在酸性化下的构造煤中孔隙结构的进化对甲脱的影响
Honggao Xie1,2, Xijian Li1,2,3, Feng Xue1,2
1College of Mining, Guizhou University, Guiyang 550025, China.
ACS omega
|September 25, 2023
概括
酸性处理增强了构造煤的孔隙性,改变了孔隙结构,通过降低吸附能力和修改扩散特征来促进甲 (CH4) 脱落.
科学领域:
- 地质化学 地质化学
- 材料科学 材料科学 材料科学
- 化学工程是化学工程的重要组成部分.
背景情况:
- 构造性煤的特性显著影响甲 (CH4) 的吸附和脱附.
- 了解煤酸相互作用对于优化煤床甲 (CBM) 恢复至关重要.
研究的目的:
- 研究单体和混合酸溶液对粉碎构造煤的腐蚀的影响.
- 分析酸化对煤炭孔隙结构的影响及其随后对CH4吸附和脱附的影响.
主要方法:
- 来自费尔煤矿的粉碎煤样本被各种单体酸 (HF,HCl,CH3COOH) 和混合酸溶液处理.
- 分析了煤炭样本的矿物质含量,多孔性,毛孔大小分布和功能组的变化.
- 甲 (CH4) 的吸附能力和脱吸特性是根据孔隙结构的变化进行评估的.
主要成果:
- 单酸腐蚀效应按照以下顺序进行:HF > HCl > CH3COOH.
- 最佳的混合酸比率被确定为6% HCl + 6% HF + 3% CH3COOH + 2% KCl.
- 酸化溶解了矿物颗粒,增加了多孔性,转换了多孔类型 (过渡到中/宏),减少了墨水瓶毛孔,增加了裂/开放的毛孔.
- 酸性煤的芳香度更高,含氧功能组增加,氧含量降低.
- 甲 (CH4) 吸附能力下降,由于扩散变化 (Knudsen 到过渡性),吸附体积减少,孔喉比和曲性,促进了脱吸.
结论:
- 酸性处理有效地改变了构造煤的孔状结构,增强了孔状性并改变了孔状尺寸分布.
- 观察到的孔隙结构和表面化学的变化显著降低了甲 (CH4) 的吸附能力,从而促进了脱吸.
- 由于酸引起的扩散系数,吸附体积,孔喉比率和曲度的变化是控制从构造煤中增强的CH4脱附的关键因素.
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