煤体吸附CH4及CO2热力学特性试验研究  

Experimental study on thermodynamics characteristics of CH4 and CO2 adsorption on coal

作　　者：林海飞 蔚文斌[1] 李树刚 严敏 白杨[1] LIN Haifei;WEI Wenbin;LI Shugang;YAN Min;BAI Yang(School of Safety Science ＆ Engineering,Xi＇an University of Science ＆ Technology,Xi＇an Shaanxi 710054,China;Western Mine Exploitation and Hazard Prevention of Ministry of Education,Xi＇an Shaanxi 710054,China)

机构地区：[1]西安科技大学安全科学与工程学院,陕西西安710054 [2]教育部西部矿井开采及灾害防治重点实验室,陕西西安710054

出　　处：《中国安全科学学报》2018年第6期129-134,共6页China Safety Science Journal

基　　金：国家自然科学基金重点资助(51734007);国家自然科学基金资助(51674192,51604220)

摘　　要：为揭示煤吸附CH4和CO2热力学机制,选取新疆硫磺沟的煤样进行不同温度下的CH4和CO2等温吸附试验,利用Langmuir、Freundlich、D-R吸附理论模型对等温吸附曲线进行拟合,基于吸附势能理论研究煤样吸附CO2和CH4的热力学特性。研究表明：不同温度条件下煤样吸附CH4和CO2曲线均符合Langmuir、Freundlich、D-R模型;CH4和CO2吸附势能均随着吸附量增大而降低,其等量吸附热和吸附熵变均随着吸附量增加呈上升趋势,并且CO2的吸附势能、吸附热、吸附熵变均大于CH4;CH4和CO2吸附熵随温度升高总体呈降低趋势,其吸附势能不仅受表面力场影响,也受吸附焓和吸附熵的影响;CO2等量吸附热受分子间竞争及微孔填充的影响。吸附热力学参数能用来表征煤体吸附特性,可从热力学角度揭示煤体表面竞争吸附的实质。To reveal the adsorption thermodynamic mechanism of CO2 and CH4 on coal,isothermal adsorption experiments at different temperatures were carried out with typical coal samples taken from Xinjiang Liuhuanggou. The Langmuir,Freundlich and D-R adsorption were used to fit the isothermal adsorption curves, based on the theory of adsorption potential energy, coal sample adsorption thermodynamic characteristics of CO2 and CH4 were researched. The results indicate that the isothermal adsorption curve under different temperatures of CH4 and CO2 adsorption are in line with Langmuir,Freundlich and D-R equation model,that there is a negative correlation between the adsorption potential energy of CH4 and CO2 and the adsorption quantity,and there is a positive correlation between both the isosteric heat and entropy change and the adsorption quantity,the adsorption potential energy,isosteric heat,adsorption entropy change CO2 are all greater than those of CH4,that with increasing of temperature,the adsorption entropy of CH4 and CO2 decreased,that the changes in adsorption potential of CH4 and CO2 are not only affected by the surface force but also by the enthalpy of adsorption and adsorption entropy,that the CO2 isosteric adsorption heat is affected by intermolecular competition and micropore filling,and that the adsorption thermodynamics parameters can be used to characterize the adsorption performance of coal sample,and reveal the nature of coal surface competitive adsorption.

关 键 词：甲烷 二氧化碳 吸附势能理论 等温吸附 吸附热 

分 类 号：X936[环境科学与工程—安全科学]