在Kenaf的活性炭上对醇吸附的动力学和机械学分析
Delia Omenat-Morán1, Carlos J Durán-Valle2, Manuel A Martínez-Cañas3
1Instituto del Corcho, la Madera y el Carbón Vegetal (CICYTEX), Pol. Ind. El Prado, c/Pamplona s/n, 06800 Mérida, Spain.
Molecules (Basel, Switzerland)
|October 26, 2024
概括
凯纳夫活性炭被制造并用酸修饰以进行醇吸附. 孔隙扩散是主要的吸附步骤,受表面化学和π-π堆叠相互作用的影响.
科学领域:
- 材料科学 材料科学 材料科学
- 环境化学环境化学
- 物理化学 物理化学
背景情况:
- 活性炭广泛用于从水溶液中去除吸附剂.
- 肯纳夫 (Hibiscus cannabinus L.) 是一种具有活性碳生产潜力的纤维纤维素生物质.
- 是一种常见的工业污染物,需要有效的去除方法.
研究的目的:
- 为了准备和描述kenaf生物质的活性炭.
- 为了研究醇对这些活性炭的吸附.
- 阐明吸附动力学,机制和影响因素.
主要方法:
- 凯纳夫生物质的碳化和激活 (空气,CO2).
- 活性炭的酸处理 (HNO3,H2SO4).
- 表面特性 (物理和化学) 的表征.
- 吸附实验和动力学建模 (伪二阶,埃洛维奇,班哈姆).
- 密度功能理论 (DFT) 模拟用于吸附机制分析.
主要成果:
- 活性炭主要是巨孔性,其结构因活性化和酸性处理而变化.
- 酸性处理将表面化学物质从性转变为中性.
- 吸附遵循伪二次序和埃洛维奇动力学,表明扩散控制的过程 (班哈姆模型合适).
- DFT模拟显示了π-π堆叠作为一个关键的吸附相互作用,通过氧化增强.
- 醇相互作用强度因氧化功能组类型而异.
结论:
- 来自kenaf的活性炭,特别是在酸性处理后,对醇吸附是有效的.
- 孔隙扩散是醇吸附的速度限制步骤.
- 表面化学,特别是氧化功能组和π-π相互作用,显著影响了吸附效率.
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