ENERGY & FUELS
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2025
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IF 5.3
Qing Sun,Qingqiao Zhao,Lifang Zhang,Fengjun Ming,Weidong Zhang
Water lean solvents have received growing attention for CO2 capture due to their low solvent evaporation and potential for energy saving. The previous study mainly focused on the organic diluent selection and paid less efforts on the amine effect. In this study, 11 types of amines with representative structures were selected to explore the effect of amine on CO2 loading and CO2 distribution with poly(ethylene glycol) dimethyl ether (NHD) as organic diluent. Based on the cyclic loading and reaction heat comparison, N-ethylethanolamine (EAE) was selected and the EAE/NHD water lean solvent was constructed. The liquid–liquid phase separation was found in the EAE/NHD/H2O system with more than 95% CO2 concentrated in the lower phase, which yielded high cyclic loading and benefited regeneration energy consumption. The water content effect was further investigated in terms of CO2 cyclic loading and phase separation behaviors, suggesting that EAE/NHD/H2O with a mass ratio of 3:6:1 exhibited the excellent performance of 3.03 mol·kg–1 cyclic loading and 2.27 GJ·t–1 CO2 regeneration energy consumption. 13C NMR and quantum chemistry calculations were conducted to explain the reaction route and phase change mechanism. The large difference between the ion–dipole interaction of ion–H2O and the molecule–molecular interaction of ion-NHD was regarded as the main reason for phase separation. The long-term tests indicated the cycling stability and low corrosivity of EAE/NHD/H2O, as exhibited by the stable CO2 cyclic loading during 8 runs of absorption–desorption and lower corrosivity rate of carbon steel than 30 wt % MEA aqueous solution.
研究领域:
化学工程
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环境科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2023
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IF 15.1
Fen Liu,Jingcong Zhang,Wenxuan Bai,Jinxiang Chen,Zhiping Gu,Jiang Yu
To reduce the energy consumption of regeneration for HCl absorption, and to recover HCl to high-value products, a sustainable phase-change system was constructed with N-methyldiethanolamine (MDEA) and polyethylene glycol dimethyl ether (NHD) in this paper. The MDEA/NHD phase change absorbent for HCl absorption is optimized by the ternary phase diagram and phase behavior of MDEA/NHD/HCl system. The results demonstrate that the biphasic system can be constructed with the mass fraction of HCl less than 28% and NHD component in the range of 23.0% ∼ 95.3%. Because of the higher stability of protonated MDEA·HCl than that of NHD·HCl, HCl molecules are mainly enriched in MDEA phase containing the volume ratio of less than 1/3 and partition coefficient over 100 at the neutral point. Therefore, only MDEA phase needs to be recycled, which results in reducing the circulation of regeneration by approximately 68%. Moreover, concentrated HCl in anhydrous MDEA phase could further prevent the side reaction of OER and improve the Faradaic efficiency toward HER and CER to reach 98.5% and 90.5% at 55 °C, respectively. And the energy consumption of regeneration is reduced to 0.37 GJ/t(absorbed HCl) in MDEA/NHD biphasic absorbent compared with that of 2.3 GJ/tCO 2 by DMX™ phase change absorption for CO 2 . By enhancing the conductivity and decreasing the viscosity of MDEA phase, introducing water in MDEA/NHD/HCl solution within 5% could significantly promote the current density and maintain high Faradaic efficiency toward HER and CER as 89.0% and 86.8%, respectively. Therefore, it is a promising technology to be applied in industry.
研究领域:
化学工程
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环境科学
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2020
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IF 3.573
Yijiao Qiu,Houfang Lu,Yingming Zhu,Yingying Liu,Kejing Wu,Bin Liang
Phase-change solvents exhibit the promising potential to reduce the regeneration energy for CO2 capture. In this paper, 3-dimethylaminopropylamine (DMAPA) with intramolecular primary and tertiary amino groups was mixed with solvent NHD and water for phase-change absorption of CO2 in the model flue gas. The results show that the homogeneous mixture changes into two phases after CO2 absorption when NHD/H2O ranges from 9:1 to 5:5 and 90% of CO2 is enriched in the lower phase with only 23% of the total volume. The absorption loading reaches 1.06 mol CO2/mol amine, the phase separation time for DMAPA–NHD–H2O is only 14% of that for MEA–SA–H2O, and the viscosity of the lower phase is only 37.14 mPa·s when DMAPA and NHD/H2O are 1 M and 8:2, respectively. Analysis of the reaction mechanism shows that the primary amino group of DMAPA initially reacts with CO2 and the tertiary amino group captures proton of zwitterionic intermediate as an acceptor. The mixed-amine effect is suggested to explain the high absorption performance of the DMAPA–NHD–H2O mixture. The energy estimation shows that the regeneration energy is reduced by 42% compared with that of the 5 M MEA solution, which confirms the advantage of phase-change absorption using DMAPA–NHD–H2O.
研究领域:
化学工程
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环境科学
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能源技术
✓ 已验证
产品关联
DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Jia Liu,Houfang Lu,Yingying Liu,Kejing Wu,Binshen Wang,Yingming Zhu,Bin Liang
As a highly toxic gas, H2S is conventionally removed via a chemical absorption process. However, the high regeneration energy is still a challenge. 1,5-Diazabicyclo[4.3.0]non-5-ene (DBN)/polyethylene glycol dimethyl ether (NHD) solution was developed as an efficient nonaqueous phase change absorbent for the removal of H2S with low energy consumption. A homogeneous DBN/NHD solution turns into two immiscible liquid phases upon the absorption of H2S, which results from the higher polarity of the product compared to that of the original solution. The loading capacity of H2S can reach 0.16 g·g–1 solvent even under a H2S partial pressure of 10 kPa at 30 °C. After absorption, more than 94% of the absorbed H2S is concentrated in the lower phase, which can be regenerated at 90 °C with an energy consumption estimated to be 1.69 GJ·t–1 H2S. The regeneration energy is 58% lower than that of 30 wt % aqueous solution of N-methyldiethanolamine. 81% of the initial H2S loading was maintained after 4 absorption–desorption cycles. In addition, the selectivity of DBN/NHD solution to absorb H2S from N2 containing H2S and CO2 or from N2 containing H2S and CH4 was investigated. It shows that the selectivity increases with the increase in the volume ratio of H2S to CO2, which can be as high as 27.8 when the ratio is 1:1. CH4 cannot be absorbed in the DBN/NHD solution in the presence of H2S and N2.
研究领域:
化学工程
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
FUEL
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2018
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IF 4.908
Jiajun Gao,Shuang Zhu,Yafen Dai,Chunyan Xiong,Chunxi Li,Weimin Yang,Xingmao Jiang
Polyethylene glycol (PEG) is not satisfactory for the removal performance of thiophenic sulfurs, e.g., low S-partition coefficient K N (S). The unsatisfactory K N may be due to relatively low content of active O atom on PEG. Modification replacing – OH group with – OCH 3 group can produce modified PEGs that have the higher active O-content. Polyethylene glycol dimethyl ether, which was commonly known as NHD, showed the higher K N than PEG. Its K N for dibenzothiophene (DBT) can reach as high as 3.99. The higher K N was dominantly ascribed to the contribution of the active O atom: (1) H-bonding with DBT; (2) group similarity between C-O-C and C-S-C. Further, methoxy polyethylene glycol (mPEG) showed the best selectivity for DBT to toluene, compared with NHD and PEG. The best selectivity of mPEG may be attributed to its higher active O-content than PEG’s and its stronger polarity than NHD’s. Moreover, NHD and mPEG can be regenerated and recycled for several times without significantly decreasing the desulfurization performance.
研究领域:
化学工程
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环境科学
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材料科学
✓ 已验证
产品关联
DOI
高影响因子
Separations
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2025
·Vol. 12
·期 8
·198
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IF 2.7
Yan Wu,Zicheng Wang,Hui Yu,Bin Ding,Ke Fei,Xueli Ma,Baoshen Xu,Yonghu Zhang,Xiaoning Fu,Bowen Ding,Nan Li
Developing and utilizing capture and storage technologies for CO2has become a critical research topic due to the significant greenhouse effect caused by excessive CO2emissions. A conventional physical absorption process for CO2capture is polyethylene glycol dimethyl ether (NHD); however, its limited application range is caused by its poor absorption of CO2at low pressures. In this work, the CO2absorption of NHD was enhanced by combining NHD with a novel chemical absorbent 2-methylimidazole (2-mIm)-ethylene glycol (EG) solution to improve CO2absorption. Viscosity and CO2solubility were examined in various compositions. The CO2solubility in the mixed solution was found to be at maximum when the mass fractions of NHD, 2-mIm, and EG were 20%, 40%, and 40%, respectively. In comparison to pure NHD, the solubility of CO2in this mixed solution at 30 °C and 0.5 MPa increased by 161.2%, and the desorption heat was less than 30 kJ/mol. The complex solution exhibits high selectivity and favorable regeneration performance in the short term. However, it is more sensitive to moisture content. The results of this study can provide important data to support the construction of new low-energy solvent systems and the development of novel CO2capture processes.
研究领域:
化学工程
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环境科学
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碳捕集与封存
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温室气体减排
✓ 已验证
产品关联
DOI
高影响因子
危险品化学品经营许可证（带存储）