Optimization of Alkaline Extraction of Xylan-Based Hemicelluloses from Wheat Straws: Effects of Microwave, Ultrasound, and Freeze–Thaw Cycles

Polymers, Journal Year: 2023, Volume and Issue: 15(4), P. 1038 - 1038

Published: Feb. 19, 2023

The alkaline extraction of hemicelluloses from a mixture three varieties wheat straw (containing 40.1% cellulose, 20.23% xylan, and 26.2% hemicellulose) was analyzed considering the following complementary pre-treatments: freeze–thaw cycles, microwaves, ultrasounds. two cycles approach selected based on simplicity energy savings for further analysis optimization. Experiments planned with Design Expert were performed. regression model determined through response surface methodology severity factor (defined as function time temperature) alkali concentration variables then used to optimize process in multi-objective case possibility use pulping. To show properties chemical structure separated hemicelluloses, several analytical methods used: high-performance chromatography (HPLC), Fourier-transformed infrared spectroscopy (FTIR), proton nuclear magnetic resonance (1H-NMR), thermogravimetry derivative (TG, DTG), scanning electron microscopy (SEM). verified experimental optimization result indicated obtaining material containing 3.40% glucan, 85.51% 7.89% arabinan. association hot allows partial preservation hemicellulose polymeric structure.

Language: Английский

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Conversion of flat to cylindrical hydrogel structures by asymmetric crosslinking and ionic exchange

Chemical Engineering Journal, Journal Year: 2024, Volume and Issue: 490, P. 151906 - 151906

Published: May 6, 2024

Language: Английский

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Investigation of bio-based rigid polyurethane foams synthesized with lignin and castor oil

Scientific Reports, Journal Year: 2024, Volume and Issue: 14(1)

Published: June 12, 2024

Abstract In this study, polyurethane (PU) foams were manufactured using kraft lignin and castor oil as bio-based polyols by replacing 5–20 wt% 10–100 of conventional polyol, respectively. To investigate the effects unmodified on PU foam production, reactivity morphology within composites was analyzed well mechanical thermal properties resulting foams. Bio-based production carried out after characterizing reagents used in foaming process (including hydroxyl group content, molecular weight distribution, viscosity). compare foams, control produced without any polyol under same experimental conditions. For lignin-incorporated two types, LPU lpu, with index ratio 1.01 1.3, The compressive strength increased content from 5 (LPU5: 147 kPa) to 20 (LPU20: 207 kPa), although it remained lower than that (PU0: 326 kPa). Similarly, lpu (pu0: 441 values 164 kPa (lpu5), 163 (lpu10), 167 (lpu15), (lpu20). At 10 both (LPU10 lpu10) exhibited smallest most homogenous pore sizes structures. oil-incorporated an 1.01, denoted CPU, increasing resulted larger cell void fractions, transitioning open-cell structure decreasing 284 (CPU10) 23 (CPU100). Fourier transform infrared (FT-IR) results indicated formation characteristic urethane linkages confirmed less reactive isocyanate compared traditional polyol. Thermogravimetric analysis (TGA) showed incorporating affected decomposition behavior. stability improved char yields 11.5 (LPU5) 15.8 (LPU20) 12.4 (lpu5) 17.5 Conversely, addition decreased stability, 10.6 4.2 This research provides a comprehensive understanding biomass-derived (lignin oil), suggesting their potential for value-added utilization products.

Language: Английский

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How lignin biosynthesis responds to nitrogen in plants: a scoping review

Plant Biology, Journal Year: 2024, Volume and Issue: 26(6), P. 881 - 895

Published: July 19, 2024

Abstract Nitrogen (N) plays a critical role in the functioning of key amino acids and synthetic enzymes responsible for various stages lignin biosynthesis. However, precise mechanisms through which N influences biosynthesis have not been fully elucidated. This scoping review explores how responds to plants. A systematic search literature several databases was conducted using relevant keywords. Only 44 1842 selected studies contained range plant species, experimental conditions, research approaches. Lignin content, structure, biosynthetic pathways response are discussed, possible under low proposed. Among studies, 64.52% reter content found negative correlation between availability content. Usually, high decreases delays cell lignification, increases p‐hydroxyphenyl propane (H) monomer regulates synthesis expression genes (PAL, 4CL, CCR, CAD, COMT, LAC, POD) encoding miRNAs transcription factors (e.g., MYB, bHLH). deficiency enhances accumulation phenylpropanoids, phenolics, soluble carbohydrates, indirect changes phytohormones, secondary metabolites, etc. provides new insights important references future on regulation

Language: Английский

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Lignin/polysaccharide composite: A nature-made match toward multifunctional bio-based materials

Progress in Materials Science, Journal Year: 2024, Volume and Issue: unknown, P. 101383 - 101383

Published: Oct. 1, 2024

Language: Английский

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