Low-temperature hydrothermal liquefaction of pomelo peel for production of 5-hydroxymethylfurfural-rich bio-oil using ionic liquid loaded ZSM-5

Ionic liquid loaded ZSM-5 with high stability and catalytic performance was used for hydrothermal liquefaction (HTL) of pomelo peel for the first time. Bio-oil obtained at 200 °C had the highest yield (29.21 wt%) and high heating value (21.41 MJ/kg), with main constituents of 5-hydroxymethylfurfural (5-HMF, 50.10%), 3-Pyridinol (19.8%) and pentanoic acid (5.35%). The higher 5-hydroxymethylfurfural yield obtained using ionic liquid loaded ZSM-5 was further compared to other studies (0-50%). In comparison to high-temperature HTL, catalytic HTL with ionic liquid loaded ZSM-5 led to lower activation energy requirements (31.93 kJ·mol^-1) for the conversion of glucose into 5-HMF. Additionally, the catalysts showed excellent recyclability, with 19.68 wt% of bio-oil containing 59.6% of light oil obtained after 5 cycles. Hence, this study presents a novel approach for the catalytic conversion of lignocellulosic biomass into 5-HMF-rich bio-oil for energy and green chemistry applications.

Optimization of bleaching process for cellulose extraction from apple and kale pomace and evaluation of their potentials as film forming materials

Celluloses from apple and kale pomaces were extracted through sequentially chemical treatments, characterized, and evaluated for the film forming property. Since bleaching step is critical to cellulose quality, bleaching conditions including concentration of bleaching agent (NaClO) (0.5-3 %), temperature (60-80 °C) and time (1-2 h) were optimized. NaClO concentration and temperature exhibited significant impact on the quality of celluloses. Excessive bleaching conditions caused severe oxidation of celluloses and significantly reduced their dimension. The optimum bleaching conditions for apple pomace were identified as 1-1.5 % NaClO at 80 °C for 1 h, resulting in cellulose yield of 7.9 %, water retention value of 2.96, and whiteness index of 72.36. Morphological analysis of optimum apple pomace-celluloses revealed their long-shaped structure with 500-750 μm in length and 20-25 μm in width. The prepared cellulose films had high transparency and good mechanical strength. This study provided new insight in converting fruit processing byproducts into high quality celluloses.

Totally green cellulose conversion into bio-oil and cellulose citrate using molten citric acid in an open system: synthesis, characterization and computational investigation of reaction mechanisms

The simultaneous transformation of crystalline or amorphous cellulose into a furan-based bio-oil and cellulose citrate was realized avoiding the use of strong inorganic acids, drastic conditions, enzymatic treatments or microorganism fermentation. This innovative method is very eco-friendly and involves the use of molten citric acid under solvent free conditions at atmospheric pressure. An accurate discussion on chemical composition of the bio-oil enriched in bioprivileged molecules as well as structural and morphological characterization of cellulose citrate was reported. Moreover, mechanistic hypotheses were formulated on the basis of experimental findings and detailed DFT quantum-mechanical simulations were carried out to confirm, step by step, the proposed reaction paths.

Innovative and efficient conversion of cellulose in furan-based bio-oil and cellulose citrate.

Green synthesis of copper nanoparticle using ionic liquid-based extraction from Polygonum minus and their applications

The present work reports the extraction of phenolic compounds from Polygonum minus using ionic liquid as extracting solvent. In this work, 1-Butyl-3-methylimidazolium hydrogen sulfate [BMIM][HSO₄] was used for the extraction of bioactive compounds. Accordingly, ionic liquids based microwave-assisted extraction treatment for separating of bioactive compounds from polygonum minus was first performed in the present study. The results obtained in this work have high extraction yield in comparison with conventional solvent. UV/Vis results showed that microwave synthesis was fast, well dispersed and nanosized copper nanoparticle (CuNPs) in comparison with conventional synthesis. CuNPs was characterised by X-Rays diffractometer (XRD), Fourier transform infrared (FTIR), dynamic light scattering (DLS), field emission scanning electron microscopy combined with energy dispersive x-rays (FESEM-EDX), and thermogravimetric analysis (TGA). All the instrumental analyses confirmed the particles were nanosized. Furthermore, the antibacterial activity of as-synthesised CuNPs showed effective inhibitory zone against three different bacteria. The photocatalytic degradation of copper nanoparticles was studied using methylene blue (MB) and methyl orange (MO) dyes under UV light and degraded 99.9% within short time 8 and 7 min.

Synthesis of different structured FePO4 for the enhanced conversion of methyl cellulose to 5-hydroxymethylfurfural

Catalytic mechanism of FePO₄ for the conversion of methyl cellulose into 5-HMF.