Experimental and modeling investigation on CO2 sorption kinetics over K2CO3-modified silica aerogels

Zhao, Chuanwen; Guo, Yanxia; Li, Weiling; Bu, Changsheng; Lu, Ping

doi:10.1016/j.cej.2016.11.121

Cited by 40 publications

(22 citation statements)

References 58 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Where q e is the amount of SO 2 adsorbed at equilibrium (mg/g), q t is the amount of SO 2 adsorbed at time t (mg/g), and K 1 and K 2 are the rate constants of these two equations (33). The diagram of Log (q e -q t ) against time and the diagram of t/q t versus time was plotted to examine the pseudo-first-order and pseudo-second-order, respectively, for zeolite with and without the nanoparticles at 25°C.…”

Section: Adsorption Kineticsmentioning

confidence: 99%

Adsorption of Sulfur Dioxide on Clinoptilolite/Nano Iron Oxide and Natural Clinoptilolite

2019

View full text Add to dashboard Cite

Background: Sulfur dioxide gas is known to include pollutants that are harmful to human health and the environment. Therefore, due to the increase of industrial activities, SO2 gas pollution control is very important. Objectives: The purpose of this study was to investigate the efficiency of sulfur dioxide removal by iron oxide nanoparticles deposited on clinoptilolite zeolite. Methods: Two materials, natural clinoptilolite and clinoptilolite containing iron oxide nanoparticles, were used as adsorbents of SO2. Both materials were characterized via scanning electron microscopy imaging, infrared spectroscopy, and N2 porosimetry, along with the determination of the thermodynamic properties and kinetics of SO2 adsorption. Therefore, breakthrough experiments were carried out at different temperatures and with different contact times. Sulfur dioxide adsorption of a real sample was considered for both adsorbents. Results: The adsorption efficiency of SO2 in the synthetic and actual sample was obtained at 80.3% and 66.7%, respectively, under optimum conditions (temperature of 25°C and duration of 28.5 minutes) by modified zeolite with iron oxide nanoparticles. The removal percentage average of SO2 was also obtained in the synthetic and actual sample at 43.8% and 31.3%, respectively, by zeolite in optimum conditions (temperature of 25°C and contact time of 20.5 minutes). The adsorption of SO2 with both adsorbents followed the pseudo-second-order equation and the adsorption process was an exothermic and spontaneous process. Conclusions: The addition of these iron oxide nanoparticles had a positive impact on the surface area and on SO2 capacity.

show abstract

Section: Adsorption Kineticsmentioning

confidence: 99%

Adsorption of Sulfur Dioxide on Clinoptilolite/Nano Iron Oxide and Natural Clinoptilolite

2019

View full text Add to dashboard Cite

show abstract

“…However, they found that the sorbent showed low CO 2 -adsorption capacity (0.15 mmol•g −1 ), due to a large amount of hydrophilic group existing in commercialized silica aerogels. Therefore, in another study, they synthesized modified silica aerogels with a sol-gel method using tetraethoxysilane (TEOS) as a precursor and carried out impregnation with K 2 CO 3 , and improved the CO 2 -capture capacity to 0.53 mmol•g −1 [51].…”

Section: Amines Class Imentioning

confidence: 99%

The Importance of Precursors and Modification Groups of Aerogels in CO2 Capture

2021

View full text Add to dashboard Cite

The rapid growth of CO2 emissions in the atmosphere has attracted great attention due to the influence of the greenhouse effect. Aerogels’ application for capturing CO2 is quite promising owing to their numerous advantages, such as high porosity (~95%); these are predominantly mesoporous (20–50 nm) materials with very high surface area (>800 m2∙g−1). To increase the CO2 level of aerogels’ uptake capacity and selectivity, active materials have been investigated, such as potassium carbonate, K2CO3, amines, and ionic-liquid amino-acid moieties loaded onto the surface of aerogels. The flexibility of the composition and surface chemistry of aerogels can be modified intentionally—indeed, manipulated—for CO2 capture. Up to now, most research has focused mainly on the synthesis of amine-modified silica aerogels and the evaluation of their CO2-sorption properties. However, there is no comprehensive study focusing on the effect of different types of aerogels and modification groups on the adsorption of CO2. In this review, we present, in broad terms, the use of different precursors, as well as modification of synthesis parameters. The present review aims to consider which kind of precursors and modification groups can serve as potentially attractive molecular-design characteristics in promising materials for capturing CO2.

show abstract

“…of by-products increases and adversely affects the performance of the sorbent [19]. Also, excess water adsorption forms liquid films at the pore endings and increases the mass transfer resistance [29].…”

Section: Modelingmentioning

confidence: 99%

“…The pseudo-first order kinetic model is suitable for the diffusion-controlled adsorption processes [47]. The second-order kinetic model was proposed for the reaction-controlled adsorption processes [29]. It was reported that both models can be used to describe gas-solid kinetic performance; however, the pseudo-first order model gives accurate predictions only at the early stage of the adsorption process [29].…”

Section: Kinetic Modelmentioning

confidence: 99%

Application of Core-Shell-Structured K₂CO₃-Based Sorbents in Postcombustion CO₂ Capture: Statistical Analysis and Optimization Using Response Surface Methodology

2020

View full text Add to dashboard Cite

This study investigates the effect of core-shell-structured supports prepared with alumina as the core on the CO 2 capture performance of K 2 CO 3 . One main issue in using alumina-basedsupported K 2 CO 3 is the high moisture uptake of the sorbent, which converts active sites of K 2 CO 3 to hydrated by-products with a very low CO 2 capture capacity. To address this issue, the support was shelled with a less hydrophilic material using a core-shell technique. Six core-shell-structured supports were prepared using alumina-based cores (γ-alumina and Boehmite), and TiO 2 , ZrO 2 and SiO 2 shells. K 2 CO 3 was impregnated on each support and tested in a thermogravimetric analyzer over ten cycles. K 2 CO 3 /Boehmite/TiO 2 showed the lowest moisture uptake and the highest surface area, and thus the best CO 2 capture performance. A semi-empirical model was developed using a response surface methodology

show abstract

Experimental and modeling investigation on CO2 sorption kinetics over K2CO3-modified silica aerogels

Cited by 40 publications

References 58 publications

Adsorption of Sulfur Dioxide on Clinoptilolite/Nano Iron Oxide and Natural Clinoptilolite

Adsorption of Sulfur Dioxide on Clinoptilolite/Nano Iron Oxide and Natural Clinoptilolite

The Importance of Precursors and Modification Groups of Aerogels in CO2 Capture

Application of Core-Shell-Structured K₂CO₃-Based Sorbents in Postcombustion CO₂ Capture: Statistical Analysis and Optimization Using Response Surface Methodology

Contact Info

Product

Resources

About

Experimental and modeling investigation on CO2 sorption kinetics over K2CO3-modified silica aerogels

Cited by 40 publications

References 58 publications

Adsorption of Sulfur Dioxide on Clinoptilolite/Nano Iron Oxide and Natural Clinoptilolite

Adsorption of Sulfur Dioxide on Clinoptilolite/Nano Iron Oxide and Natural Clinoptilolite

The Importance of Precursors and Modification Groups of Aerogels in CO2 Capture

Application of Core-Shell-Structured K2CO3-Based Sorbents in Postcombustion CO2 Capture: Statistical Analysis and Optimization Using Response Surface Methodology

Contact Info

Product

Resources

About

Application of Core-Shell-Structured K₂CO₃-Based Sorbents in Postcombustion CO₂ Capture: Statistical Analysis and Optimization Using Response Surface Methodology