Runfen Zheng,Lixin Wei,Yuxin Bai,Jianfei Man,Jian Ye,Huiping Zhang,Yihan Wang
To address the issues of poor regeneration performance and high regeneration energy consumption associated with traditional CO2 absorbents, the development of novel phase-change absorbents has become a key area of research. In this study, a new phase-change absorbent system, DEGDEE-AEEA-AMP, is developed, using N-(2-hydroxyethyl)ethylenediamine (AEEA) as the main absorbent, bis(2-ethoxyethyl)ether (DEGDEE) as the phase-separation agent, 2-amino-2-methyl-1-propanol (AMP) as the activator, and water as the solvent. The performance of this system is compared with that of monoethanolamine (MEA) at a 30% mass concentration, which serves as the reference standard. The study includes absorption, desorption, corrosion, cyclic absorption–desorption experiments, and regeneration energy consumption estimations. The results indicate that the volume of the rich phase in the DEGDEE-AEEA-AMP (DAP) system constitutes 56.7% of the total volume. When the AMP mass fraction is 15%, the absorption capacity reaches 2.52 mol·kg–1, which is 14.0% higher than that of MEA. The maximum desorption rate is 13.19 × 10–3 mol·kg–1·s–1, which is 3.39 times higher than that of MEA. The minimum regeneration energy consumption is 2.742 GJ·t–1 CO2, representing a 29.9% reduction compared to 30% MEA. The corrosion rate of the rich liquid is 0.230 mm/a, 1.32 times that of MEA, but it can be significantly reduced by adding anhydrous Na2SO3. When the AMP mass fraction is 15%, the DAP phase-change absorbent system exhibits high absorption and desorption performance, good cyclic stability, and lower regeneration energy consumption.
Fanli Meng,Kun Fu,Xueli Wang,Bonan Ye,Pan Zhang,Lemeng Wang,Dong Fu
Previous work has shown that non-aqueous absorbent composed of dimethyl sulfoxide (DMSO) and 2-ethylhexylan-1-amine (EHA) is superior to commercial monoethanolamine (MEA) in both absorption of CO 2 and desorption. However, the price of DMSO is too high, which leads to the high cost of reagents. It is worthwhile to choose a cheap solvent instead of DMSO, which can also achieve satisfactory absorption and desorption performance. Around this goal, we selected diethylene glycol diethyl ether (DEGDEE) to form a non-aqueous absorbent with EHA and investigated the absorption and desorption performance. The desorption efficiency of 70 wt% EHA +30 wt% DEGDEE was 99 % at 373 K. The desorption efficiency was 89.4 %, and the desorption energy consumption was only 45.1 % of MEA when the water content was 10 wt%. DEGDEE can achieve similar or even better performance than DMSO, while the cost of DEGDEE (12000–31000 RMB/ton, technical grade purity 99 %) is lower than DMSO (40000–48000 RMB/ton, technical grade purity 99 %). In addition, it also has a good recycling capacity. These advantages will certainly endow this newly developed absorbent with great application prospects in the field of CO 2 capture.