气体水合物的定位中子衍射时间研究:结构II (sII) 转化为结构I (sI)
Y Halpern1, V Thieu, R W Henning
1Energy Systems Division, Argonne National Laboratory, Argonne, Illinois 60439, USA.
Journal of the American Chemical Society
|December 26, 2001
概括
研究人员使用现场衍射观察了气酸盐格子从结构II转变为结构I的转变. 这种结构变化是由二氧化碳 (CO2) 气体交换在酸中引起的,形成混合酸.
科学领域:
- 材料科学 材料科学 材料科学
- 晶体学 晶体学是指结晶学.
- 物理化学 物理化学
背景情况:
- 气体水合物表现出不同的晶体结构 (例如结构I和结构II).
- 了解气体水合物中的相变对于各种应用至关重要,包括储能和碳捕获.
研究的目的:
- 为了研究结构II (sII) 气酸盐格子在现场转换为结构I (sI) 格子.
- 阐明由客分子交换引起的结构转变的机制.
主要方法:
- 飞行时间中子粉衍射被用于现场观测.
- 实验在230至263K的温度下进行,压力高达5000psi.
- 化冰晶被用作起始材料,气用于水合物形成,二氧化碳用于交换.
主要成果:
- 在加热后观察到从D(2) O冰完全转化为sII水合物.
- 在暴露于CO2后,sII酸成功转化为sI酸.
- 由此产生的SI水合物被确定为混合/CO2水合物,表明客分子交换.
结论:
- 在特定条件下,可以在不同的格子 (sII到sI) 之间转换clathrate水合物结构.
- 客分子交换是诱导气体水合物结构转变的可行机制.
- 气体水合物表现为平衡系统,允许封装分子的交换.
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