Abstract The correlation of CO2 adsorption characteristics with the associated shale samples mineralogy, at various total organic contents, are essential for CO2 sequestration, improved oil recovery, and gas storage operations. In this work, Marcellus shale samples from the U.S.A are studied for their CO2 adsorption capacities in term of equilibrium and kinetics. A series of analyses, including total organic carbon content, X-ray diffraction, Fourier Transform Infra-red Spectroscopy, Field Emission Scanning Electron Microscopy, temperature-programmed desorption, and N2/CO2 adsorption were performed. Gravimetric adsorption technique with magnetic suspension balance at 298 K and up to 20 bars is used to conduct isothermal adsorption and desorption measurements. Considerable organic contents of ≈ 3-18 wt% are observed. Clay minerals such as calcite, illite, kaolinite and smectite are identified with up to 50 wt% ratio of some samples. Porosity and pore distribution analysis illustrate that the samples are mostly mesoporous with hysteresis supporting bottleneck or open ended-shaped pores. The temperature-programmed adsorption encouraged the phenomenon of chemisorption. Though, equilibrium isotherm modelling supported physical and chemical, heterogeneous, and multilayer adsorption. The kinetic investigation by double exponential model shows different rate of adsorption, which can be due to mineralogical alteration, physical properties or organic content. A new empirical model is developed to study the effect of relative pressure and porosity on the adsorption capacity using polynomial curve fitting technique. The model will help to predict the adsorption uptake at different operating pressures and porosity for future studies. The study can demonstrate insightful findings related to CO2 separation, sequestration and gas production for enhanced hydrocarbons recovery.

中文翻译：

---

Marcellus 页岩样品的岩石物理特性及其对 CO2 吸附的影响：平衡、动力学和经验建模研究

摘要 CO2 吸附特性与相关页岩样品矿物学的相关性，在各种总有机含量下，对于 CO2 封存、提高石油采收率和储气作业至关重要。在这项工作中，研究了来自美国的 Marcellus 页岩样品在平衡和动力学方面的 CO2 吸附能力。进行了一系列分析，包括总有机碳含量、X 射线衍射、傅里叶变换红外光谱、场发射扫描电子显微镜、程序升温解吸和 N2/CO2 吸附。重力吸附技术在 298 K 和高达 20 巴的压力下具有磁悬浮天平，用于进行等温吸附和解吸测量。观察到约 3-18 wt% 的相当多的有机物含量。粘土矿物，如方解石，伊利石、高岭石和蒙脱石被鉴定为某些样品的重量比高达 50%。孔隙率和孔隙分布分析表明，样品多为介孔，具有滞后支撑瓶颈或开口状孔隙。程序升温吸附促进了化学吸附现象。不过，平衡等温线模型支持物理和化学、异质和多层吸附。双指数模型的动力学研究显示不同的吸附速率，这可能是由于矿物学改变、物理性质或有机物含量。使用多项式曲线拟合技术开发了一个新的经验模型来研究相对压力和孔隙率对吸附容量的影响。该模型将有助于预测不同操作压力和孔隙率下的吸附量，以供未来研究使用。该研究可以证明与 CO2 分离、封存和气体生产相关的深刻发现，以提高碳氢化合物的采收率。