Pore Distribution and Variation Rules of the Coal Sample with CO2 Adsorption at Different Pressures Based on Small-Angle X-ray Scattering,Energy & Fuels

当前位置： X-MOL 学术 › Energy Fuels › 论文详情

Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)

Pore Distribution and Variation Rules of the Coal Sample with CO2 Adsorption at Different Pressures Based on Small-Angle X-ray Scattering
Energy & Fuels ( IF 5.2 ) Pub Date : 2021-01-25 , DOI: 10.1021/acs.energyfuels.0c04033
Baisheng Nie _{1,

2,

3} , Kedi Wang _{1,

2} , Qiang Gao _{1,

2} , Mingwei Cao _{1,

2}

Affiliation

Micropores play an important role in gas adsorption and migration. To reveal the variation rule of coal structural parameters in nanosize at different CO₂ adsorption pressures, a CO₂ adsorption in situ small-angle X-ray scattering test is performed in this work. The results show that the adsorption at different pressures somewhat influences the pore diameter distribution. The nanopores (2.13–33.86 nm) inside the coal samples shrink at low pressures (from 0.5 to 1.0 MPa) and swell at higher pressures (1.5 and 2.0 MPa). Regardless of shrinkage or swelling, the deformation increases with the decrease of the pore size. D_s of the samples depends upon the capillary force. The variation of D_s during 600 min (each adsorption pressure adsorbed 120 min) at five different pressures is divided into three stages. For these lower metamorphism samples (V_daf lower than 55%), the micropores are abundant and distributed unevenly, which also leads to relatively high heterogeneity on the pore surface. The variation trend of the pore size distribution with time under different adsorption pressures is correlated with the variation of D_s to some extent. This work enables us to better understand the variation of the pore size and surface fractal dimension during the process of adsorption in multi-points of pressure.

中文翻译：

基于小角度X射线散射的不同压力下CO ₂吸附煤样品的孔隙分布及变化规律

微孔在气体吸附和迁移中起重要作用。为了揭示在纳米尺寸在不同的CO的煤的结构参数的变化规则₂的吸附压力，在CO ₂吸附在原位小角度X射线散射测试在这项工作中被执行。结果表明，不同压力下的吸附对孔径分布有一定影响。煤样品中的纳米孔（2.13–33.86 nm）在低压（0.5至1.0 MPa）下收缩，在高压（1.5和2.0 MPa）下膨胀。无论收缩或溶胀，其变形都随着孔径的减小而增加。样品的D _s取决于毛细作用力。D _s的变化在600分钟内（每个吸附压力吸附120分钟），在五个不同压力下分为三个阶段。对于这些较低变质样品（V _daf低于55％），微孔丰富且分布不均匀，这也导致孔表面的异质性较高。在不同的吸附压力下，孔径分布随时间的变化趋势在一定程度上与D _s的变化有关。这项工作使我们能够更好地理解在多点压力下吸附过程中孔径和表面分形维数的变化。

更新日期：2021-02-04

点击分享查看原文

点击收藏

阅读更多本刊最新论文本刊介绍/投稿指南11