234:2003 standard (≤0.3 mg/L). [Display omitted] • Dialdehyde modified starch was used as reinforced filler for impregnation adhesive. • MF reacted with aldehyde groups of DAS and hydroxyls of polyacrylate, PEG, and DAS. • The modified impregnated paper showed highly improved toughness and ultra-low formaldehyde emission. • Plywood with modified impregnated paper showed comparable surface properties to MF impregnated one. [ABSTRACT FROM AUTHOR]

Biomass waste, an attractive renewable carbon source, has great potential for carbon reduction. In recent years, high-performance porous carbon materials prepared from agricultural and forestry waste have demonstrated significant promise for applications in the field of dye wastewater purification. In this study, cork waste from Quercus variabilis was utilized as a raw material, melamine as a nitrogen source, and K 2 CO 3 as a green activator to prepare nitrogen-doped porous cork activated carbon (NCAC) with a honeycomb structure. The results showed that NCAC-900, activated at 900 °C, exhibited a highly porous structure with an optimal specific surface area of 2051.35 m2/g and a pore volume of 1.18 cm3/g. To evaluate its adsorption performance towards rhodamine B (RhB), collaborative activation and post-treatment were employed to enhance the adsorption capacity of the dyes. NCAC-900 demonstrated excellent removal efficiency, with a theoretical maximum adsorption capacity of 2552.52 mg/g (at an adsorbent dosage of 0.2 g/L) in a 300 mg/L solution. Nitrogen doping effectively improved the adsorption capacity for RhB, fitting well to the quasi-secondary kinetic model (R2 = 0.9973–0.9999) and Langmuir isotherm (R2 = 0.7697–0.9523) for the adsorption kinetics and equilibrium data. A comparison with the existing literature also revealed that NCAC-900 possessed a remarkably fast adsorption rate of 12.82 mg/g/min. Moreover, the resorption efficiency of NCAC-900 for RhB reached approximately 66.78% after five consecutive adsorption-desorption cycles. Additionally, the obtained nitrogen-doped cork activated carbon exhibited impressive adsorption capabilities of anionic dye Congo red (CR, q m =1499.14 mg/g) and cationic dye methylene blue (MB, q m =571.54 mg/g). In conclusion, our work presented a promising method for preparing excellent NCAC as an efficient adsorbent for wastewater dyes, offering new ideas and theoretical foundations for the high-value utilization of cork materials and the development of cork activated carbon. [Display omitted] • NCAC with a honeycomb structure was prepared using a green activator. • Successful N- doping on the surface of CBC facilitated the adsorption of dyes. • The prepared NCAC offered new ideas for the high-value utilization of cork. • NCAC-900 had maximum theoretical adsorption capacity was 2552.52 mg/g. [ABSTRACT FROM AUTHOR]

• The kinetics of furfural production from Eucalyptus sawdust catalyzed by H-SAPO-34 were well studied. • The maximum yield of furfural of 99.28% was obtained in this study. • H-SAPO-34 possesses efficient catalytic activity for conversion of Eucalyptus sawdust into furfural. • Prediction of furfural yield from the generalized model at 210 °C was present in 3D bars and 2D contour plots. The production of platform chemicals from lignocellulosic biomass is scientifically valuable but technologically challenging. With the aim to establish a green reaction system for the production of furfural from lignocellulosic biomass, in the current work, H-SAPO-34 was investigated for catalysis of the conversion of Eucalyptus sawdust to furfural in γ-valerolactone (GVL). H-SAPO-34 was prepared and characterized by XRD, SEM, FTIR, BET, TGA and ammonia adsorbed FTIR. H-SAPO-34 possesses Brønsted and Lewis acid sites and a large specific surface area. The average pore diameter of H-SAPO-34 was 0.86 nm, which is beneficial for the spread of xylose and furfural and the inhibition of humin production. In this work, a peak furfural yield of 99.28% from Eucalyptus was achieved at 210 °C in 120 min with 30 g/L H-SAPO-34. The Brønsted/Lewis acid bifunctionality and the solvent effect of γ-valerolactone possibly contributed to the high furfural yield from real biomass. The kinetics of the conversion of Eucalyptus sawdust to furfural was also studied, and the activation energy for furfural production was calculated. Additionally, the catalytic activity and stability of the regenerated catalyst were estimated. [ABSTRACT FROM AUTHOR]

• Phosphotungstic acid improved the levulinic acid production in DESs. • The maximum yield of levulinic acid from glucose was 98.9 %. • The maximum yield of levulinic acid cellulose was 88.6 %. • The kinetics of levulinic acid production from cellulose was investigated. A feasible approach to convert glucose and cellulose to levulinic acid applying phosphotungstic acid as catalyst in deep eutectic solvent was proposed. In our study, phosphotungstic acid was considered to be an effective catalyst for levulinic acid production. A considerable yield of levulinic acid (98.9 %) from glucose was achieved using 30 g/L phosphotungstic acid as catalyst at 468 K for 80 min. The peak levulinic acid yield from cellulose was 88.6 % for 120 min at the present temperature and phosphotungstic acid concentration. The reaction system exhibits efficient performance for the conversion of glucose and cellulose, which was due to the combation of phosphotungstic acid and deep eutectic solvent enhanced the levulinic acid production. Additionally, the kinetic study of levulinic acid formation from cellulose was investigated to supply a further insight on the whole biorefining process. The kinetic model agreed with the experiment data well. The activation energy for levulinic acid formation was 47.2 kJ/mol, which obtained from a modified Arrhenius equation. [ABSTRACT FROM AUTHOR]

• SAPO-18 zeolites with Brønsted and Lewis acid sites were used as bifunctional catalyst. • Brønsted to Lewis acid site ratios were adjusted by modifying the Si/Al ratios. • Lower Brønsted to Lewis acid site ratios enhanced furfural production. • Higher Brønsted to Lewis acid site ratios facilitated levulinic acid formation. • The effect of Brønsted to Lewis acid site ratios on the kinetics was investigated. A one-step process was proposed for valorization of corn stover into furfural and levulinic acid catalyzed by SAPO-18 zeolites. With the aim to produce furfural and levulinic acid, the Brønsted to Lewis acid site ratios of SAPO-18 were modified. The influence of reaction temperature, time and the ratios of Brønsted to Lewis acid site on the valorization of corn stover were investigated. At the fixed catalyst concentration of 20 g/L, a furfural yield of 95.1% was observed at 205 °C for 40 min using SAPO-18 with Brønsted to Lewis acid site ratio of 0.11, and a levulinic acid yield of 70.2% achieved at 190 °C for 80 min using SAPO-18 with Brønsted to Lewis acid site ratio of 0.17. The Brønsted to Lewis acid site ratios of SAPO-18 were adjusted by altering the framework Si/Al ratio of SAPO-18. The SAPO-18 with lower Brønsted to Lewis acid site ratios showed higher activity for furfural production from corn stover and that with higher ratios exhibit superior catalytic effect for levulinic acid formation. The kinetic models considering the effect of Brønsted to Lewis acid site ratios agreed with the experiment values well, which provided detailed insights on the conversion of hemicellulose and cellulose fraction of corn stover into furfural and levulinic acid. [ABSTRACT FROM AUTHOR]