Pore structure characterization and its effect on methane adsorption on shale kerogen are crucial to understanding the fundamental mechanisms of gas storage, transport, and reserves evaluation. In this study, we use 3D scanning confocal microscopy, scanning electron microscopy (SEM), X-ray nano-computed tomography (nano-CT), and low-pressure N₂ adsorption analysis to analyze the pore structures of the shale. Additionally, the adsorption behavior of methane on shales with different pore structures is investigated by molecular simulations. The results show that the SEM image of the shale sample obviously displays four different pore shapes, including slit pore, square pore, triangle pore, and circle pore. The average coordination number is 4.21 and the distribution of coordination numbers demonstrates that pores in the shale have high connectivity. Compared with the adsorption capacity of methane on triangle pores, the adsorption capacity on slit pore, square pore, and circle pore are reduced by 9.86%, 8.55%, and 6.12%, respectively. With increasing pressure, these acute wedges fill in a manner different from the right or obtuse angles in the other pores. This study offers a quantitative understanding of the effect of pore structure on methane adsorption in the shale and provides better insight into the evaluation of gas storage in geologic shale reservoirs.

孔隙结构表征及其对页岩干酪根上甲烷吸附的影响对于理解储气，运气和储量评估的基本机理至关重要。在这项研究中，我们使用3D扫描共聚焦显微镜，扫描电子显微镜（SEM），X射线纳米计算机断层扫描（nano-CT）和低压N ₂吸附分析以分析页岩的孔隙结构。此外，通过分子模拟研究了甲烷在不同孔隙结构的页岩上的吸附行为。结果表明，页岩样品的SEM图像明显显示出四种不同的孔隙形状，包括狭缝孔，方孔，三角形孔和圆形孔。平均配位数为4.21，配位数的分布表明页岩中的孔隙具有较高的连通性。与三角形孔上的甲烷吸附能力相比，狭缝孔，方孔和圆形孔上的甲烷吸附能力分别降低了9.86％，8.55％和6.12％。随着压力的增加，这些锐利楔形物的填充方式不同于其他孔中的直角或钝角。