在分子层面探索超微孔结构演化和构造性变形煤的甲吸附
Longgui Peng1, Huanquan Cheng1, Fuxing Chen2
1School of Materials Science and Engineering, Xi'an University of Science and Technology, Xi'an, 710054, PR China.
Scientific reports
|November 2, 2024
概括
机械变形显著影响煤炭储存甲的能力. 剪切变形通过增加孔径体积和表面积来增强甲储存,与压缩变形不同.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 能源资源 能源资源
背景情况:
- 构造性变形的煤炭表现出改变的孔隙结构,影响了煤床甲的储存.
- 了解机械变形对煤炭的影响对于优化甲回收至关重要.
研究的目的:
- 研究不同机械变形对煤炭超微孔结构的现场影响.
- 通过分子模拟,分析变形对煤分子中甲吸附能力的影响.
主要方法:
- 用分子模拟来研究压缩和剪切下的煤炭变形.
- 分析的重点是空隙分数,表面积和甲吸附能力的变化.
主要成果:
- 剪切变形 (<20090.23 GPa) 比压缩 (~20 GPa) 更容易发生.
- 剪切变形增加空隙分数 (200%) 和表面积 (30%),促进甲吸附 (42-50 mmol/g).
- 压缩变形减少了这些特性和甲储存 (14-22%).
结论:
- 剪切变形增强了煤炭中的甲储存,其中约7.5 Å 孔极为关键.
- 甲吸附点根据变形模式不同:压缩的异质原子,剪切的C原子.
- 中等等级的Wiser煤在甲储存方面优越;低等级的Wender煤对应变更敏感.
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