APPLIED ENERGY
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2019
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IF 8.426
Hui Guo,Chenxu Li,Xiaoqin Shi,Hui Li,Shufeng Shen
High energy consumption for CO 2 capture using aqueous amines is still a major drawback limiting its deployment on a global scale. In this work, the absorption-desorption performance of CO 2 into several blends of monoethanolamine (MEA) or diethanolamine (DEA) with glycol ethers (2-methoxyethanol (2ME) and 2-ethoxyethanol (2EE)) as nonaqueous solvents has been investigated at ambient pressure. Reaction mechanisms and the relative heat duty for these nonaqueous systems were also explored and compared with those of the aqueous MEA. Results showed that the nonaqueous absorbents with 5.0 M MEA had comparable absorption capacity with aqueous 5.0 M MEA and higher desorption efficiency resulting in a larger cyclic capacity (1.45 mol kg −1 ). Higher partial pressure ratio of CO 2 to solvent vapor under the desorption conditions was also observed for these nonaqueous systems. 13 C NMR, FTIR spectra and online conductivity analysis provided evidences that CO 2 can react with MEA in nonaqueous solvents forming the ionic couples (i.e. protonated MEA and carbamate) as well as carbamic acid at high CO 2 loading. The mixture of MEA and 2ME or 2EE could significantly reduce the energy consumption by about 55% as compared to the benchmark aqueous 5.0 M MEA system.
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
JOURNAL OF INDUSTRIAL AND ENGINEERING CHEMISTRY
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2025
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IF 6
Qinghai Long,Jing Wang,Tiantian Ping,Shufeng Shen
Nonaqueous absorbents have shown great potential in lowering regeneration energy for energy-efficient CO 2 capture. The effect of reaction media with varying solvent characteristics (polarity, solubility parameter and dielectric constant) on kinetic behaviors deserves to be discovered. In this work, CO 2 absorption flux against CO 2 partial pressure was determined in a stirred cell reactor at temperatures of 283.2–303.2 K with 1.0–5.0 mol L −1 2-(butylamino)ethanol (BAE) in nonaqueous 2-butoxyethanol (2-BE). Physicochemical properties and the physical mass transfer coefficients were also measured and represented by proposed correlations. The overall reaction rate constants were derived under the well-defined pseudo-first-order regime conditions. The partial reaction order with respect to BAE was found to be about 2.0 in 2-BE and 1.0–1.3 in water respectively, which reveals that the formation of ionic products may be highly depressed in solvent with low Hansen solubility parameter (HSP) resulting in the increasing reaction order. The overall third-order kinetic data can be well represented by termolecular mechanism model with AARD of 10.5 %. The findings will provide fundamental support for further pilot-scale performance demonstration.
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
ENERGY & FUELS
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2022
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IF 4.654
Meisi Chen,Mengjia Li,Feng Zhang,Xingbang Hu,Youting Wu
With the catalytic induction of ethylene glycol (EG), anhydrous N,N-dimethylethanolamine (DMEA) shows CO2 absorption performance via chemical binding and physical storage under normal pressure. Among the absorbents, pure DMEA and EG can hardly absorb CO2 directly, but when the zwitterionic alkylcarbonates are formed between CO2 and DMEA-EG, which can be characterized by 13C NMR and FTIR spectroscopy, the absorption rate of CO2 is improved. With the increase in the CO2 loading as the mass fraction of EG in DMEA–EG, 80 wt % EG captures up to 0.72 mol/mol at 293 K and 101 kPa via chemical binding and physical storage. The amount that is chemically bound and physically stored is directly dependent on temperature; within the range of 293–323 K, an absorption–regeneration cycle can be formed in a closed vessel because the zwitterion DMEA–EG–CO2 is unstable at higher temperatures. In other words, DMEA–EG–CO2 can be easily regenerated upon appropriate depressurization or heating. The corresponding thermodynamic calculations prove that the regenerative energy of DMEA–EG–CO2 is −27.33 kJ/mol, far less than that of other absorbent systems.
研究领域:
化学工程
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环境科学
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物理化学
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能源技术
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气体分离
✓ 已验证
DOI
高影响因子
ACS Sustainable Chemistry & Engineering
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2020
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IF 7.632
Tiantian Ping,Yu Dong,Shufeng Shen
Nonaqueous amine-based absorbents by replacing water with organic solvents have potential advantages of low energy penalty and reduced amine degradation for CO2 capture. An advanced nonaqueous system of 2-(butylamino)ethanol (BAE) with 2-butoxyethanol (EGBE) was proposed for low-energy consumption CO2 capture. EGBE was selected as a green cosolvent because of its superior properties over the reported organics and water. A comprehensive study on CO2 capture performance has been performed for secondary alkanolamine nonaqueous systems such as 2-(methylamino)ethanol (MAE), 2-(ethylamino)ethanol (EAE), and BAE and their aqueous counterparts. Product species in CO2-loaded solutions were identified by 13C nuclear magnetic resonance and Fourier transform infrared spectroscopy. Regeneration energy consumption was also evaluated using a modified method and compared with that of conventional aqueous monoethanolamine (MEA). Results demonstrated that the aqueous 5.0 M secondary amine absorbents had higher absorption capacity and larger cyclic capacity than their nonaqueous counterparts. The desorption efficiency for both systems was in a descending order: BAE > EAE > MAE. Surprisingly, the cyclic capacity of aqueous and nonaqueous BAE systems was about 180 and 100% higher than that of aqueous MEA, respectively. The underlying reasons were also discussed. CO2 can react with these amines, forming unstable carbamates and protonated amines in the EGBE solvent, whereas it forms bicarbonate species in addition to ionic couples in aqueous solutions. The regeneration heat duty of nonaqueous EGBE-based secondary amine absorbents was about 45–55% lower than that of aqueous MEA (3.82 MJ kg–1 CO2). In addition, the feasibility of low-temperature desorption makes the BAE/EGBE absorbent a compelling solution for energy-saving CO2 capture technology using low-grade industrial waste heat.
研究领域:
化学工程
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环境科学
✓ 已验证
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2020
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IF 5.065
Yu Dong,Tiantian Ping,Xiaoqin Shi,Shufeng Shen
Nonaqueous amine-based blends have great potential for energy-efficient CO 2 absorbent. In this work, densities and viscosities were measured for liquid binary mixtures of 2-(ethylamino)ethanol (EAE) and 2-(butylamino)ethanol (BAE) with 2-butoxyethanol (EGBE) at temperatures of (293.15–353.15)K over the entire concentration range and atmospheric pressure. Intermolecular interactions between EGBE and two secondary amines with different carbon chain length were discussed. The excess molar volume ( V E ), viscosity deviations ( ∆η ) and excess Gibbs free energy ( ∆G ⁎ E ) were calculated from the experimental data and also correlated with the Redlich-Kister equation to estimate the binary interaction parameters. The experimental data and the calculated from the proposed correlations for the studied binary mixtures matched well each other, with AADs within 0.01% and 1.45% for density and viscosity respectively. The variation of excess properties was also discussed in terms of intermolecular interactions. Weak interactions on mixing these binary mixtures with different mass fractions were observed from the FTIR spectra analysis.
研究领域:
化学工程
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热力学
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流体物理化学
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气体吸收
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分离科学
✓ 已验证
DOI
高影响因子
危险品化学品经营许可证（带存储）