Effect of molecular structure on excess molar enthalpy of amine-based carbon dioxide absorbent and water

• Published in: Thermochimica acta 2020-03, Vol.685, p.178514, Article 178514
• Main Authors: Zhang, Ruilei, Chen, Jian, Cao, Guirong, Gu, Hongbiao, Xiao, Ruijie, Chen, Kaiwen
• Format: Article
• Language: English
• Subjects: Amine-based CO2 absorbent; Calorimeter; Excess molar enthalpy; Molecular structure
• ISSN: 0040-6031; 1872-762X
• DOI: 10.1016/j.tca.2020.178514

•HmE of amine-based CO2 absorbents was measured and discussed.•The mixing process between amine-based CO2 absorbents and water is an exothermic process.•The steric hindrance and hydrogen bond affect the HmE value. Amine-based carbon dioxide absorbent has the characteristics of high selective absorption rate and strong absorption capacity and occupies the leading position in the carbon dioxide absorption process. The absorption performance of amine carbon dioxide absorbents is directly related to their thermodynamic properties. Accordingly, for the selection of new absorbents, the important thermodynamic properties such as the excess molar enthalpy of the system must be determined first. In this paper, the excess molar enthalpies for amine-based carbon dioxide absorbents in water were measured with C-80 calorimeter at atmospheric pressure. With the experimental data in this work and the literature data, the relationship between the molecular structure and excess molar enthalpy of amine-based carbon dioxide absorbent was studied.