Scholarlink

<p>In this work, a sustainable ultrasound-assisted strategy using deep eutectic solvents (DES) was developed for lignin recovery from coconut husk, an underused agro-industrial residue. Two ultrasound-assisted extraction approaches (probe and bath) were optimized via Box–Behnken experimental design and merged into a sequential scheme to leverage complementary cavitation dynamics and heat-transfer efficiency. Under optimal conditions, the ultrasonic bath achieved a lignin yield of 100 ± 10% (90&#xa0;min, 65&#xa0;°C, pH 13), while the combined probe → bath sequence delivered 90 ± 10% in 35&#xa0;min, markedly shortening processing time. Relative to a conventional NaOH route, the DES–ultrasound approach increased efficiency by 30%, while replacing bulk alkali with a recyclable solvent system. The recovered lignin exhibited high phenolic content (TPC 430 ± 8&#xa0;mg/g) and strong antioxidant capacity (FRAP 370.3 ± 0.4&#xa0;mg/g; CUPRAC 330.7 ± 0.8&#xa0;mg/g). A recyclability test demonstrated that the DES can be reused at least once with only a moderate decrease in yield (80 ± 2% vs 100 ± 10% with fresh DES). Thermogravimetric analysis showed a DTG maximum at 265&#xa0;°C, consistent with DES-derived lignins. Additionally, FTIR spectroscopy confirmed the presence of characteristic lignin functional groups, while X-ray diffraction (XRD) analysis revealed well-defined peaks associated with lignin nanocrystals, indicating a partially crystalline structure. Overall, the method couples high yield, short cycle time, and a lower chemical footprint, supporting eco-efficient lignin recovery and valorization of coconut husk.</p>

错误：搜索内容不能为空，请输入英文关键词
错误：关键词超出字数限制，请精简
高级检索

Synergistic Ultrasound-Assisted Approach for Enhanced Lignin Extraction from Coconut Husk Using Deep Eutectic Solvents

  • 期刊论文

  • 发表日期：

    2025年11月27日

查看全文
  • Mar Todolí Carbonell,
  • Raquel Sánchez-Romero,
  • Ana Beltrán Sanahuja

摘要

In this work, a sustainable ultrasound-assisted strategy using deep eutectic solvents (DES) was developed for lignin recovery from coconut husk, an underused agro-industrial residue. Two ultrasound-assisted extraction approaches (probe and bath) were optimized via Box–Behnken experimental design and merged into a sequential scheme to leverage complementary cavitation dynamics and heat-transfer efficiency. Under optimal conditions, the ultrasonic bath achieved a lignin yield of 100 ± 10% (90 min, 65 °C, pH 13), while the combined probe → bath sequence delivered 90 ± 10% in 35 min, markedly shortening processing time. Relative to a conventional NaOH route, the DES–ultrasound approach increased efficiency by 30%, while replacing bulk alkali with a recyclable solvent system. The recovered lignin exhibited high phenolic content (TPC 430 ± 8 mg/g) and strong antioxidant capacity (FRAP 370.3 ± 0.4 mg/g; CUPRAC 330.7 ± 0.8 mg/g). A recyclability test demonstrated that the DES can be reused at least once with only a moderate decrease in yield (80 ± 2% vs 100 ± 10% with fresh DES). Thermogravimetric analysis showed a DTG maximum at 265 °C, consistent with DES-derived lignins. Additionally, FTIR spectroscopy confirmed the presence of characteristic lignin functional groups, while X-ray diffraction (XRD) analysis revealed well-defined peaks associated with lignin nanocrystals, indicating a partially crystalline structure. Overall, the method couples high yield, short cycle time, and a lower chemical footprint, supporting eco-efficient lignin recovery and valorization of coconut husk.