CO2 Adsorption Performance and Kinetics of Ionic Liquid-Modified Calcined Magnesite

CO2 is a major contributor to global warming, and considerable efforts have been undertaken to capture and utilise it. Herein, a nanomaterial based on ionic liquid (IL)–modified calcined magnesites was investigated for CO2 capture. The synthesised nanomaterial (magnesite modified using [APMIM]Br) exhibited the best adsorption performance of 1.34 mmol/g at 30% IL loading amount, 50 °C, 0.4 MPa and 150 mL/min. In particular, the obtained nanomaterial could be regenerated at a low temperature of 90 °C for 3 h, and its CO2 adsorption capacity of 0.81 mmol/g was retained after eight cycles. FT-IR results showed that the imidazole ring and C–N group are directly related to CO2 adsorption capacity. Moreover, improving the conjugative effect of the imidazole ring enhanced the adsorption performance. Further, CO2 was adsorbed on the adsorbent surface and incomplete desorption decreased the BET surface area and CO2 adsorption capacity. Additionally, four models were selected to fit the adsorption kinetics. The results show that the adsorption mechanism fits the pseudo-first-order model well.

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Molecular sieve supported ionic liquids as efficient adsorbent for CO2 capture

Journal of the Serbian Chemical Society ◽

10.2298/jsc220214103y ◽

2015 ◽

Vol 80 (2) ◽

pp. 265-275 ◽

Cited By ~ 9

Author(s):

Na Yang ◽

Rui Wang

Keyword(s):

Ionic Liquids ◽

Adsorption Capacity ◽

Molecular Sieves ◽

Co2 Adsorption ◽

Ft Ir ◽

Loading Amount ◽

Vacuum Heating ◽

Co2 Adsorption Capacity ◽

Supported Ionic Liquids

[NH3e-mim][BF4], [OHe-mim][BF4] and [HOEAm] were selected and supported onto molecular sieves NaY, USY, SAPO-34 and MCM-41, to prepare supported ionic liquids. It was found that [NH3e-mim][BF4]/NaY has excellent CO2 adsorption performance, with adsorption capacity of 0.108 mmolCO2/g. This paper investigates the optimal adsorption conditions and recyclability of [NH3e-mim][BF4]/NaY. The results show that [NH3e-mim][BF4]/NaY has good CO2 adsorption under the condition of 20?C and 20% ILs loading amount. By vacuum heating, CO2 adsorption capacity reaches 0.451mmolCO2/g at fifth runs and reduces to 0.29mmolCO2/g at tenth runs. The structure and characterization of the [NH3e-mim][BF4]/NaY was examined by FT-IR, XRD, SEM and TG-DSC. TG-DSC also shows that it has good thermostability below 50?C.

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Enhanced Adsorption of Carbon Dioxide from Simulated Biogas on PEI/MEA-Functionalized Silica

International Journal of Environmental Research and Public Health ◽

10.3390/ijerph17041452 ◽

2020 ◽

Vol 17 (4) ◽

pp. 1452

Author(s):

Yankun Sun ◽

Wanzhen Liu ◽

Xinzhong Wang ◽

Haiyan Yang ◽

Jun Liu

Keyword(s):

Thermal Stability ◽

Adsorption Capacity ◽

Co2 Adsorption ◽

Weight Ratio ◽

Diffusion Resistance ◽

Impregnation Method ◽

Adsorption Activity ◽

Adsorption Performance ◽

Co2 Adsorption Capacity ◽

Thermal Stability Of

A series of efficient adsorbents were prepared by a wet-impregnation method for CO2 separation from simulated biogas. A type of commercially available silica, named as FNG-II silica (FS), was selected as supports. FS was modified with a mixture of polyethyleneimine (PEI) and ethanolamine (MEA) to improve the initial CO2 adsorption capacity and thermal stability of the adsorbents. The influence of different adsorbents on CO2 adsorption performance was investigated by breakthrough experiments. Scanning electron microscopy (SEM), fourier transform infrared spectroscopy (FTIR), and N2 adsorption–desorption isotherm were used to characterize the silica before and after impregnating amine. Additionally, the thermal stability of adsorbents was measured by differential thermal analysis (TDA). Silica impregnated with mixtures of MEA and PEI showed increased CO2 adsorption performance and high thermal stability compared with those obtained from silica impregnated solely with MEA or PEI. With a simulated biogas flow rate of 100 mL/min at 0.2 MPa and 25 °C, FS-10%MEA-10%PEI exhibited a CO2 adsorption capacity of ca. 64.68 mg/g which increased by 81 % in comparison to FS-20%PEI. The thermal stability of FS-10%MEA-10%PEI was evidently higher than that of FS-20%MEA, and a further improvement of thermal stability was achieved with the increasing value of PEI/MEA weight ratio. It was showed that MEA was able to impose a synergistic effect on the dispersion of PEI in the support, reduce the CO2 diffusion resistance and thus increase CO2 adsorption performance. Additionally, if the total percentage of amine was the same, FS impregnated by different ratios of PEI to MEA did not exhibit an obvious difference in CO2 adsorption performance. FS-15%PEI-5%MEA could be regenerated under mild conditions without obvious loss of CO2 adsorption activity.

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Optimized Preparation of Nanosized Hollow SSZ-13 Molecular Sieves with Ultrasonic Assistance

Nanomaterials ◽

10.3390/nano10112298 ◽

2020 ◽

Vol 10 (11) ◽

pp. 2298

Author(s):

Liang Zhou ◽

Runlin Han ◽

Yuxuan Tao ◽

Jinqu Wang ◽

Yiwei Luo

Keyword(s):

Adsorption Capacity ◽

Molecular Sieves ◽

Molecular Sieve ◽

Co2 Adsorption ◽

Hollow Structure ◽

Preparation Time ◽

Cubic Crystal ◽

Adsorption Performance ◽

Ultrasonic Time ◽

Co2 Adsorption Capacity

Because of its unique eight-membered ring pore structure and the arrangement of cations in its structure, the SSZ-13 molecular sieve has a higher affinity for CO2 than other gases, meaning it has attracted more attention than other porous materials for CO2 adsorption. However, the expensive template and long preparation time limits the industrial production of SSZ-13. In this work, a hollow structure was successfully introduced into the nanosized SSZ-13 molecular sieve with ultrasonic treatment. The effects of the amount of seed added and the ultrasonic time on the structure were investigated. When the amount of seed added was 0.5 wt.% and the ultrasonic time was 60 min, the sample showed a hollow cubic crystal with a diameter of about 50 nm. The specific surface area reached 791.50 m2/g, and the mesoporous ratio was 66.3%. The samples were tested for CO2 adsorption performance at 298 K. It was found that the hollow sample prepared in this work has higher CO2 adsorption capacity compared with the SSZ-13 zeolite prepared with conventional methods. When the adsorption pressure was 0.27 bar, the adsorption amount reached 2.53 mmol/g. The hollow SSZ-13 molecular sieve reached a CO2 adsorption capacity of 4.24 mmol/g at 1 bar.

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Synergistic Enhancement of CO2 Adsorption Capacity and Kinetics in Triethylenetetrammonium Nitrate Protic Ionic Liquid Functionalized SBA-15

Energy & Fuels ◽

10.1021/acs.energyfuels.9b01872 ◽

2019 ◽

Vol 33 (9) ◽

pp. 8967-8975 ◽

Cited By ~ 7

Author(s):

Wei Zhang ◽

Erhao Gao ◽

Yu Li ◽

Matthew T. Bernards ◽

Younan Li ◽

...

Keyword(s):

Ionic Liquid ◽

Adsorption Capacity ◽

Co2 Adsorption ◽

Protic Ionic Liquid ◽

Synergistic Enhancement ◽

Co2 Adsorption Capacity

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Development of Rubber Seed Shell–Activated Carbon Using Impregnated Pyridinium-Based Ionic Liquid for Enhanced CO2 Adsorption

Processes ◽

10.3390/pr9071161 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1161

Author(s):

Nawwarah Mokti ◽

Azry Borhan ◽

Siti Zaine ◽

Hayyiratul Mohd Zaid

Keyword(s):

Ionic Liquid ◽

Activated Carbon ◽

Adsorption Capacity ◽

Co2 Adsorption ◽

Chemical Activation ◽

Total Pore Volume ◽

Isosteric Heat ◽

Rubber Seed ◽

Study Results ◽

Co2 Adsorption Capacity

In this study, rubber seed shell was used for the production of activated carbon by chemical activation using an ionic liquid, [C4Py][Tf2N] as an activating agent. Sample RSS-IL 800 shows the highest specific surface area of 393.99 m2/g, a total pore volume of 0.206 cm3/g, and a micropore volume of 0.172 cm3/g. The performance of AC samples as an adsorbent for CO2 was also studied using a static volumetric technique evaluated at a temperature of 25 °C and 1 bar pressure. The CO2 adsorption capacity for sample RSS-IL 800 was 2.436 mmol/g, comparable with reported data from the previous study. Results also show that the CO2 adsorption capacity decreased at a higher temperature between 50 and 100 °C and increased at elevated pressure due to its exothermic behavior. The Langmuir model fits the adsorption data well, and the isosteric heat of adsorption proved that the physisorption process and exothermic behavior occur.

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K2CO3-Impregnated Al/Si Aerogel Prepared by Ambient Pressure Drying for CO2 Capture: Synthesis, Characterization and Adsorption Characteristics

Materials ◽

10.3390/ma13173741 ◽

2020 ◽

Vol 13 (17) ◽

pp. 3741

Author(s):

Yanlin Wang ◽

Baihe Guo ◽

Jingnan Guo ◽

Man Zhang ◽

Hairui Yang ◽

...

Keyword(s):

Adsorption Capacity ◽

Co2 Capture ◽

Adsorption Process ◽

Co2 Adsorption ◽

Ambient Pressure ◽

Ambient Pressure Drying ◽

Fixed Bed Reactor ◽

X Ray ◽

Adsorption Performance ◽

Co2 Adsorption Capacity

A new potassium-based adsorbent for CO2 capture with Al aerogel used as support is proposed in this work. The adsorbents with different surface modifiers (tetraethyl orthosilicate (TEOS) and trimethyl chlorosilane (TMCS)) and different K2CO3 loadings (10%, 20%, 30% and 40%) were prepared by sol-gel and iso-volume impregnation processes with ambient pressure drying. The CO2 adsorption performance of the adsorbents were tested by a fixed-bed reactor, and their adsorption mechanisms were studied by scanning electron microscopy (SEM), Brunauer Emmett Teller (BET), X-ray diffraction (XRD), Fourier transform infrared (FT-IR) spectroscopy, and X-ray fluorescence spectrometry (XRF). Furthermore, the adsorption kinetics and the cycling performance were investigated. The results show that using TEOS to modify the wet gel can introduce SiO2 to increase the strength of the skeleton. On the basis of TEOS modification, TMCS can further modify –OH, thus effectively avoiding the destruction of aerogel structure during ambient drying and K2CO3 impregnation. In this work, the specific surface area and specific pore volume of Al aerogel modified by TEOS + TMCS are up to 635.32 cm2/g and 2.43 cm3/g, respectively. The aerogels without modification (Al-B), TEOS modification (Al/Si) and TEOS + TMCS modification (Al/Si-TMCS) showed the best CO2 adsorption performance at 20%, 30% and 30% K2CO3 loading, respectively. In particular, the CO2 adsorption capacity and K2CO3 utilization rate of Al/Si-TMCS-30K are as high as 2.36 mmol/g and 93.2% at 70 degrees Celsius (°C). Avrami’s fractional order kinetic model can well fit the CO2 adsorption process of potassium-based adsorbents. Al-B-20K has a higher apparent activation energy and a lower adsorption rate during the adsorption process. After 15 adsorption-regeneration cycles, Al/Si-TMCS-30K maintain a stable CO2 adsorption capacity and framework structure, while the microstructure of Al/Si-30K is destroyed, resulting in a decrease in its adsorption capacity by nearly 30%. This work provides key data for the application of Al aerogel in the field of potassium-based adsorbent for CO2 capture.

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A Novel One-Dimensional Porphyrin-Based Covalent Organic Framework

Molecules ◽

10.3390/molecules24183361 ◽

2019 ◽

Vol 24 (18) ◽

pp. 3361

Author(s):

Miao Zhang ◽

Ruijin Zheng ◽

Ying Ma ◽

Ruiping Chen ◽

Xun Sun ◽

...

Keyword(s):

Pore Size ◽

Adsorption Capacity ◽

Surface Area ◽

Building Block ◽

Co2 Adsorption ◽

Bet Surface Area ◽

One Dimensional ◽

Covalent Organic Framework ◽

Co2 Adsorption Capacity ◽

Organic Framework

A novel one-dimensional covalent organic framework (COF-K) was firstly designed and synthesized through a Schiff-based reaction from a porphyrin building block and a nonlinear right-angle building block. The COF-K exhibited high BET surface area and narrow pore size of 1.25 nm and gave a CO2 adsorption capacity of 89 mg g−1 at 273K and 1bar.

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Study on the Compatibility of Gas Adsorbents Used in a New Insulating Gas Mixture C4F7N/CO2

Processes ◽

10.3390/pr7100698 ◽

2019 ◽

Vol 7 (10) ◽

pp. 698 ◽

Cited By ~ 2

Author(s):

Huang ◽

Wang ◽

Liu ◽

Zhang ◽

Zeng

Keyword(s):

Adsorption Capacity ◽

Molecular Sieves ◽

Co2 Adsorption ◽

High Adsorption ◽

Environment Friendly ◽

Adsorption Performance ◽

Co2 Adsorption Capacity ◽

Liquefaction Temperature ◽

Electricity Transfer

An environment-friendly insulating gas, perfluoroisobutyronitrile (C4F7N), has been developed recent years. Due to its relatively high liquefaction temperature (around −4.7 °C), buffer gases, such as CO2 and N2, are usually mixed with C4F7N to increase the pressure of the filled insulating medium. During these processes, the insulating gases may be contaminated with micro-water, and the mixture of H2O with C4F7N could produce HF under breakdown voltage condition, which is harmful to the gas insulated electricity transfer equipment. Therefore, removal of H2O and HF in situ from the gas insulated electricity transfer equipment is significant to its operation security. The adsorbents with the ability to remove H2O but without obvious C4F7N/CO2 adsorption capacity are essential to be used in this system. In this work, a series of industrial adsorbents and desiccants were tested for their compatibility with C4F7N/CO2. Pulse adsorption tests were conducted to evaluate the adsorption performance of these adsorbents and desiccants on C4F7N and CO2. The 5A molecular sieve showed high adsorption of C4F7N (22.82 mL/g) and CO2 (43.86 mL/g); F-03 did not show adsorption capacity with C4F7N, however, it adsorbed CO2 (26.2 mL/g) clearly. Some other HF adsorbents, including NaF, CaF2, MgF2, Al(OH)3, and some desiccants including CaCl2, Na2SO4, MgSO4 were tested for their compatibility with C4F7N and CO2, and they showed negligible adsorption capacity on C4F7N and CO2. The results suggested that these adsorbents used in the gas insulated electricity transfer equipment filled with SF6 (mainly 5A and F-03 molecular sieves) are not suitable anymore. The results of this work suggest that it is a good strategy to use a mixture of desiccants and HF adsorbents as new adsorbents in the equipment filled with C4F7N/CO2.

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