在金属有机框架中控制气体吸收,记录氨吸收
1Department of Chemistry , Massachusetts Institute of Technology , 77 Massachusetts Avenue , Cambridge , Massachusetts 02139 , United States.
Journal of the American Chemical Society
|February 10, 2018
概括
新的金属有机框架 (MOF) 为食品安全和个人保护提供了卓越的氨 (NH3) 吸附能力. 这些材料在静态和动态能力上显著优于当前标准.
科学领域:
- 材料科学
- 化学工程
- 吸附科学
背景情况:
- 氨 (NH3) 对食品供应链至关重要,但存在毒性和腐蚀性风险.
- 目前用于捕获氨的材料在容量和/或亲和力方面存在局限性.
- 需要先进的吸附材料来有效地保护和减轻氨.
研究的目的:
- 开发具有增强氨吸附性的新型微孔三酸盐金属有机框架 (MOF).
- 调查这些MOF中控制氨吸收和稳定的结构性质关系.
- 建立静态和动态氨容量的性能基准.
主要方法:
- 一系列具有开放金属位点的微孔三酸金属有机框架的合成.
- 在各种条件下对氨吸附等温体和动力学进行表征.
- 与行业标准活性炭和先前最先进的材料进行比较分析.
- 使用同结构MOF (Co,Ni,Cu) 和运动分析进行结构功能关系研究.
主要成果:
- 在1bar下记录最多19.79 mmol NH3 g-1的静态氨容量,超过100%的活性炭.
- 在个人防护应用中,氨的动态容量为8.56 mmol g-1,比以前的最佳容量高27%.
- 确定了与金属水复合体中的水替代率相关的稳定性趋势,提供了设计见解.
结论:
- 具有开放金属位点的微孔三酸盐MOF代表了氨捕获技术的重大进步.
- 这些MOF在批量清除氨和个人防护设备方面表现出卓越的性能.
- 该研究提供了用于强相互作用气体的稳定和高容量的MOF吸收剂的关键描述.
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