Modelling and thermodynamic properties of pure CO_(2)and fue gas sorption data on South African coals using Langmuir,Freundlich,Temkin,and extended Langmuir isotherm models  

作　　者：Major Mabuza Kasturie Premlall Michael O.Daramola 

机构地区：[1]Department of Chemical Engineering,Faculty of Engineering and Technology,Vaal University of Technology,P.O.Box 3595,Secunda 2302,South Africa [2]Department of Chemical,Metallurgical and Materials Engineering,Faculty of Engineering and the Built Environment,Tshwane University of Technology,Private Bag X680,Pretoria 0001,South Africa [3]Department of Chemical Engineering,Faculty of Engineering,Built Environment and Information Technology,University of Pretoria,Hatfeld,Pretoria 0028,South Africa

出　　处：《International Journal of Coal Science & Technology》2022年第3期136-150,共15页国际煤炭科学技术学报（英文）

基　　金：Acknowledgements The authors acknowledge the National Research Foundation(NRF)of South Africa for the fnancial support provided to undertake this research successfully.

摘　　要：Carbon sequestration in unmineable coal seams has been proposed as one of the most attractive technologies to mitigate carbon dioxide(CO_(2))emissions in which CO_(2)is stored in the microporous structure of the coal matrix in an adsorbed state.The CO_(2)adsorption process is hence considered one of the more efective methodologies in environmental sciences.Thus,adsorption isotherm measurements and modelling are key important scientifc measures required in understanding the adsorption system,mechanism,and process optimization in coalbeds.In this paper,three renowned and reliable adsorption isotherm models were employed including Langmuir,Freundlich,and Temkin for pure CO_(2)adsorption data,and the extended-Langmuir model for multicomponent,such as fue gas mixture-adsorption data as investigated in this research work.Also,signifcant thermodynamics properties including the standard enthalpy change(ΔH°),entropy change(ΔS°),and Gibbs free energy(ΔG°)were assessed using the van’t Hof equation.The statistical evaluation of the goodness-of-ft was done using three(3)statistical data analysis methods including correlation coefcient(R^(2)),standard deviation(σ),and standard error(SE).The Langmuir isotherm model accurately represent the pure CO_(2)adsorption on the coals than Freundlich and Temkin.The extended Langmuir gives best experimental data ft for the fue gas.The thermodynamic evaluations revealed that CO_(2)adsorption on the South African coals is feasible,spontaneous,and exothermic;and the adsorption mechanism is a combined physical and chemical interaction between the adsorbate and the adsorbent.

关 键 词：Global warming Flue gas Adsorption Unmineable coal Adsorption models 

分 类 号：O64[理学—物理化学]