Surface modification of a low cost bentonite for post-combustion CO2 capture

doi:10.1016/j.apsusc.2013.07.005

Applied Surface Science

Volume 283, 15 October 2013, Pages 699-704

https://doi.org/10.1016/j.apsusc.2013.07.005 Get rights and content

Highlights

•
The CO₂ uptake of bentonite improved significantly after amine modification.
•
PEI-modified bentonite showed high CO₂ capture selectivity over N₂.
•
PEI-modified bentonite was stable in cyclic CO₂ adsorption–desorption runs.

Abstract

A low cost bentonite was modified with PEI (polyethylenimine) through a physical impregnation method. Bentonite in its natural state and after amine modification were characterized by scanning electron microscopy-energy dispersive X-ray spectroscopy, X-ray diffraction, N₂ adsorption–desorption isotherms, and investigated for CO₂ capture using a thermogravimetric analysis unit connected to a flow panel. The effect of adsorption temperature, PEI loading and CO₂ partial pressure on the CO₂ capture performance of the PEI-modified bentonite was examined. A cyclic CO₂ adsorption–desorption test was also carried out to assess the stability of PEI-modified bentonite as a CO₂ adsorbent. Bentonite in its natural state showed negligible CO₂ uptake. After amine modification, the CO₂ uptake increased significantly due to CO₂ capture by amine species introduced via chemisorption. The PEI-modified bentonites showed high CO₂ capture selectivity over N₂, and exhibited excellent stability in cyclic CO₂ adsorption–desorption runs.

Introduction

The increased CO₂ emission into the earth's atmosphere has raised serious concerns regarding global warming [1], and considerable effort has been made over the last decade to develop carbon capture and storage (CCS) technologies to reduce the CO₂ levels. Currently, the large-scale separation of CO₂ by liquid phase amine-based absorption is in operation throughout the world. However, they suffer a number of drawbacks, including the requirement for a large amount of energy for solvent regeneration, solvent degradation in the presence of oxygen, and equipment corrosion [2]. Compared to absorption based on aqueous amine and ammonia, adsorption is considered to be more promising for capturing CO₂ from flue gases, offering possible energy savings. Currently, both physical and chemical adsorption processes based on solid adsorbents, such as zeolites [3], [4], [5], [6], porous carbon [7], [8], [9], [10], [11], alumina [12], metal organic frameworks (MOFs) [13], [14], [15], [16], basic oxide and hydrotalcite materials [17], [18], [19], [20], [21] and functionalized nanoporous materials [22], [23], [24], [25], [26], [27], [28], [29], are being actively investigated.

Saving materials and energy has always been an important concern for industries. From this perspective, it is imperative to develop low cost and efficient solid materials for CO₂ capture. In this study, a CO₂ adsorbent based on a mineral bentonite was proposed. Bentonite has been investigated for a wide range of industrial applications owing to its specific physical and chemical properties, as well as its abundance in most continents of the world and low cost [30]. Bentonite has been studied as an adsorbent for contaminants such as heavy metals [31] or phenolic compounds [32] in waste water. Owning to its porous nature, bentonite can incorporate functionalities to form composite material for adsorption, catalysis and separations. Tomul, for example, reported adsorption and catalytic properties of bentonites pillared with iron (Fe), chromium (Cr) and iron/chromium pillars with different Fe/Cr molar ratios [33]. However, there have been only very few reports on the application of bentonite for CO₂ capture. Venaruzzo et al. [34] reported CO₂ adsorption by bentonite clay materials in both their natural state and after acid treatments and Azzouz et al. [35] examined CO₂ capture by montmorillonite (a purified bentonite) intercalated with polyol dendrimers.

In this report, a bentonite was modified with PEI (polyethylenimine) using a physical impregnation method and the resulting hybrid material was examined as an adsorbent for CO₂. Several groups have previously reported that PEI-modified mesoporous silicas are highly effective for CO₂ capture [22], [23], [24]. Since these mesoporous silica materials must be prepared using pure chemicals in the presence of a costly surfactant template that needs to be removed by calcination afterward [36], [37], we seek to study bentonite as a support material for PEI to form a hybrid CO₂ adsorbent; bentonite is easily available at low cost and does not require any particular pretreatment to use it as a support. Herein, after preparing and characterizing bentonites with different PEI loadings, their ability to capture CO₂ under different operating conditions as well as their stability in cyclic CO₂ adsorption–desorption runs were investigated.

Section snippets

Materials and PEI-impregnation on bentonite

The bentonite clay mineral was obtained from Xinyang, Henan province, PR China. Bentonite was pretreated at 150 °C in a vacuum before the N₂ adsorption–desorption measurement and amine impregnation. Zeolite 13X, activated carbon (Darco G-60, 100 mesh) and ZIF-8 were purchased from Sigma–Aldrich for comparison as an adsorbent for CO₂.

PEI was introduced to bentonite using the procedure reported by Xu et al. [22]. In a typical preparation, PEI (Aldrich, average molecular weight of 600 by GPC,

Characterization

Fig. 2 shows a scanning electron microscopy (SEM) image and EDX analysis results of the bentonite clay mineral. The chemical composition revealed atomic percentages of 73.93 (O), 20.6 (Si), 3.75 (Al), 1.21 (Mg), 0.35 (Ca) and 0.15 (Fe), indicating silica and alumina as the major constituents of bentonite, along with traces of iron, magnesium and calcium oxides [34]. Fig. 3 shows the XRD patterns of bentonite before and after PEI incorporation. The XRD pattern of bentonite revealed the

Conclusions

A low cost bentonite was modified by PEI (polyethylenimine) through a physical impregnation method. Bentonite in its natural state exhibited negligible CO₂ uptake due to weak physical adsorption by surface. After surface modification by PEI, the CO₂ uptake increased significantly, where CO₂ was captured primarily by introduced amine species through a chemisorption process. Owing to smaller pore volume, the CO₂ uptake of PEI-modified bentonite was lower than those usually achieved by

Acknowledgement

This work was supported by Plasma Research Center at Inha University, Korea (2012).

References (38)

J.D. Figueroa et al.
Advances in CO₂ capture technology—the U.S. Department of energy's carbon sequestration program
International Journal of Greenhouse Gas Control
(2008)
K.S. Walton et al.
CO₂ adsorption in Y and X zeolites modified by alkali metal cation exchange
Microporous and Mesoporous Materials
(2006)
S.T. Yang et al.
CO₂ adsorption over ion-exchanged zeolite beta with alkali and alkaline earth metal ions
Microporous and Mesoporous Materials
(2010)
C. Chen et al.
Efficient carbon dioxide capture over a nitrogen-rich carbon having a hierarchical micro-mesopore structure
Fuel
(2012)
M.G. Plaza et al.
CO₂ capture by adsorption with nitrogen enriched carbons
Fuel
(2007)
C. Chen et al.
CO₂ capture using mesoporous alumina prepared by a sol–gel process
Chemical Engineering Journal
(2011)
C.M. Lu et al.
Microwave enhanced synthesis of MOF-5 and its CO₂ capture ability at moderate temperatures across multiple capture and release cycles
Chemical Engineering Journal
(2010)
C. Chen et al.
Carbon dioxide adsorption over zeolite-like metal organic frameworks (ZMOFs) having a sod topology: Structure and ion-exchange effect
Chemical Engineering Journal
(2011)
Y. Ding et al.
Equilibria and kinetics of CO₂ adsorption on hydrotalcite adsorbent
Chemical Engineering Science
(2000)
N.H. Florin et al.
Reactivity of CaO derived from nano-sized CaCO₃ particles through multiple CO₂ capture-and-release cycles
Chemical Engineering Science
(2009)

C. Chen et al.

Calcium oxide as high temperature CO₂ sorbent: effect of textural properties

Materials Letters

(2012)

X. Xu et al.

Preparation and characterization of novel CO₂ “molecular basket” adsorbents based on polymer-modified mesoporous molecular sieve MCM-41

Microporous and Mesoporous Materials

(2003)

R. Sanz et al.

CO₂ adsorption on branched polyethyleneimine-impregnated mesoporous silica SBA-15

Applied Surface Science

(2010)

G. Christidis

Physical and chemical properties of some bentonite deposits of Kimolos Island, Greece

Applied Clay Science

(1998)

G. Bereket et al.

Removal of Pb(II), Cd(II), Cu(II), and Zn(II) from aqueous solutions by adsorption on bentonite

Journal of Colloid and Interface Science

(1997)

F.A. Banat et al.

Adsorption of phenol by bentonite

Environmental Pollution

(2000)

F. Tomul

Adsorption and catalytic properties of Fe/Cr-pillared bentonites

Chemical Engineering Journal

(2012)

J.L. Venaruzzo et al.

Modified bentonitic clay minerals as adsorbents of CO, CO₂ and SO₂ gases

Microporous and Mesoporous Materials

(2002)

A. Azzouz et al.

Carbon dioxide retention over montmorillonite–dendrimer materials

Applied Clay Science

(2010)

Cited by (55)

Increased CO<inf>2</inf> capture capacity via amino-bifunctionalized halloysite nanotubes adsorbents
2024, Fuel
The development of highly efficient and low cost CO₂ adsorbent becomes increasingly significant in order to achieve the goal of carbon neutrality. Herein we prepared a new type of 3-aminopropyltriethoxysilane (AP) and polyethyleneimine (PEI) amino-bifunctionalized adsorbent by grafting AP onto the acid thermally activated Halloysite nanotubes (HNTS) through the use of Si-OH. The results showed that the adsorption capacity of the CO₂ adsorbent (5-700-HNTS-20AP-40PEI) was 1.03 mmol/g at 50 °C and further increased to 1.51 mmol/g at 80 °C. The hydrogen bonding and dipole interactions between the amino groups in PEI and the hydroxyl and amino groups in AP promote the dispersion of PEI into pore channels of the carrier, thus reducing the aggregation and blockage. Moreover, the amino-bifunctionalized adsorbent exhibited satisfactory cyclic regenerability over 20 cycles. The analysis of adsorption kinetics and internal diffusion indicates that untreated HNTS is predominantly dominated by physisorption, whereas amino-modified solid adsorbents exhibit both physisorption and chemisorption with adsorption mainly occurring on the carrier surface.
Enhanced CO<inf>2</inf> adsorption of PEHA/sepiolite adsorbent by zirconium accelerator in post-combustion
2023, Separation and Purification Technology
The most promising approach to tackling the greenhouse gases is CO₂ capture and storage (CCS), and amine solid adsorbents are the most widely investigated materials. In this work, Zr species as an accelerator promote CO₂ adsorption of the Pentatethylenehexamine (PEHA)/sepiolite (SEP) adsorbents. The adsorption rate, CO₂ adsorption capacity, and amine efficiency were significantly improved under various conditions (temperature, gas flow, and CO₂ concentration) by the introduction of the optimal content of Zr, the optimal HSEP-Zr_0.13-PEHA_0.5-600 adsorbent exhibited 1.80 mmol/g at 60 °C. Adsorption experiments combine with characterization (TG, XPS, NH₃-TPD, SEM and TEM) exhibited that the introduction of Zr species were high dispersion on sepiolite, and Zr-O bond was formed in the structure of sepiolite. The acidity of the sepiolite supporter was enhanced by Zr which is benefit for amine loading. Above all resulted in the regeneration and thermal stability of the adsorbent were improved together. The economic evaluation results demonstrated that the adsorbent with Zr species is low-cost for large-scale post-combustion CO₂ capture.
Research progress of clay minerals in carbon dioxide capture
2022, Renewable and Sustainable Energy Reviews
CO₂ capture and storage technologies are the most effective means of reducing CO₂ concentration in the atmosphere. Natural clay minerals possess a large specific surface area and remarkable adsorption capability but meanwhile at a very low cost, remain one of the best candidates for environmental materials. They are widely used in three of the most popular capture methods: adsorption, absorption, and membrane separation. This review focuses on the application of clay minerals in the CO₂ capture processes, comprehensively summarizes the CO₂ capture capacity of different materials involved in clay minerals and the corresponding mechanism, critically evaluates the corresponding advantages and disadvantages, and discusses the challenges and prospects of clay minerals in CO₂ capture in the future. More importantly, the influence of the presence of CO₂ on clay minerals is also described, which can help to predict the possible process of geological storage after capture. Very recently, the concept of “carbon neutrality” has been put forward by the international community and received more attention, it is believed that this timely review will not only deliver readers with an insightful understanding of clay-based environmental carbon capture materials, but also provide critical guidance for “carbon neutral” from a mineralogical perspective.
Complexant-montmorillonite nanocomposites for heavy metal binding in sulfide tailing
2022, Journal of Materials Research and Technology
Citation Excerpt :
As well as Table 1 displayed specific surface area, total pore volume, micro pore volume and average pore diameter. As can be seen from Fig. 3, the pores of montmorillonites were mainly mesoporous [40], thus montmorillonites could be determined as mesoporous material. At the same time, the average pore diameter of montmorillonites in Table 1 were all between 2 and 50 nm, which strongly proved that point.
Complexant-montmorillonite nanocomposites were successfully prepared through the intercalation of the complexants cysteamine hydrochloride (CSH), 1,6-diaminlhexane (DA), tetraethylenepentamine (TEPA) with different functional group and molecular weight in this work. More importantly, it was proved that the heavy metal stabilization property of montmorillonite improved significantly after intercalation of complexants through characterization by XRD and SEM-EDS. Here, the complexant-montmorillonite nanocomposites exhibited strong pH buffering effects. The Zn stabilization rate was prone to 100% by adding DA or TEPA modified montmorillonite (DA-Mt or TEPA-Mt) into the tailings, and the releasing rate of As and Mn from tailings also decreased greatly. Generally, the Zn, Pb, Mn and As stabilization effects of both TEPA-Mt and DA-Mt were much better than that of CSH modified montmorillonite, which suggested that the heavy metal complexing abilities of complexant-montmorillonite nanocomposites highly depended on the functional group and molecular weight of the complexants. In this study, electrostatic adsorption, physical adsorption, ion exchange and complexation worked together and produced good heavy metal stabilization effect. Our findings could provide an important reference for the synthesis of efficient stabilization nanomaterials.
Adsorption studies of carbon dioxide and anionic dye on green adsorbent
2022, Journal of Molecular Structure
As a consequence of the use of obsolete coal and oil and manufacturing techniques, pollution levels are rising, posing a significant threat to the environment and public health. As a result, nearby is a pressing essential to investigate actual CO₂ emission and dye removal controls. Though, the achievement of this approach dependent particular on the use of low-cost adsorbent with high CO₂ discrimination and high adsorption bulk. In this study, date seed active carbon (DSAC) for capturing CO₂ was made using a two-step technique with KOH as the activation and varied carbonization rates. The properties of surface area on carbonization rate were investigated. The DSAC was subjected to BET, XRD, IR, and SEM examination. The researchers discovered that the micro-porous geometry has a significant impact on the adsorption efficiency of DSAC. The greatest CO₂ adsorption of 3.7 mmol/g was attained under optimal circumstances of calcination temperature 700 °C, adsorption temperature 0 °C, and pressure 1 bar. Furthermore, activated carbon with a carbonization temperature of 700 °C has a high selectivity for CO₂ over N₂, indicating that it has a promising future in CO₂ capture applications. Langmuir, Henry, Temkin, Toth, Dubbin, Harkin-Jura, Redlich Peterson, Elovich, and Josene models showed the greatest fit for any empirical sorption process that predicted heterogeneous surface characteristics of DSAC. Factors include beginning pH, catalyst loading, contact time, and temperatures have all been explored in order to determine appropriate adsorption parameters of acid yellow 99 (AY99) from aqueous systems. The isotherm of Langmuir was found to be an excellent match for the experimental data. The pseudo-second-order rate expression was utilized to characterize the dye uptake mechanism. Energy of adsorption activation was also determined to be 14 kJ/mol, suggesting chemisorption as the mode of adsorption. At varying temperatures, thermodynamic limitations such as ΔG^o, ΔH^o, and ΔS^o were established. It was endothermic and unexpected, according to the adsorption thermodynamic characteristics. The findings of the research project are presented in form of chemical activation processes for date seeds produced adsorbents for capturing carbon dioxide and AY99 adsorption.
Application of clay minerals and their derivatives in adsorption from gaseous phase
2021, Applied Clay Science
Reduction of air pollution is one of the major priorities in today's society. The deteriorating over the years air quality has been posing a serious threat of human life. The most problematic gases include nitrogen and sulfur oxides, volatile organic compounds and greenhouse gases, such as carbon dioxide and methane. The interest of the scientific community on developing of new adsorbents with the ability to abate various air pollutants has been incessantly growing. Among many materials used for that purpose, clay minerals have been getting special attention. Clay minerals, due to their unique structure and susceptibility for modifications, are known to have good adsorption properties from aqueous phase, however they can be also applied in air remediation. This review presents examples of clay minerals application in the field of adsorption from gaseous phase; it depicts the use and performance of clay mineral such as kaolinite, halloysite, montmorillonite, bentonite, saponite, vermiculite, illite, sepiolite and palygorskite.

View all citing articles on Scopus

View full text

Surface modification of a low cost bentonite for post-combustion CO2 capture

Highlights

Abstract

Introduction

Section snippets

Materials and PEI-impregnation on bentonite

Characterization

Conclusions

Acknowledgement

International Journal of Greenhouse Gas Control

Microporous and Mesoporous Materials

Microporous and Mesoporous Materials

Fuel

Fuel

Chemical Engineering Journal

Chemical Engineering Journal

Chemical Engineering Journal

Chemical Engineering Science

Chemical Engineering Science

Materials Letters

Microporous and Mesoporous Materials

Applied Surface Science

Applied Clay Science

Journal of Colloid and Interface Science

Environmental Pollution

Chemical Engineering Journal

Microporous and Mesoporous Materials

Applied Clay Science

Surface modification of a low cost bentonite for post-combustion CO₂ capture