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

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.

Download Full-text

Effect of the Presence of Water-soluble Amines on the Carbon Dioxide (CO2) Adsorption Capacity of Amine-grafted Poly-succinimide (PSI) Adsorbent During CO2 Capture

Energy Procedia ◽

10.1016/j.egypro.2016.01.010 ◽

2016 ◽

Vol 86 ◽

pp. 90-105 ◽

Cited By ~ 9

Author(s):

Tafara Chitsiga ◽

Michael O. Daramola ◽

Nicola Wagner ◽

Jacob Ngoy

Keyword(s):

Carbon Dioxide ◽

Adsorption Capacity ◽

Co2 Capture ◽

Co2 Adsorption ◽

Water Soluble ◽

Co2 Adsorption Capacity ◽

Carbon Dioxide Co2

Download Full-text

A comparison of CO2 adsorption behaviour of mono- and diamine-functionalised adsorbents

E3S Web of Conferences ◽

10.1051/e3sconf/20199001010 ◽

2019 ◽

Vol 90 ◽

pp. 01010 ◽

Cited By ~ 3

Author(s):

Noor Ashikin Mohamad ◽

Ebrahim Abouzari Lotf ◽

M. Nasef Mohamed ◽

Ahmad Arshad ◽

TAT Abdullah

Keyword(s):

Electron Microscopy ◽

Adsorption Capacity ◽

Co2 Adsorption ◽

Morphological Changes ◽

Adsorption Behaviour ◽

X Ray Diffraction ◽

X Ray ◽

Co2 Adsorption Capacity ◽

Carbon Dioxide Co2 ◽

Scanning Electron

The paper presents a study for investigating i) the effect of amination of poly(GMA)-grafted polyethylene/polypropylene (PE/PP) substrates with trimethylamine (TMA) and ethylenediamine (EDA) and ii) their impact on carbon dioxide (CO2) adsorption capacity of the obtained adsorbents. The chemical, structural, and morphological changes of the aminated adsorbents were evaluated using Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and scanning electron microscopy (SEM), respectively. The amination yield with TMA was 40% higher than EDA. However, the obtained adsorbent showed two times lower CO2 adsorption capacity (at 30 bars) than the adsorbent with EDA and stood at 0.6 mmol g-1 compared to 1.2 mmol g-1.

Download Full-text

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.

Download Full-text

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.

Download Full-text

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

Nanomaterials ◽

10.3390/nano11102614 ◽

2021 ◽

Vol 11 (10) ◽

pp. 2614

Author(s):

Na Yang ◽

Rong Xue ◽

Guibo Huang ◽

Yunqian Ma ◽

Junya Wang

Keyword(s):

Ionic Liquid ◽

Adsorption Capacity ◽

Co2 Adsorption ◽

Imidazole Ring ◽

Bet Surface Area ◽

Adsorption Performance ◽

Adsorbent Surface ◽

Ft Ir ◽

Loading Amount ◽

Co2 Adsorption Capacity

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.

Download Full-text

Evaluation of Kaolinite and activated carbon performance for CO2 capture

10.51415/10321/3623 ◽

2021 ◽

Author(s):

◽

Stephen Okiemute Akpasi

Keyword(s):

Activated Carbon ◽

Adsorption Capacity ◽

Surface Area ◽

Co2 Capture ◽

Gas Flow ◽

Co2 Adsorption ◽

Carbon Composite ◽

Composite Adsorbent ◽

Bed Height ◽

Co2 Adsorption Capacity

Global climate change is one of the major threats facing the world today and can be due to increased atmospheric concentrations of greenhouse gases (GHGs), such as carbon dioxide (CO2). There is also an immediate need to reduce CO2 emissions, and one of the potential solutions for reducing CO2 emissions is carbon capture and storage (CCS). This work investigated the performance assessment of kaolinite and activated carbon (AC) adsorbent for CO2 capture. In particular, the effect of operating parameters such as temperature, bed height, inlet gas flow rate etc. on CO2 adsorption behaviour of the adsorbents was also investigated. Extensive research on the development of adsorbents that can adsorb large amounts of CO2 with low energy consumption has recently been carried out. In CO2 adsorption technology, the challenge is to develop an adsorbent that is not only non-toxic, eco-friendly, and cost-effective, but also has the potential to extract CO2 gas from a mixed gas stream selectively and effectively. Due to the possibility of a potential adsorbent due to its low cost, rich natural abundance and high mechanical and chemical stability, this study proposes kaolinite. As the presence of clay minerals in soils serves as a pollutant collector to enhance the atmosphere, kaolinite has the potential to be an efficient adsorbent for CO2 capture. Kaolinite was investigated as an adsorbent in this research to confirm if it is suitable for CO2 capture. Kaolinite/activated carbon composite adsorbents were synthesized. Sugarcane bagasse was used in preparing the activated carbon (AC). ZnCl2 was impregnated onto sugarcane bagasse during the preparation of activated carbon (AC) to improve the physical properties (surface area, pore size and pore volume) and the CO2 adsorption capacity of the activated carbon (AC) adsorbent developed. The materials were characterized and tested for CO2 adsorption (activated carbon and kaolinite). BET, FTIR and SEM studies were used to classify the adsorbents for their surface area and pore properties, functional groups, and surface morphology, respectively. BET analysis was conducted and the pore volume, pore size and surface area of the adsorbent materials were reported. Functional groups were actively present in the adsorption process. This was verified using FTIR spectroscopy. The kaolinite adsorbent was not feasible for CO2 capture. BET, SEM, and custom-built CO2 adsorption equipment have confirmed this. In contrast to literature, the CO2 adsorption capacity of kaolinite was low. This is due to the fact that kaolinite used in this study is not suitable as adsorbent for CO2 capture as they exhibited a low CO2 adsorption capacity. The results obtained in this study show that temperature, bed height and inlet gas flow rate influenced the adsorption behaviour of activated carbon (AC), kaolinite and kaolinite/activated carbon composite adsorbent during CO2 capture. At 30 0C, activated carbon (AC) exhibited an adsorption capacity of 28.97 mg CO2/g, the highest capacity among all the adsorbents tested. Kaolinite-activated carbon composite adsorbent offered CO2 adsorption capacities of 18.54 mg CO2/g. Kaolinite provides the lowest capacity of 12.98 mg CO2/g. In conclusion, this research verified that CO2 adsorption with kaolinite and activated carbon is favoured at low temperatures, low operating CO2 flowrates and high column bed height.

Download Full-text

Continuous Fixed Bed CO2 Adsorption: Breakthrough, Column Efficiency, Mass Transfer Zone

Processes ◽

10.3390/pr8101233 ◽

2020 ◽

Vol 8 (10) ◽

pp. 1233

Author(s):

Mohammed K. Al Mesfer ◽

Mohd Danish ◽

Mohammed Ilyas Khan ◽

Ismat Hassan Ali ◽

Mudassir Hasan ◽

...

Keyword(s):

Mass Transfer ◽

Adsorption Capacity ◽

Co2 Capture ◽

Molecular Sieve ◽

Co2 Adsorption ◽

Superficial Velocity ◽

Column Efficiency ◽

Co2 Adsorption Capacity ◽

Mass Transfer Zone ◽

Transfer Zone

The increased levels of carbon dioxide in the environment have incited the search for breakthrough technologies to lessen its impact on climate. The CO2 capture from a mixture of CO2/N2 was studied using a molecular sieve (MS) and silica gel type-III. The breakthrough behavior was predicted as a function of temperature, superficial velocity, and CO2 partial pressure. The breakpoint time reduced significantly with increased temperature and increased superficial velocity. The CO2 adsorption capacity increased appreciably with decreased temperature and increased CO2 pressure. The saturation CO2 adsorption capacity from the CO2/N2 mixture reduced appreciably with increased temperature. The molecular sieve contributed to higher adsorption capacity, and the highest CO2 uptake of 0.665 mmol/g was realized for MS. The smaller width of the mass transfer zone and higher column efficiency of 87.5% for MS signify the efficient use of the adsorbent; this lowers the regeneration cost. The findings suggest that a molecular sieve is suitable for CO2 capture due to high adsorption performance owing to better adsorption characteristic parameters.

Download Full-text

Adsorption performance of basic fuchsin on alkali-activated diatomite

Adsorption Science & Technology ◽

10.1177/0263617420922084 ◽

2020 ◽

Vol 38 (5-6) ◽

pp. 151-167 ◽

Cited By ~ 1

Author(s):

Yong-Hua Zhao ◽

Jin-Tao Geng ◽

Jie-Chuan Cai ◽

Yu-Fu Cai ◽

Chun-Yan Cao

Keyword(s):

Adsorption Capacity ◽

Adsorption Process ◽

Textural Properties ◽

Alkali Activation ◽

Maximum Adsorption Capacity ◽

Basic Fuchsin ◽

Activation Temperature ◽

X Ray ◽

Adsorption Performance ◽

Alkali Activated

The natural diatomite was treated with NaOH to obtain alkali-activated diatomite. The materials were systematically characterized by X-ray powder diffraction, X-ray fluorescence, Fourier transform infrared spectroscopic, scanning electron microscopy, and N2 adsorption–desorption. Meanwhile, the potential use of alkali-activated diatomite as adsorbent for the removal of basic fuchsin from aqueous solution was assessed by batch experiment. Results indicated that the structure and textural properties of diatomite were obviously changed via alkali activation, and then affecting its adsorption performance. The adsorption capacity of alkali-activated diatomite for basic fuchsin was higher than that of natural diatomite. In the case of alkali-activated diatomite, its adsorption capacity was increased with increasing the activation temperature, and the diatomite activated at 115°C (alkali-activated diatomite-115) exhibited the maximum adsorption capacity. The pseudo-first-order kinetics and the Sips isotherm model were preferable to describe the adsorption process of basic fuchsin on alkali-activated diatomite-115 and the thermodynamic parameters indicated that the adsorption process was endothermic and spontaneous.

Download Full-text