SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Dongfang Zhao,Shoulong Dong,Liju Bai,Dongyang Li,Helei Liu
The concentration profiles of all chemicals obtained in the Amine-CO 2 -H 2 O system based on the Vapor-liquid equilibrium (VLE) plots are essential for the analysis and understanding of the kinetics. This work aims at obtaining accurate and reliable VLE plots of 3DMA1P via both experimental and mathematical methods. VLE plots are essential for understanding the reaction process and mechanism of carbon dioxide absorption into amine solutions. The experiments were conducted over a concentration range of 1 ∼ 2 mol/L, temperature of 298 K, and CO 2 partial pressure of 15 kPa. Regarding the experimental method, 13 C NMR detection was performed to generate concentrations of Amine and AmineH + based on the protonation calibration equation. The results showed that the 13 C NMR method had little difference between the results of mass conservation calculation and charge conservation calculation under different CO 2 loading. Among the mathematical methods, the results obtained by the pH method involving charge conservation were quite different from those calculated by mass conservation, while the D-M model method strictly following the theoretical system satisfied both the mass and charge conservation. The distribution curves of the concentration of each species obtained by the three methods were compared. It was found that 13 C NMR and D-M model method could secure closer and more accurate results than the pH method. In conclusion, both the 13 C NMR method and the D-M model method plots are useful for obtaining accurate and reliable VLE plots for the 3DMA1P-CO 2 -H 2 O system, as well as for other monoamine and mixed amine systems.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2019
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IF 2.298
Yibo Fang,Zanjun Gao,Kangli Bao,Jiongliang Huang,Xiaosheng Ji,Xiaohong Han,Guangming Chen
The working pairs of HFCs + organic absorption solvents are commonly used in absorption systems. In this work, the vapor–liquid equilibrium (VLE) data of HFC-32 + DMETrEG at (293.15–343.15) K and HFC-32 + NMP at (323.15–343.15) K were measured in a dual cycle apparatus. The VLE data were correlated by Antione-type equation, NRTL, and PR + MHV1 + NRTL model, respectively. The predicted VLE data showed a good agreement with the experimental VLE data. NRTL model was recommended to predict the VLE data and characteristic of solution for HFC-32 + DMETrEG and HFC-32 + NMP, compared to PR + MHV1 + NRTL model. The comparison of VLE characteristics for five binary mixtures (HFC-32 + DMETrEG, HFC-32 + NMP, HFC-32 + DMF, HFC-32 + DMAC, and HFC-32 + DMEDEG) was carried out. The compared results showed that the system pressures of HFC-32 + DMETrEG and HFC-32 + NMP were lower than other three mixtures, and the negative deviations from Raoult’s law of HFC-32 + DMETrEG and HFC-32 + NMP were larger than the others, which indicated that the two mixtures were more suitable as the working fluids for absorption system.
研究领域:
化学工程
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热力学
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DOI
高影响因子
ENERGY
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2021
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IF 7.147
Xiao Zhang,Liang Cai,Tao Chen,Jingyi Qiao,Xiaosong Zhang
This research aims to develop novel binary working pairs using low-GWP refrigerants (R32, R152a, or R161) and one chemical absorbent (DMETEG) for absorption refrigeration systems . The solubility data were determined from 293.15 to 343.15 K using a static method and were correlated with the five-parameter non-random two-liquid (NRTL) activity coefficient model with an average relative absolute error of <2.4%. All three binary mixtures exhibited negative deviations from Raoult’s law. DMETEG was further assessed with other organic solvents that were previously measured to verify its highest affinity with HFCs. Based on the obtained VLE data, the thermodynamic performances in both the single-stage absorption refrigeration system (ARS) and the absorption-compression hybrid refrigeration system (ACHRS) were assessed. R161 yielded the highest cooling COP of 0.519–0.555 when the generation temperature was above 135 °C, followed by the R152a at 0.231–0.518 when below 135 °C. Different from the trends of COP variations, R152a had the highest ECOP of 0.091–0.158 when the generation temperature was below 135 °C while R161 showed the highest ECOP of 0.116–0.137 over 135 °C. ACHRS can effectively enhance the cooling performances of ARS via compression and its compression ratios got optimized. Overall, the R161 + DMETEG showed the best potential as the working pair.
研究领域:
化学工程
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制冷技术
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产品关联
DOI
高影响因子
JOURNAL OF MOLECULAR LIQUIDS
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2023
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IF 6
Yahui Yin,Weiping Liu,Xia Li,Yu Zhou,Xianzhen Xu
The vapor–liquid equilibrium (VLE) data of amino acids holds immense importance in chemical engineering. The VLE data of L-Alanine + H 2 O, DL-Valine + H 2 O and DL-Methionine + H 2 O were measured experimentally. The feasibility of VLE data is studied by using NRTL-Xu model, and the parameters of these systems were given. Furthermore, the Fourier Transform Infrared (FTIR) spectroscopy technique was used to study the microscopic properties of the amino acid solutions. Finally, the total mean interaction energy of water in the systems was studied by COSMOthermX. The results show that the vapor pressure increases with increasing temperature in the system, the vapor pressure of the higher solubility system is lower than the low solubility system and the pure solvent. From the FTIR results, it can be seen that the greater the solubility of amino acids in water, the stronger the hydrogen bond interaction with water. Meanwhile, the results of COSMOthermX show that the total mean interaction energy in the systems is least affected by the concentration. The structure–activity relationship between macroscopic properties (VLE) and microscopic interactions (hydrogen bonds) was established.
研究领域:
化学工程
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光谱学
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计算化学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2019
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IF 5.107
Min Xiao,Ding Cui,Liangyu Zou,Qi Yang,Hongxia Gao,Zhiwu Liang
Three tertiary diamines, N , N , N' , N' -tetramethyl-1,2-ethanediamine, N , N , N ', N '- tetramethyl-1,3-propanediamine and N , N , N ', N '-tetramethyl-1,4-butanediamine, were investigated for application in post-combustion CO 2 capture. The acid-base properties of the diamines were studied through measuring pH values of the acidified amine solutions to obtain reaction constants and corresponding enthalpies/entropies of the reactions. Competitive formation of monoprotonated and diprotonated diamines was observed. CO 2 absorption using these diamine solutions was carried out through a continuous flow method. NMR spectroscopy was used to detect speciation of the bulk solution. Then a general evaluation of the diamines was made in comparison with the monoamines in terms of equilibrium CO 2 solubility and p Ka . The results demonstrated the potential of the structurally modified diamines to be promising bicarbonate forming absorbents in CO 2 absorption. Finally, the equilibrium CO 2 solubility of aqueous N , N , N' , N' -tetramethyl-1,2-ethanediamine solution was measured at a wider range of temperatures, CO 2 partial pressures and initial amine concentrations to establish a thermodynamic model. The model provided reasonable prediction of equilibrium CO 2 solubility and species concentration profiles.
研究领域:
化学工程
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环境科学
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产品关联
DOI
高影响因子
JOURNAL OF CHEMICAL THERMODYNAMICS
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2026
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IF 2.5
Kuan Ji,Yahui Yin,Xiuyu Du,Sainan Wen,Pingxiao Jia,Xianzhen Xu,Yu Zhou
The separation of isoamyl formate (IAF) and isoamyl alcohol (IA) is challenging due to the formation of an industrial azeotrope, making extractive distillation a promising alternative. In this work, 1-hexyl-2,3-dimethylimidazolium acetate ([HMMIM][OAc]) was selected as an entrainer via COSMO-RS screening. Isobaric vapor–liquid equilibrium (VLE) data for the IAF + IA binary system and the IAF + IA + [HMMIM][OAc] ternary system were measured at 101.3 kPa. The data passed the thermodynamic consistency test and were well correlated with the non-random two-liquid (NRTL) model. The minimum IL mole fraction required to break the azeotrope is 0.030. σ-Profile analysis and MD simulations revealed that [HMMIM][OAc] significantly enhances the relative volatility of IAF to IA, with improved efficiency at higher ionic liquid loadings. An extractive distillation process employing the ionic liquid for separating the IAF + IA azeotrope was simulated in Aspen Plus, and its performance was economically evaluated using the total annual cost (TAC). The optimized process achieved a minimum TAC of about 907 k$/year. These findings demonstrate that [HMMIM][OAc] is an efficient entrainer for IAF/IA separation and provide both experimental and theoretical foundations for designing processes for C5 alcohol–ester azeotropic systems.
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DOI
高影响因子
JOURNAL OF CHEMICAL AND ENGINEERING DATA
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2021
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IF 2.694
Gongran Ye,Yibo Fang,Yalun Li,Zhikai Guo,Lin Wang,Xiaohong Han
The absorption refrigeration system (ARS) was important for energy saving, which can be driven by low-grade energy. In this work, the mixtures of trans-1,3,3,3-tetrafluoropropene (R1234ze(E)) + N-methyl-2-pyrrolidone (NMP) and R1234ze(E) + triethylene glycol dimethyl ether (DMETrEG) were considered as the promising new working fluids for ARS. The vapor–liquid equilibrium (VLE) data of R1234ze(E) + DMETrEG and R1234ze(E) + NMP binary mixtures were measured using a liquid-recirculation apparatus from 293.15 to 353.15 K. The VLE data were correlated by the five-parameter non-random two-liquid activity coefficient model, and the correlated results showed a good agreement with the experimental VLE data. The average absolute relative deviation and maximum absolute relative deviation of the pressure were 1.70 and 5.11% for R1234ze(E) + NMP and 1.30 and 3.22% for R1234ze(E) + DMETrEG, respectively. The two binary mixtures exhibited positive deviations from Raoult’s law.
研究领域:
热力学
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化学工程
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制冷技术
✓ 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）