SEPARATION AND PURIFICATION TECHNOLOGY
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2021
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IF 7.312
Wenjie Xiong,Mingzhen Shi,Lingling Peng,Xiaomin Zhang,Xingbang Hu,Youting Wu
CO 2 and H 2 S are considered impurities in natural gas that moderate the pace of environmental health. Developing highly efficient and cost-effective absorbents is of significance for sweetening natural gas. Herein, four superbase protic ionic liquids (SPILs) were prepared in this study. Typical physical properties (density, viscosity, and decomposition temperature) were also examined at ambient pressure. These SPILs show low viscosity values at ranging from 5.1 cP to 18.3 cP at 313.2 K. The solubility of H 2 S (0–1.0 bar), CO 2 (0–1.0 bar), and CH 4 (0–5.0 bar) was systematically measured at temperatures in the range of 298.2 K to 333.2 K. Impressively, the absolute solubility of H 2 S under 0.1 bar was found to be located at 4.31–5.15 mol/kg at 313.2 K, which is the highest value obtained among the reported results in the literature. The ideal selectivity of H 2 S/CH 4 and CO 2 /CH 4 (H 2 S or CO 2 solubility at 0.1 bar vs CH 4 solubility at 1 bar) at 313.2 K are in the ranges of 367–653 and 92.4–240, respectively. The interaction mechanism we explored was characterized by NMR and FT-IR spectroscopy. Thermodynamic parameters, such as enthalpy, Gibbs free energy, and entropy of dissolution were calculated from the temperature dependent solubility using the “deactivated model”. These SPILs are promising alternative candidates for the simultaneous removal of H 2 S and CO 2 in natural gas upgrading.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2023
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IF 8.6
Peijing Shao,Yao Shen,Jiexu Ye,Jingkai Zhao,Lidong Wang,Shihan Zhang
Metal-organic frameworks (MOFs) have been extensively studied as candidate materials for enzyme immobilization over recent years. In this work, carbonic anhydrase was immobilized in ZIFs by “in situ” immobilization method. The growth state of ZIF-8 was adjusted by adjusting the ratio of Zn 2+ and 2-Hmim to obtain crystals with different morphologies (cubic-, dodecahedral- and leaf-shape). In addition, different surfactants (cationic surface-active agent, an-ionic surfactant, and non-ionic surface-active agent) were added as “shape-inducing agents” to further regulate the crystal shapes, thus affecting the activity of enzyme immobilization in ZIFs. Through CO 2 absorption test, it was found that the thick leaf-shaped CA/ZIF-L-(PVP) induced by PVP had a higher relative activity (150%) than other shapes (cubic, dodecahedral, “burr puzzle” shape, “interpenetration leaves” shape, etc.) of immobilized enzymes. In addition, CA/ZIF-L-(PVP) exhibited excellent reusability and stability, which maintained a relative activity of 131% after 5 cycles, and remained approximately 99% relative activity after 15 days at 40 °C in MDEA solution.
研究领域:
材料科学
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生物化学
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环境科学
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DOI
高影响因子
Greenhouse Gases-Science and Technology
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2022
·Vol. 12
·期 3
·362-375
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IF 2.518
Jinxiu Li,Yu Li,Chen Li,Rui Tu,Pengfei Xie,Yi He,Yao Shi
While nonaqueous organic-amine absorbents have great potential in reducing energy consumption of CO 2 capture, their absorption/desorption behaviors are still poorly understood when high-concentration polyamines are used. On the other hand, large scale CO 2 capture demands the use of high-concentration polyamines absorbents. Therefore, we investigated the absorption and microwave regeneration behavior of high-concentration triethylenetetramine (TETA) in three typical organic solvents, including polyethylene glycol 200 (PEG200), diethylene glycol (DEG), and ethylene glycol (EG). The results showed that high-concentration TETA nonaqueous absorbents demonstrate advantages in absorption rate and regeneration energy consumption. The average absorption rate of 2.0 and 5.0 mol/L TETA/EG was 2.84 and 4.70 times that of 0.6 mol/L, respectively. The energy consumption of TETA/EG and TETA/DEG decreased by 29.4 and 25.6% as the concentration increased from 0.6 to 5.0 mol/L. In addition, the high-concentration TETA/PEG200 absorbent demonstrated observable tolerance for water vapor, which usually exists in flue gas. Results also showed that microwave regeneration was superior to conventional conduction heating especially when high-concentration TETA/PEG200 absorbent were used. The energy consumption of microwave regeneration of the absorbent with a concentration of 0.6, 2.0, and 5.0 mol/L was reduced by 65.9, 81.2, and 86.0%, respectively when compared with conduction heating. © 2022 Society of Chemical Industry and John Wiley & Sons, Ltd.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
SEPARATION AND PURIFICATION TECHNOLOGY
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2022
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IF 9.136
Yun Li,Houfang Lu,Yingying Liu,Kejing Wu,Yingming Zhu,Bin Liang
Nano-SiO 2 was used to enhance the performance of CO 2 absorption and desorption in viscous DBU-glycerol solution with a viscosity of about 60 mPa·s. The effects of ultrasonic time in the preparation of nanofluids, solids loading and particle/cluster size of SiO 2 on absorbent properties and absorption performance were investigated. Meanwhile, the enhancements of heat transfer and mass transfer with nanoparticles in the desorption of CO 2 -loaded DBU-glycerol solutions were also analyzed. Proper ultrasonic vibration time and nano-SiO 2 loading can both decrease the average particle size in the system which can improve the absorption. The increase of interfacial area between gas and liquid with the addition of nano-SiO 2 dominates the enhancement of absorption and it has little effect on the enhancement factor when the nano-SiO 2 size is 102 nm or below. But when the particle size is higher than 102 nm, the enhancement factor decreases with the increase of particle/cluster size. The addition of 0.10 wt% SiO 2 nanoparticle with a particle size of 16 nm can increase the absorption rate by 31 % compared with base liquid. In desorption process, the desorption rate for CO 2 -loaded DBU-glycerol solutions can increase 18 % with the addition of 0.10 wt% nano-SiO 2 with a particle size of 32 nm. The main reason could be that nano-SiO 2 can improve the heating rate of the base fluid and supply plenty of nucleation sites for the formation of bubbles to improve the desorption rate. It shows that nano-SiO 2 can be used to enhance both the absorption and desorption processes in solutions with high viscosity.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
INDUSTRIAL & ENGINEERING CHEMISTRY RESEARCH
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2024
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IF 3.8
Zhilin Ma,Yongda Cao,Xiujun Peng,Qiulin Yang,Chao Wang,Chang-An Zhou,Lei Song,Kui Ma,Hairong Yue
The chemical absorption method using MEA has been one of the most effective CO2 capture technologies, but the problems of low process efficiency and poor economics limit its application. In this work, the rapid phase change absorbent composed of alcohol ether solvent and potassium amino acid salt (AaK) solution was investigated, and the effects of different AaKs and ethers on the phase change behavior, phase separation mechanism, and CO2 absorption performance of the absorbent were analyzed. The results showed that when the carbon chain of the linear AaK was longer, the solubility in water was larger, and the lower liquid phase (LP) volume, phase separation time, AaK enrichment in the LP, and CO2 molar loading were larger. When the alkyl group of the branched-chain AaK was larger, the solubility in water was smaller, and the gas–liquid mass transfer, enrichment effect, and absorption rate were smaller. When the ether bonds of ether solvent were greater, the solubility of organic salts and competition for water were stronger; thus, the LP volume was smaller. Moreover, the absorption rate and CO2 loading of AaK systems were affected by the spatial structure effect of amino and carboxyl groups and the viscosity effect of solvent before absorption.
研究领域:
化学工程
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环境科学
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能源技术
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产品关联
DOI
高影响因子
Greenhouse Gases-Science and Technology
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2025
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IF 2.8
Ziyong Li,Qingdan Huang,Tingyan Wang,Huihong Huang,Haoyong Song
The amino groups and its substituents of organic amine absorbents have an important influence on the CO 2 absorption and desorption performance. In this study, four diamines with the same primary amino group and another different amino groups were selected as absorbents, including 1,3-propanediamine (1,3-PDA), 3-methylaminopropylamine (MAPA), 3-dimethylaminopropylamine (DMAPA), and 3-diethylaminopropylamine (DEAPA). The phase-change absorption system uses a mixture of polyether and H 2 O as the solvent. The CO 2 absorption performance of flue gas was studied with the analysis on absorption and desorption rate, cycle capacity, and desorption ratio. The effect of diamine molecular structures on phase-change CO 2 capture was investigated by nuclear magnetic carbon spectroscopy. The results show that DEAPA exhibits highest absorption capacity of 1.21 mol CO 2 /mol amine and recycling capacity of 1.09 mol CO 2 /mol amine. The absorption rate of primary and secondary diamines in the phase-change system is significantly higher than that of primary and tertiary diamines. The diamine system with tertiary amino groups has significantly faster desorption rate, higher desorption ratio, and cycle capacity than the primary and secondary diamine systems. The intramolecular tertiary amino group is more conducive to promoting the absorption of CO 2 than the intermolecular tertiary amino group, which can increase the absorption rate of CO 2 by the primary amino group and enhance the CO 2 desorption.
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
FUEL PROCESSING TECHNOLOGY
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2019
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IF 4.507
Ke Wang,Youwei Zhao,Peter T. Clough,Pengfei Zhao,Edward J. Anthony
Structurally modified and improved NaBr-co-doped Li 4 SiO 4 ceramics were developed for CO 2 absorption in low-CO 2 -concentration atmospheres. Pure and NaCl-doped Li 4 SiO 4 ceramics were also prepared for comparison. The samples were analyzed by X-ray diffraction, Scanning Electron Microscopy, N 2 adsorption, X-ray photoelectron spectroscopy, differential scanning calorimetry , and thermogravimetric analyses (dynamic and isothermal). The sorption kinetics were obtained using a double exponential model. The results showed that both Na and Br can be introduced into the Li 4 SiO 4 structure and doped on Li and oxygen sites, respectively. The doped sample presented a Li 2 O-enriched surface, guaranteeing abundant Li O sites and are significantly different from previous anionic (CO 3 , F and Cl) doping of Li 4 SiO 4 , Br doping also generated macroporous features with small particle size, these favorable characteristics promoted the surface chemisorption kinetics. Moreover, DSC analysis confirmed the formation of the molten phases during CO 2 absorption, which helps improve the lithium diffusion kinetics . Here, 0.1 mol NaBr doping was used to reach a maximum absorption capacity (>30.0 wt%) in 15 vol% CO 2, suggesting that NaBr-doped Li 4 SiO 4 ceramics have great potential for CO 2 capture at high temperature.
研究领域:
材料科学
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环境科学
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产品关联
DOI
高影响因子
AICHE JOURNAL
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2022
·Vol. 68
·期 6
·e17628
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IF 4.167
Wenchao Zheng,Qinlan Luo,Sen Liu,Nan Wang,Xiao Luo,Hongxia Gao,Zhiwu Liang
In order to establish an accurate kinetic model for the aqueous amine blends, monoethanolamine (MEA), 2-(ethylamino) ethanol (EAE), and 3-(diethylamino)-1-propanol (3DEA1P) have been chosen as a typical CO 2 absorption trisolvents. The reaction kinetics of aqueous amine blends with carbon dioxide have been investigated first combining experiments and molecular simulations. The stopped-flow technology has been used to obtain the observed reaction rate constant of the overall reactions over the temperature range of 293 to 313 K and at different amine concentrations. A theoretical kinetic model, based on the first-principles quantum-mechanical simulations, has been put forward to interpret the reactions between CO 2 and the aqueous trisolvent amine blends systems. The proposed model, based on the zwitterion mechanism and the base-catalyzed mechanism, shows good prediction with an acceptable absolute average deviation (AAD) of 6.32%, and has been found to be satisfactory in determining the kinetics of the involved complicated reactions.
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 MOLECULAR LIQUIDS
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2024
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IF 5.3
Wentao Zheng,Jialing Chen,Yujiao Jia,Nengqi Sun,Shiping Wang,Xianku Wu,Xuehua Zhang
A series of 1,8-Diazabicyclo[5.4.0]undec-7-ene (DBU)/N-heterocyclic DESs aqueous solutions were designed and synthesized as CO 2 capture agents. They showed excellent performance in absorption capacity, especially for the low-pressure CO 2 . The CO 2 loads in the absorbents were higher than 1.0 mol/mol when the pressure was just 0.1 bar. Through a combination of 13 C NMR spectra, FT-IR spectra and absorption experiments, a novel absorption mechanism was proposed. It was the shuttling role of the carbamate generated from CO 2 and nitrogen heterocycles, along with the synergistic roles of the DBU and water, that caused the high absorption capacity of the DBU/N-heterocyclic DESs for CO 2 . Meanwhile, the thermodynamic parameters, the activation energy and the regeneration efficiency were all measured to estimate the absorption performance of the DBU/N-heterocyclic DESs aqueous solutions for low-concentration CO 2 .
研究领域:
化学
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环境科学
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产品关联
DOI
高影响因子
APPLIED ENERGY
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2019
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IF 8.426
Yao Shen,Han Chen,Junliang Wang,Shihan Zhang,Chenkai Jiang,Jiexu Ye,Lidong Wang,Jianmeng Chen
The CO 2 capture capabilities of amine-based biphasic solvents have been extensively investigated. However, the mechanism of CO 2 absorption into the biphasic solvents has not been adequately examined, even if it is very important for the solvent screening, composition optimization, efficiency improvement and heat duty reduction. In this work, a two-stage interaction mechanism is proposed through CO 2 absorption performance , 13 C nuclear magnetic resonance analysis, and quantum calculation. The experimental results and quantum calculation revealed that the shift of the absorption mechanism depended on the active amine group in the biphasic solvents. In the first stage, for a high concentration of the active amine group, a proton was transferred from zwitterion to tertiary amines with the primary amines as intermediates. The CO 2 absorption rate was controlled by reaction kinetics, which resulted in a high absorption rate and inconspicuous phase change. In the second stage, for a low concentration of the active amine group, the thermodynamics-controlled absorption rate decreased sharply (by 65.2% for 1,4-butanediamine/N,N-dimethylcyclohexylamine) because the proton transferred from zwitterion to tertiary amines directly. Kinetic analysis revealed that, with an increase in the temperature from 298 to 333 K, the reaction rate constants increased by 285–362% at the first stage. However, the equilibrium constants decreased by 17.7–21.3% at the second stage. Taking both the kinetics and energy penalty into account, the triethylenetetramine/N,N-dimethylcyclohexylamine solution with a lean loading of 0.4 mol mol −1 is promising to achieve the high absorption rate and low-energy consumption.
研究领域:
化学工程
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环境科学
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DOI
高影响因子
CHEMICAL ENGINEERING JOURNAL
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2024
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IF 13.3
Zhipeng Chen,Tao Wang,Chao Li,Mengxiang Fang,Wei Chen,Ximing Hu,Yan Shao,Zhihao Liu,Wei Zhang,Li Zhang,Wenyang Fan,Shaojuan Zeng
Lower regeneration energy and superior cyclic capacity have enabled biphasic absorbents great potential in the area of flue gas CO 2 capture. The liquid film mass transfer coefficient(k L ) is a vital parameter in the development of absorbents with efficient CO 2 absorption mass transfer performance, while the phase separation behavior of biphasic solutions could be an essential factor for the absorption mass transfer and the stability of absorber. However, systemic kinetic research towards biphasic absorbents, especially the impact of phase separation behavior, is limited. In this study, a typical amide-based biphasic absorbent diethylenetriamine(DETA)/diethanolamine(DEA)/N, N-dimethylacetamide(DMAC) which has achieved great reduction in regeneration energy, was selected as the subject of kinetic investigation in a wetted wall column. The CO 2 overall mass transfer coefficient(K G ) of DETA/DEA/DMAC exceeded other biphasic solvents, blended amine solution, and 40% K 2 CO 3 solution, with 3 times that of 40% K 2 CO 3 solution. Moreover, various operational conditions including absorption temperature, gas flow rate, and water content of solution were taken into account to build a multiple-condition kinetic mechanism to offer guidance for biphasic absorbents. Furthermore, phase separation behavior was revealed as the main blame for the deterioration in the liquid film chemical mass transfer process of biphasic solvents in the CO 2 absorption process, resulting in the k L of DETA/DEA/DMAC before phase separation decreased by 75.3% at the phase separation stage. Therefore, it is crucial to ensure that the CO 2 loading of the solution entering absorber is lower than the phase separation point in applications. After phase separation, DETA/DEA/DMAC split into the organic and aqueous phases, the k L of the aqueous phase gradually exceeded that of the organic phase as CO 2 loading increased for its higher chemical enhancement factor(E).
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
ENERGY & FUELS
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2017
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IF 3.091
Jun Cheng,Yannan Li,Leiqing Hu,Jianzhong Liu,Junhu Zhou,Kefa Cen
A phase-change solvent for CO2 absorption was prepared by mixing N-methyl-1,3-diaminopropane (MAPA) and N,N-dimethylformamide (DMF). In this MAPA/DMF solvent, MAPA-carbamate precipitate was formed after CO2 absorption to facilitate reducing energy consumption of amine regeneration. The CO2 uptake of MAPA/DMF solvent (14.8 mg/g solvent) was increased by 22% compared with that of MAPA/water solvent (12.1 mg/g solvent). For MAPA/DMF solvent, time was reduced by 22% to reach the CO2 absorption equilibrium. The maximum CO2 uptake rate of MAPA/DMF solvent was 30% higher than that of MAPA/water solvent because DMF displayed higher CO2 solubility and lower MAPA-carbamate solubility than water. Differential scanning calorimetry and thermogravimetry experiments revealed that MAPA(H+)2 and MAPA(CO2–)2 compositions in MAPA-carbamate precipitate first decomposed (peak temperature = 59.9 °C). Subsequently, the MAPACO2 compositions in precipitate also decomposed (peak temperature = 124.2 °C).
研究领域:
化学工程
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环境科学
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DOI
高影响因子
危险品化学品经营许可证（带存储）