Adsorption behavior of CO_(2)/H_(2)S mixtures in calcite slit nanopores for CO_(2) storage:An insight from molecular perspective  

作　　者：Cheng Qian Zhen-Hua Rui Yue-Liang Liu Kai Du Chen Liu Yang Zhao Xiao-Min Ma 

机构地区：[1]State Key Laboratory of Petroleum Resources and Engineering,China University of Petroleum,Beijing,102249,China [2]College of Petroleum Engineering,China University of Petroleum,Beijing,102249,China [3]College of Carbon Neutrality Future Technology,China University of Petroleum,Beijing,102249,China [4]College of Petroleum,China University of Petroleum-Beijing at Karamay,Karamay,83400,Xinjiang,China [5]College of Mining Engineering,Taiyuan University of Technology,Taiyuan,030024,Shanxi,China

出　　处：《Petroleum Science》2024年第4期2444-2456,共13页石油科学（英文版）

基　　金：financial support from the National Natural Science Foundation of China (Grant No.52004320);the Science Foundation of China University of Petroleum,Beijing (No.2462021QNXZ012,No.2462022BJRC001,and No.2462021YJRC012);the funding from the State Key Laboratory of Petroleum Resources and Engineering (No.PRP/indep-1-2103)。

摘　　要：It is acknowledged that injecting CO_(2) into oil reservoirs and saline aquifers for storage is a practical and affordable method for CO_(2) sequestration.Most CO_(2) produced from industrial exhaust contains impurity gases such as H_(2)S that might impact CO_(2) sequestration due to competitive adsorption.This study makes a commendable effort to explore the adsorption behavior of CO_(2)/H_(2)S mixtures in calcite slit nanopores.Grand Canonical Monte Carlo(GCMC)simulation is employed to reveal the adsorption of CO_(2),H_(2)S as well as their binary mixtures in calcite nanopores.Results show that the increase in pressure and temperature can promote and inhibit the adsorption capacity of CO_(2) and H_(2)S in calcite nanopores,respectively.CO_(2)exhibits stronger adsorption on calcite surface than H_(2)S.Electrostatic energy plays the dominating role in the adsorption behavior.Electrostatic energy accounts for 97.11%of the CO_(2)-calcite interaction energy and 56.33%of the H_(2)S-calcite interaction energy at 10 MPa and 323.15 K.The presence of H_(2)S inhibits the CO_(2) adsorption in calcite nanopores due to competitive adsorption,and a higher mole fraction of H_(2)S leads to less CO_(2) adsorption.The quantity of CO_(2) adsorbed is lessened by approximately 33%when the mole fraction of H_(2)S reaches 0.25.CO_(2) molecules preferentially occupy the regions near the po re wall and H_(2)S molecules tend to reside at the center of nanopore even when the molar ratio of CO_(2) is low,indicating that CO_(2) has an adsorption priority on the calcite surface over H_(2)S.In addition,moisture can weaken the adsorption of both CO_(2) and H_(2)S,while CO_(2) is more affected.More interestingly,we find that pure CO_(2) is more suitable to be sequestrated in the shallower formations,i.e.,500-1500 m,whereas CO_(2)with H_(2)S impurity should be settled in the deeper reservoirs.

关 键 词：Adsorption behavior CO_(2)/H_(2)S binary mixtures Molecular perspective Calcite slit nanopores CO_(2)sequestration 

分 类 号：TE311[石油与天然气工程—油气田开发工程]