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宁-卡帕-卡拉基南冷凝和气凝:结构和胀分析
Javier Alvarez-Valcarce1, Stefania Mottola2, Álvaro González-Garcinuño3
1Department of Chemical Engineering, University of Salamanca, Plaza de los Caídos s/n, 37001, Salamanca, Spain.
International journal of biological macromolecules
|October 30, 2025
概括
这项研究证明了将木质素提升为多孔碳材料. 与冷干燥相比,超临界CO2干燥产生了优质的纳米纤维结构,具有增强的性能.
科学领域:
- 材料科学 材料科学 材料科学
- 绿色化学 绿色化学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 质素的价值化对于可持续的材料合成至关重要.
- 从丰富的生物质中开发新的多孔碳材料具有环境意义.
研究的目的:
- 用于从二硫酸和卡帕-卡拉基安中合成多孔碳材料.
- 研究前体粘弹性和干燥方法 (超临界CO2与冷干燥) 对材料性能的影响.
- 为了优化素的去除和胀行为.
主要方法:
- 凝的形成是通过二硫酸和卡帕-卡拉基安南之间的静电相互作用形成的.
- 使用超临界CO2和冷干燥技术进行干燥.
- 使用风病学,红外光谱学,热重力测量分析和表面积分析进行表征.
- 膨胀比率分析和计算流体动力学 (CFD) 建模.
主要成果:
- 形成了强的凝 (G' > 100,000 Pa),表明了网络的稳定性.
- 超临界CO2干燥导致纳米纤维半孔结构 (10纳米孔径,60-90m2/g表面积),与冷干燥的混乱宏孔结构不同.
- 在通过溶剂交换用超临界CO2干燥之前,通过溶剂交换实现了宁的去除.
- 超临界的二氧化碳干燥材料在伪二次动力学之后表现出高膨胀率 (400-1000%).
结论:
- 干燥过程显著影响以素为基础的碳材料的多孔结构和性能.
- 超临界二氧化碳干燥是一种有前途的方法,用于从木质素中制造高性能多孔碳材料.
- 差价合约 (CFD) 建模提供了对孔隙网络内的流体动态的洞察.
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