Advancing Energy-Efficient Regeneration of N -Monosubstituted Piperazine-Based Absorbents at Reduced Temperatures for CO 2 Capture

作者：Shaojun Jia, Yao Jiang, Chen Wu, Yi Li, Kang Wang, Qi Wang, Peng Cui · 发表于：Industrial & Engineering Chemistry Research · 年份：2025 · DOI：10.1021/acs.iecr.5c00284 · 被引用次数：4 · 研究领域：Carbon Dioxide Capture Technologies、Phase Equilibria and Thermodynamics、Thermal Expansion and Ionic Conductivity

Piperazine (PZ) and its derivatives are highly regarded as promising amine absorbents for CO 2 capture. However, the high energy demand required for their regeneration poses a significant barrier to their further application in CO 2 capture. In this study, we systematically investigate the regeneration performance of PZ and three N -monosubstituted PZ derivatives, N -ethylpiperazine (EPZ), N -(2-hydroxyethyl)piperazine (HEP), and N -aminoethyl piperazine (AEP), for CO 2 capture at various temperatures. The results indicate that the introduction of ethyl and hydroxyethyl groups can enhance the temperature sensitivity of these absorbents during CO 2 capture, leading to a higher cyclic capacity for EPZ and HEP at reduced regeneration temperatures. In particular, the lower regeneration temperature can significantly reduce the regeneration energy consumption for EPZ to as low as 1.98 GJ·t –1 of CO 2 . Moreover, the structure–activity relationships of N -monosubstituted PZ-based absorbents for CO 2 capture were further elucidated through quantitative nuclear magnetic resonance (NMR) and comprehensive evaluation of the CO 2 capture process. This study provides valuable insights into the application of PZ-based absorbents for more energy-efficient CO 2 capture processes.