C_2H_6,CH_4在高岭石表面竞争吸附的分子模拟  

Molecular Simulation of C_2H_6,CH_4 Competitive Adsorption on Kaolinite Surface

作　　者：张彬[1] 康天合[1] 康健婷[1] 宋正平 ZHANG Bin;KANG Tianhe;KANG Jianting;SONG Zhengping(Key Laboratory of Insitu Property Improving Mining of Ministry of Education,Taiyuan University of Technology,Taiyuan 030024,China)

机构地区：[1]太原理工大学原位改性采矿教育部重点实验室,太原030024

出　　处：《太原理工大学学报》2019年第3期297-302,共6页Journal of Taiyuan University of Technology

基　　金：国家自然科学基金资助项目(U1810102)

摘　　要：为阐明C_2H_6/CH_4在高岭石表面的竞争吸附机理,采用蒙特卡洛法模拟计算了C_2H_6/CH_4单组分气体和混合气体在高岭石表面的吸附量、吸附热和相互作用能及其随压力的变化规律,并分析了吸附密度的分布规律。模拟结果表明:C_2H_6/CH_4单组分气体在高岭石的吸附量均呈先增大后趋于平衡的规律,符合Langmuir模型,且相同温度压力条件下,C_2H_6吸附量大于CH_4吸附量;高岭石吸附C_2H_6/CH_4混合气体时,C_2H_6的吸附具有明显的竞争优势;C_2H_6和CH_4的吸附热均小于42kJ/mol,说明C_2H_6和CH_4在高岭石中的吸附属于物理吸附;高岭石和C_2H_6之间的相互作用能大于高岭石和CH_4之间的相互作用能,表明高岭石和C_2H_6具有更强的相互作用;C_2H_6密度分布曲线的峰值大于CH_4,且吸附距离更小,也说明了C_2H_6比CH_4具有更强的吸附能力。研究结果揭示了高岭石对CH_4/C_2H_6混合气体的吸附特性,为阐明C_2H_6和CH_4在黏土矿物中的赋存机理提供了一定的理论基础。In order to elucidate the competitive adsorption mechanism of CH 4 and C 2H 6 in kaolinite, the adsorption capacity, adsorption heat and interaction energy of C 2H 6/CH 4 single-component gas and mixed gas on kaolinite surface were calculated by Monte-Carlo method, and the distribution of adsorption density was also analyzed. The simulation results show that the adsorption quantity of C 2H 6/CH 4 single component gas in kaolinite first increased and then tended to balance, in accordance with the Langmuir model. The adsorption heat of both C 2H 6 and CH 4 was less than 42 kJ/mol, indicating that the adsorption of C 2H 6 and CH 4 in kaolinite belonged to physical adsorption. The interaction between kaolinite and C 2H 6 was greater than that between kaolinite and CH 4, indicating that kaolinite and C 2H 6 have stronger interactions. The results reveal the adsorption characteristics of kaolinite for CH 4/C 2H 6 mixed gas and provides a theoretical basis for clarifying the occurance mechanism of C 2H 6 and CH 4 in clay minerals.

关 键 词：高岭石 C2H6 CH4 竞争吸附 分子模拟 

分 类 号：TE319[石油与天然气工程—油气田开发工程]