SEPARATION AND PURIFICATION TECHNOLOGY
·
2024
·
IF 8.1
Zhilv Chen,Tao Wang,Chao Li,Mengxiang Fang,Wei Chen,Ximing Hu,Wei Zhang,li Zhang,Wenyang Fan,Shaojuan Zeng
In recent years, a large number of studies have shown that amine based water-lean absorbents formed by amines and organic solvents exhibit high capture efficiency and low regeneration energy consumption in CO 2 capture. However, there is a lack of research that combines molecular level structure with macroscopic properties. In order to optimize the performance of amine based homogeneous water-lean absorbents by utilizing the properties of organic solvents, and to explore the correlation between the macroscopic properties of the absorbents (CO 2 capacity, removal efficiency, regeneration rate, regeneration efficiency, etc.) and the molecular structure of the absorbent components. We used experiments and molecular dynamics to study the linear terminal diamine DMEDA and non-proton polar solvent (DMF, DMPA, NMP, SFL, DMSO) system. It was found that the absorption and desorption performance of water-lean solvents was higher than that of aqueous solutions 30 wt% MEA and 30 wt% DMEDA, among which EFH with DMF as the solvent has better comprehensive performance. The molecular dynamics simulation was built to describe the solution structures of these absorbents. Through RDF calculations, the unique behavior of DMEDA in non-proton polar solvent was revealed on molecular level, it was found that organic solvents tend to aggregate with DMEDA molecules to form large molecular clusters, while CO 2 molecules may diffuse through ordered pore structures, resulting in a significant improvement in the capture performance. And it was found that there is a quantitative relationship between the intensity of intermolecular interaction between DMEDA and CO 2 and the removal efficiency change in DMEDA water-lean absorbents. A functional relationship was fitted, and a preliminary and rapid method for determining capture performance through molecular dynamics was proposed.
研究领域:
化学工程
·
环境科学
·
分子模拟
✓ 已验证
产品关联
DOI
高影响因子
MOLECULES
·
2024
·Vol. 29
·期 3
·640
·
IF 4.2
Maoqing Chai,Guangqiang Xu,Rulin Yang,Hongguang Sun,Qinggang Wang
The accumulation of waste plastics has a severe impact on the environment, and therefore, the development of efficient chemical recycling methods has become an extremely important task. In this regard, a new strategy of degradation product-promoted depolymerization process was proposed. UsingN,N′-dimethyl-ethylenediamine (DMEDA) as a depolymerization reagent, an efficient chemical recycling of poly(bisphenol A carbonate) (BPA-PC or PC) material was achieved under mild conditions. The degradation product 1,3-dimethyl-2-imidazolidinone (DMI) was proven to be a critical factor in facilitating the depolymerization process. This strategy does not require catalysts or auxiliary solvents, making it a truly green process. This method improves the recycling efficiency of PC and promotes the development of plastic reutilization.
研究领域:
材料科学
·
环境科学
✓ 已验证
产品关联
DOI
PubMed
高影响因子
CHEMICAL ENGINEERING JOURNAL
·
2025
·
IF 13.2
Zhilv Chen,Chaoming Jian,Chao Li,Tao Wang,Qinhui Wang,Mengxiang Fang,Fanpeng Meng,Wei Chen,Yongsheng An,Ximing Hu
Traditional aqueous amine-based absorbents face high energy consumption challenges in CO₂ capture processes. Replacing water with organic solvents of low viscosity, low specific heat, and high boiling point in amine-based CO₂ absorbents can effectively reduce the sensible and latent heat required for solvent regeneration. However, the introduction of organic solvents significantly alters mass transfer kinetics and chemical equilibrium, and the quantitative relationship between these effects remains unclear. In this study, water-lean absorbents EFH series with varying organic solvent concentrations were formulated using N , N -dimethyl-1,2-ethanediamine(DMEDA), N , N -dimethylformamide (DMF), and water. Kinetic parameters were measured for DMEDA aqueous solutions, MEA aqueous solutions, pure DMF, and the EFH series. The results revealed an inconsistency between the liquid film mass transfer coefficient ( kₗ ) and viscosity trends, indicating that physical mass transfer dominates the efficiency limitation of DMEDA absorbents under low CO₂ loading, while DMEDA retains sufficiently rapid chemical reaction rates even in water-lean environments. 13 C NMR analysis demonstrated that carbamate species exist as incompletely dissociated ion pairs in aprotic solvent environments. The stabilization of these ion pairs by organic solvents suppresses the generation of neutral carbamic acid, thereby restricting mass transfer and leading to an inflection point in the absorption rate. These findings highlight a dual strategy for optimizing water-lean absorbents: (1) prioritizing low-viscosity, high-CO₂-solubility solvents to enhance initial mass transfer, and (2) tuning solvent polarity or introducing proton donors to sustain reaction efficiency at higher CO₂ loadings. This work provides quantitative mechanistic insights into balancing the trade-off between chemical equilibrium and mass transfer in non-aqueous systems, offering guidance for designing energy-efficient carbon capture solvents.
✓ 已验证
产品关联
DOI
高影响因子
DESALINATION
·
2022
·
IF 11.211
Shao-Lu Li,Juntao Wang,Yaxu Guan,Junping Miao,Runsha Zhai,Jindi Wu,Yunxia Hu
Membrane fouling is the major obstacle to hinder the extensive application of polyamide thin-film composite reverse osmosis (PA TFC RO) membranes in the water purification and reclamation fields. In this study, a series of hydrophilic and charge-tuned antifouling RO membranes were fabricated by grafting three kinds of small molecules of multi-grade amines N , N -dimethylethylenediamine (DMEDA), (2-aminoethyl) guanidine (AEGu) and (2-aminoethyl)triethylenediamine (AEDABCO) via layer-by-layer interfacial polymerization (LbL-IP). Detailed characterizations revealed that the three tailored membranes presented obviously diminished surface negative charge and reduced PA layer thickness, the water permeability increased by 67.4 %, 34.7 % and 75.6 % compared to the pristine membrane , reached 4.05 L m −2 h −1 bar −1 , 3.26 L m −2 h −1 bar −1 , and 4.28 L m −2 h −1 bar −1 , respectively, meanwhile kept high NaCl rejection > 98.5 %. The dynamic fouling tests indicated that the tailored membranes exhibited much improved antifouling performance towards most of the model organic foulants. Meanwhile the membranes assembled with cationic groups exhibited an enhanced antibacterial property against E. coli . These functional small charged molecules and the convenient modification method provide a valuable pattern for designing antifouling PA TFC RO membranes, which is important for sustainable water purification.
研究领域:
材料科学
·
环境工程
·
水处理
✓ 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）