New Strategy To Enhance CO2 Capture over a Nanoporous

Subscriber access provided by Library, Special Collections and Museums, University of Aberdeen

Communication

A New Strategy to Enhance CO2 Capture over Nanoporous Polyethylenimine Sorbent Xiaoxing Wang, and Chunshan Song Energy Fuels, Just Accepted Manuscript • DOI: 10.1021/ef501997q • Publication Date (Web): 12 Nov 2014 Downloaded from http://pubs.acs.org on November 15, 2014

Just Accepted “Just Accepted” manuscripts have been peer-reviewed and accepted for publication. They are posted online prior to technical editing, formatting for publication and author proofing. The American Chemical Society provides “Just Accepted” as a free service to the research community to expedite the dissemination of scientific material as soon as possible after acceptance. “Just Accepted” manuscripts appear in full in PDF format accompanied by an HTML abstract. “Just Accepted” manuscripts have been fully peer reviewed, but should not be considered the official version of record. They are accessible to all readers and citable by the Digital Object Identifier (DOI®). “Just Accepted” is an optional service offered to authors. Therefore, the “Just Accepted” Web site may not include all articles that will be published in the journal. After a manuscript is technically edited and formatted, it will be removed from the “Just Accepted” Web site and published as an ASAP article. Note that technical editing may introduce minor changes to the manuscript text and/or graphics which could affect content, and all legal disclaimers and ethical guidelines that apply to the journal pertain. ACS cannot be held responsible for errors or consequences arising from the use of information contained in these “Just Accepted” manuscripts.

Energy & Fuels is published by the American Chemical Society. 1155 Sixteenth Street N.W., Washington, DC 20036 Published by American Chemical Society. Copyright © American Chemical Society. However, no copyright claim is made to original U.S. Government works, or works produced by employees of any Commonwealth realm Crown government in the course of their duties.

Page 1 of 17

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

A New Strategy to Enhance CO2 Capture over Nanoporous Polyethylenimine Sorbent Xiaoxing Wang,1* and Chunshan Song, 1,2* 1

Clean Fuels and Catalysis Program, EMS Energy Institute, and Department of Energy &

Mineral Engineering, Pennsylvania State University, 209 Academic Projects Building, University Park, PA 16802, USA 2

Department of Chemical Engineering, Pennsylvania State University, University Park, PA

16802, USA. KEYWORDS: CO2 Capture; Molecular Basket Sorbent; Polyethylenimine; Potassium Carbonate; Flue gas; Sorption.

ABSTRACT: In this communication, a new strategy has been developed to enhance CO2 capture on polyethylenimine-based molecular basket sorbents (MBS) by changing the amine-CO2 reaction chemistry with the addition of potassium carbonate. The gravimetric and volumetric capacity of MBS for CO2 capture from the simulated flue gas at 75 °C and atmospheric pressure was increased greatly by 33% and 74%, respectively. Furthermore, the cyclic stability for regeneration was also improved. This work may provide a new direction for the design and synthesis of solid amine sorbents for CO2 capture.

ACS Paragon Plus Environment

1

Energy & Fuels

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 2 of 17

The rapidly increasing atmospheric CO2 concentration in the past several decades is widely implicated as a major contributor to global climate change.1-4 CO2 emissions from the combustion of fossil fuels and various chemical processes are expected to continue in foreseeable future. To overcome the challenge in mitigating CO2 emissions while meeting the increasing energy demand, CO2 capture, utilization and sequestration (CCUS) has been deemed as an important option. Therefore capture of CO2 in an energy and cost efficient manner from flue gas has attracted great attention worldwide. Liquid amine scrubbing, a traditional and commercially available technology for acidic gases including CO2, is used in large scale in industry because of its large capacity and high selectivity.4,5 However, the regeneration is very energy intensive and costly due to its high heat capacity of aqueous solution.6 Alternatively, adsorption technologies based on solid sorbents are emerging as more promising candidates because the energy penalty for regeneration can be significantly reduced and the corrosion and volatility issues of amine solutions could be minimized in solid sorbents.6,7 Among them, CO2 capture by solid amine sorbents has attracted significant attention and become an increasingly important in research. Various solid amine sorbents have been developed either through surface grafting method impregnation

6,18-47

8-17

or via liquid

and studied, in particular, the polyethylenimine (PEI)-based sorbents. In our

laboratory, we have developed a series of solid amine sorbents so called “molecular basket” sorbents (MBS) in the past decade, which have shown high capacity, high selectivity, good regenerability and stability with lowered material cost for CO2 capture expended for other applications

6,18,49,55,56

18-21,25,48-54

and can be

. The high capacity of PEI-based sorbents can be

ascribed to the increased accessible sorption sites and the significantly enlarged gas-PEI interface area by using a support with large surface area.6 So far, many supports with large pore volume to


2

Page 3 of 17

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

accommodate more PEI and large surface area to increase the dispersion of PEI, including MCM-41

20-24

, MCM-48

40

, SBA-15

6,19,45-47

and KIT-6

27

have been widely studied as one

effective way to achieve higher CO2 capacity. To further improve the sorption capacity, advanced and novel support materials such as silica monolith mesoporous silica foam frameworks (MOFs)

38

30

28

, mesoporous silica capsules

, hierarchical porous silica monolith

32

29

,

and even metal-organic

have developed and explored. However, due to the limitation of PEI

loading amount over support, further improvement of the CO2 capture capacity has become challenging in the development of sorbent materials.

Amine/CO2 molar ratio O + R N-C-O- + H2N R R

R R

2

NH + CO2 R

R

O N-C-O-K+ + KHCO3

1

R Scheme 1. The proposed amine-CO2 reaction chemistry with and without the presence of K2CO3. In this communication, we propose a new strategy to enhance CO2 capture and improve the sorption capacity of PEI-based sorbents by introducing potassium carbonate to change the amine-CO2 reaction chemistry as illustrated in Scheme 1. It is widely accepted that to sorb one mole CO2, two moles of amine sites are normally required to form carbamate species over amine sorbent. While with the presence of K2CO3, we project that only one mole of amine sites is needed to sorb one mole of CO2. As a result, the amine efficiency could be doubled theoretically and CO2 capture capacity can thus be enhanced. In addition, the sorbent density may also be


3

Energy & Fuels

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 4 of 17

increased as well. To the best of our knowledge, this is the first report to introduce the strategy of carbonate-promoted CO2 sorption to the supported amine system. Sorbents developed in this cost-effective method may provide a great potential to capture CO2 more efficiently and may have a major impact on the advancement of current CCUS technologies. Herein, fumed silica (Aerosil®300, Evonik Industry) was used as a support to demonstrate the success of the proposed strategy for CO2 capture enhancement. Polyethylenimine (PEI, Mw 600, Polysciences Inc.) was loaded on the silica support via wet impregnation

19,21

at 40 wt% in the

sorbent, which is termed as MBS. For the K2CO3 promoted sorbent, co-impregnation method was applied with 40 wt% PEI and 6 wt% K2CO3 in the sorbent, named as KC-MBS. CO2 capture was performed at 75 °C in a fixed-bed flow sorption system using a simulated flue gas (15 v% CO2-4.5 v% O2 in N2) or model gas (15 v% CO2 in He) which was introduced at a flow rate of 20 mL/min. Moisture was introduced via bubbling at room temperature. The outlet CO2 concentration was monitored by an on-line GC-TCD. We first evaluated the CO2 capture performance of MBS and KC-MBS sorbents at 75 °C and atmospheric pressure in a fixed-bed flow system using 15 v% CO2 in He as a model gas. The obtained breakthrough curves are presented in Figure 1 and the breakthrough and saturation capacities calculated on the basis of sorbent mass and volume are listed in Table 1. Both sorbents can effectively remove CO2 from the gas stream. The breakthrough capacity and saturation capacity of MBS were 97.6 and 104.7 mg-CO2/g-sorb, respectively. After K2CO3 addition, both the breakthrough capacity and saturation capacity increased by 11%, being 107.9 and 116.0 mg-CO2/g-sorb, respectively for the KC-MBS sorbent. Meanwhile, both sorbents exhibited a sharp breakthrough curve, suggesting a fast CO2 sorption kinetics. The ratio of breakthrough capacity to saturation capacity was ca. 93% for both MBS and KC-MBS, implying


4

Page 5 of 17

that the addition of K2CO3 does not affect the fast kinetics of MBS for CO2 sorption. This value is much higher than that reported in literature, e.g., 57% for HPS-70.32 Even facilitated by surfactant addition, this value is still only 75% for HPS-50-20.32

Outlet CO2 Conc., %

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

15 12 9 MBS KC-MBS

6 3 0 0

5

10 t, min

15

20

Figure 1. Breakthrough curves for CO2 capture from a model gas containing 15 v% CO2 in He over MBS and KC-MBS at 75 °C and atmospheric pressure. Table 1. The calculated breakthrough and saturation capacities.

Packing density Sample

Gravimetric capacity

Volumetric capacity

(mg-CO2/g-sorb)

(mg-CO2/ml-sorb)

BT

Sat.

BT

Sat.

(g/ml)

MBS

0.45

97.6

104.7

43.7

46.9

KC-MBS

0.59

107.9

116.0

63.3

68.0

Increase, %

31

11

11

45

45

BT = breakthrough; Sat. = Saturation. Conditions: gas, 15 v% CO2-He; flow rate, 20 ml/min; T, 75 °C; P, 1 atm.


5

Energy & Fuels

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 6 of 17

The MBS and KC-MBS sorbents were analyzed via N2 physisorption on a Micromeritics ASAP 2020 for their pore properties. MBS exhibited a surface area of 38 m2/g, pore volume of 0.44 cm3/g and a pore diameter of 33.2 nm. With the addition of K2CO3, both the surface area and the pore volume decreased to 16 m2/g, and 0.22 cm3/g, respectively. While the pore size changed little, being 32.1 nm. The results indicate that the change of the pore properties induced by the addition of K2CO3 is not responsible for the increase in the CO2 capture capacity with the addition of K2CO3. To confirm the change in the amine-CO2 reaction chemistry upon the addition of potassium carbonate, the prepared MBS and KC-MBS were exposed to air a certain time and then characterized by the diffuse-reflectance infrared Fourier transform spectroscopy (DRIFTS) over a Nicolet NEXUS 470 FTIR spectrometer (Thermo Electron Corp.), which were collected at room temperature and atmospheric pressure with KBr as the background and an IR resolution of 4 cm-1. The major difference was the IR band at 1650 cm-1 observed over MBS which is attributed to the N-H deformation in RNH3+ due to CO2 sorption,7 was greatly reduced over the KC-MBS sample (see Figure S1 in the Supporting Information). It indicates that the formation of carbamate species on MBS is reduced in the presence of K2CO3, which confirms the role of K2CO3 described in Scheme 1. To further verify our assumption on the promotion effect of K2CO3 addition, we have examined the effect of moisture on CO2 capture over the two sorbents. With the presence of moisture, the CO2 sorption capacity of MBS is forecasted to be larger because the reaction shifts gradually from carbamate formation to bicarbonates

48,57

, as demonstrated by the following

equation. R2NH + CO2 + H2O → (R2NH2)+ + HCO3-


6

Page 7 of 17

However, for MBS with K2CO3 addition, as illustrated in Scheme 1, it is projected that negligible increase would be obtained, especially at low H2O content, as bicarbonate species have already formed with K2CO3.

Outlet CO2 Conc.,%

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

15 10

MBS-dry MBS-wet KC-MBS-dry KC-MBS-wet

5 0 0

10

20 30 t, min

40

Figure 2. Breakthrough curves for CO2 capture from a simulated flue gas containing 15 v% CO2-4.5 v% O2-80.5 v% N2 over MBS and KC-MBS at 75 °C and atmospheric pressure with and without the presence of moisture (3 v% H2O by bubbling). Here, a simulated flue gas containing 15 v% CO2, 4.5 v% O2 and 80.5 v% N2 was used instead of the model gas so that the data would be more applicable to real applications. The moisture was introduced by bubbling water at room temperature, corresponding to a water vapor content of about 3 v%. The breakthrough curves under dry and wet conditions are shown in Figure 2. As it can be seen, the developed sorbents worked well for the simulated flue gas under the conditions studied and CO2 was 100% captured before breakthrough. On the basis of breakthrough curves, the saturation capacities and the corresponding amine efficiency, which is defined as the molar ratio of sorbed CO2 to the amine groups (NH-) in the sorbent, were obtained and are presented in


7

Energy & Fuels

Figure 3. For comparison, the capacities and amine efficiency from the model gas are also presented. As anticipated, with the presence of 3 v% moisture, the sorption capacity of MBS increased about 14% from 90.9 to 104.0 mg-CO2/g-sorb. While little change in the CO2 capacity was observed on KC-MBS. This result proves our assumption and projection about the

Gravimetric Capacity (mg/g)

120 120

Volumetric Capacity (mg/ml) model gas–dry 32 simulated flue gas–dry simulated flue gas–wet

100 100

30

8080

28

6060

26

4040

24

2020

22

00

Amine efficiency, %

promotion effect of K2CO3 on CO2 capture of MBS shown in Scheme 1.

CO2 Capacity CO2 Capacity, mg/g or mg/ml

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 8 of 17

20 MBS

KC-MBS

MBS

KC-MBS

Figure 3. Comparison of the CO2 capacity and amine efficiency of MBS and KC-MBS for CO2 capture from different gas streams measured in a fixed-bed flow system at 75 °C and atmospheric pressure. Compared to MBS, KC-MBS showed much higher CO2 capacity under both conditions. Under dry conditions, the capacity of MBS increased significantly by 33% after K2CO3 addition, reaching 120.9 mg-CO2/g-sorb. The percentage increase is more than double of that from the promotion of 3 v% moisture (14%), suggesting K2CO3 is more effective than 3 v% moisture to


8

Page 9 of 17

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

enhance CO2 capture of MBS. The amine efficiency also improved much from 22% to 30%. Under wet conditions, an increase of 16% in the CO2 capacity was also obtained over MBS with the addition of K2CO3. The results clearly show the considerable enhancement on CO2 capture of MBS with the addition of K2CO3. Not only the gravimetric capacity increased, but also the volumetric capacity improved even more significantly (Figure 3, right side). Under dry conditions, it was 45.4 mg-CO2/ml-sorb for MBS. After K2CO3 addition, this capacity increased dramatically by 74%, to 79.2 mg-CO2/mlsorb. Even under wet conditions, an increase as high as 52% was still obtained. In practical applications, the volumetric capacity is a very important parameter. The higher the volumetric capacity, the more compact size the sorber, which further means easier handling and less investment cost for the equipment. Therefore, the high volume-based sorption capacity is another significant advantage induced by the addition of K2CO3. Interestingly, over MBS, the CO2 sorption capacity (90.9 mg-CO2/g-sorb) for the simulated flue gas was lower than that for the model gas (104.7 mg-CO2/g-sorb) (Figure 3,left side), implying that the existence of O2 and N2 affects the CO2 sorption performance of MBS. However, over KC-MBS sorbent, such an influence was not observed. The CO2 sorption capacity was almost the same as the value is within the error range (±5%). It reflects that CO2 sorption on MBS has been greatly enhanced by the addition of K2CO3 and the sorbent becomes more selective to CO2 and more resistant to the effect of O2 and N2. The effect of K2CO3 addition on the relative selectivity of CO2 to O2 and N2 over MBS will be further studied and clarified. The long-term stability of a robust sorbent is critical in reducing the cost for practical CO2 capture applications. Thus, the cyclic stability of MBS before and after K2CO3 addition was


9

Energy & Fuels

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 10 of 17

assessed in the fixed-bed flow system for 50 cycles, which is presented in Figure 4. In each cycle, more than 99% of sorbed CO2 was desorbed over both sorbents under the desorption conditions studied. After 50 cycles, the CO2 capacity of MBS dropped to 86.2 mg-CO2/g-sorb, about 81% of its initial capacity. The loss of capacity can be ascribed to the volatilization of PEI polymer 30 and/or the formation of urea 58 under current conditions. After K2CO3 addition, higher CO2 capacity was obtained during all the 50 cycles. In addition, the KC-MBS showed a better reversible CO2 capture performance. After 50 cycles, the capacity as high as 104.5 mg-CO2/gsorb was still obtained over KC-MBS sorbent, which was 90% of the initial capacity, even at such a progressive temperature of 120 °C for desorption. On the contrary, the good CO2 regeneration performance of solid amine sorbents reported in literature was mostly conducted at much lower temperatures because of the concerns of the amine thermal stability at higher temperatures, for example, 75 °C for the surfactant promoted PEI-HPS sorbents

32

and 100 °C

for the silica foam supported PEI sorbents 30. Sayari and Belmabkhout studied the cyclic stability of amine-grafted pore-extended MCM-41 sorbents at the desorption temperature of 120 °C.58 They found that the percentage for the loss of sorption capacity was 14% for TRI-50/120-d after 40 cycles and as high as 45% for MONO-105/105-d and TRI-105/105-d.58 In comparison, the sorbents developed in this work exhibited superior cyclic stability for CO2 capture. The enhanced cyclic stability of KC-MBS may be attributed to the interaction between K2CO3 and amine groups, which is under investigation and will be reported in the future.


10

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

CO2 Uptake, mg/g

Page 11 of 17

140 120 100 80 60 40 20 0

MBS

2

16

KC-MBS

26 36 Cycle Number

46

Figure 4. Cyclic stability of MBS and KC-MBS sorbent for 50 sorption-desorption cycles. The CO2 sorption was performed at 75 °C and atmospheric pressure under 15 v%-He gas stream for 20 min, followed by the desorption at 120 °C and atmospheric pressure under pure He for 20 min. In summary, we report a new strategy to enhance the CO2 capture of molecular basket sorbent on the basis of altering the amine-CO2 reaction chemistry. By adding potassium carbonate, the stoichiometric value for amine-CO2 reaction may be changed from 2 to 1, thus improving the amine efficiency and CO2 capture capacity. With the addition of K2CO3, the gravimetric and volumetric capacities of MBS for CO2 capture from the simulated flue gas were increased greatly by 33%, and 74%, respectively. Furthermore, the cyclic stability of MBS sorbent for regeneration was also improved by the addition of K2CO3, which may be attributed to the changed amine-CO2 reaction chemistry by K2CO3 and the interaction between PEI and incorporated K2CO3. This work suggests a new direction for the design and synthesis of future solid amine sorbents with easy preparation, potential cost effectiveness and energy efficiency for CO2 capture.


11

Energy & Fuels

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 12 of 17

ASSOCIATED CONTENT Supporting Information. DRIFT spectra of MBS, KC-MBS and K2CO3 after air-exposure for a certain time with KBr as the background and an IR resolution of 4 cm-1. This material is available free of charge via the Internet at http://pubs.acs.org. AUTHOR INFORMATION Corresponding Author *E-mail: [email protected] (C.S.), Tel: (814) 863-4466, Fax: (814) 865-3573; [email protected] (X.W.) ACKNOWLEDGMENT The authors gratefully acknowledge the partial financial support from the Pennsylvania State University through the Penn State Institutes of Energy and the Environment, and the U.S. Department of Energy through the National Energy Technology Laboratory for the work on CO2 capture. REFERENCES (1)

Keith, D. W. Science 2009, 325, 1654.

(2) Song, C. S. Catal. Today 2006, 115, 2. (3) Cox, P. M.; Betts, R. A.; Jones, C. D.; Spall, S. A.; Totterdell, I. J. Nature 2000, 408, 184. (4) Haszeldine, R. S. Science 2009, 325, 1647. (5)

Rochelle, G. T. Science 2009, 325, 1652.


12

Page 13 of 17

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

(6)

Ma, X. L.; Wang, X. X.; Song, C. S. J. Am. Chem. Soc. 2009, 131, 5777.

(7)

Wang, X. X.; Schwartz, V.; Clark, J. C.; Ma, X. L.; Overbury, S. H.; Xu, X. C.; Song, C.

S. J. Phys. Chem. C 2009, 113, 7260. (8)

Choi, S.; Gray, M. L.; Jones, C. W. ChemSusChem 2011, 4, 628.

(9)

Choi, S.; Drese, J. H.; Jones, C. W. ChemSusChem 2009, 2, 796.

(10) Hicks, J. C.; Drese, J. H.; Fauth, D. J.; Gray, M. L.; Qi, G. G.; Jones, C. W. J. Am. Chem. Soc. 2008, 130, 2902. (11) Huang, H. Y.; Yang, R. T.; Chinn, D.; Munson, C. L. Ind. Eng. Chem. Res. 2003, 42, 2427. (12) Knowles, G. P.; Delaney, S. W.; Chaffee, A. L. Ind. Eng. Chem. Res. 2006, 45, 2626. (13) Liu, X. W.; Zhou, L.; Fu, X.; Sun, Y.; Su, W.; Zhou, Y. P. Chem. Eng. Sci. 2007, 62, 1101. (14) Hiyoshi, N.; Yogo, K.; Yashima, T. Micropor. Mesopor. Mater. 2005, 84, 357. (15) Harlick, P. J. E.; Sayari, A. Ind. Eng. Chem. Res. 2007, 46, 446. (16) Serna-Guerrero, R.; Belmabkhout, Y.; Sayari, A. Adsorption-J. Inter. Ads. Soc. 2010, 16, 567. (17) Kassab, H.; Maksoud, M.; Aguado, S.; Pera-Titus, M.; Albela, B.; Bonneviot, L. RSC Adv. 2012, 2, 2508.


13

Energy & Fuels

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 14 of 17

(18) Wang, X. X.; Ma, X. L.; Zhao, S. Q.; Wang, B.; Song, C. S. Energy Environ. Sci. 2009, 2, 878. (19) Wang, X. X.; Ma, X. L.; Song, C. S.; Locke, D. R.; Siefert, S.; Winans, R. E.; Mollmer, J.; Lange, M.; Moller, A.; Glaser, R. Micropor. Mesopor. Mater. 2013, 169, 103. (20) Xu, X. C.; Song, C. S.; Andresen, J. M.; Miller, B. G.; Scaroni, A. W. Energy Fuels 2002, 16, 1463. (21) Xu, X. C.; Song, C. S.; Andresen, J. M.; Miller, B. G.; Scaroni, A. W. Micropor. Mesopor. Mater. 2003, 62, 29. (22) Belmabkhout, Y.; Serna-Guerrero, R.; Sayari, A. Chem. Eng. Sci. 2010, 65, 3695. (23) Heydari-Gorji, A.; Belmabkhout, Y.; Sayari, A. Langmuir 2011, 27, 12411. (24) Heydari-Gorji, A.; Yang, Y.; Sayari, A. Energy Fuels 2011, 25, 4206. (25) Wang, X. X.; Ma, X. L.; Schwartz, V.; Clark, J. C.; Overbury, S. H.; Zhao, S. Q.; Xu, X. C.; Song, C. S. Phys. Chem. Chem. Phys. 2012, 14, 1485. (26) Wang, X. X.; Song, C. S. Catal. Today 2012, 194, 44. (27) Chen, C.; Son, W. J.; You, K. S.; Ahn, J. W.; Ahn, W. S. Chem. Eng. J. 2010, 161, 46. (28) Chen, C.; Yang, S. T.; Ahn, W. S.; Ryoo, R. Chem. Commun. 2009, 3627. (29) Qi, G. G.; Wang, Y. B.; Estevez, L.; Duan, X. N.; Anako, N.; Park, A. H. A.; Li, W.; Jones, C. W.; Giannelis, E. P. Energy Environ. Sci. 2011, 4, 444. (30) Qi, G. G.; Fu, L. L.; Choi, B. H.; Giannelis, E. P. Energy Environ. Sci. 2012, 5, 7368.


14

Page 15 of 17

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

(31) Goeppert, A.; Meth, S.; Prakash, G. K. S.; Olah, G. A. Energy Environ. Sci. 2010, 3, 1949. (32) Wang, J. T.; Long, D. H.; Zhou, H. H.; Chen, Q. J.; Liu, X. J.; Ling, L. C. Energy Environ. Sci. 2012, 5, 5742. (33) Wang, K.; Shang, H. Y.; Li, L.; Yan, X. L.; Yan, Z. F.; Liu, C. G.; Zha, Q. F. J. Nat. Gas Chem. 2012, 21, 319. (34) He, H. K.; Li, W. W.; Zhong, M. J.; Konkolewicz, D.; Wu, D. C.; Yaccato, K.; Rappold, T.; Sugar, G.; David, N. E.; Matyjaszewski, K. Energy Environ. Sci. 2013, 6, 488. (35) Estevez, L.; Dua, R.; Bhandari, N.; Ramanujapuram, A.; Wang, P.; Giannelis, E. P. Energy Environ. Sci. 2013, 6, 1785. (36) Wang, J. T.; Wang, M.; Zhao, B. B.; Qiao, W. M.; Long, D. H.; Ling, L. C. Ind. Eng. Chem. Res. 2013, 52, 5437. (37) Meth, S.; Goeppert, A.; Prakash, G. K. S.; Olah, G. A. Energy Fuels 2012, 26, 3082. (38) Lin, Y. C.; Yan, Q. J.; Kong, C. L.; Chen, L. Scientific Reports 2013, 3, 1. (39) Li, P. Y.; Ge, B. Q.; Zhang, S. J.; Chen, S. X.; Zhang, Q. K.; Zhao, Y. N. Langmuir 2008, 24, 6567. (40) Son, W. J.; Choi, J. S.; Ahn, W. S. Micropor. Mesopor. Mater. 2008, 113, 31. (41) Liu, Y. M.; Ye, Q.; Shen, M.; Shi, J. J.; Chen, J.; Pan, H.; Shi, Y. Environ. Sci. Technol. 2011, 45, 5710.


15

Energy & Fuels

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Page 16 of 17

(42) Zheng, F.; Tran, D. N.; Busche, B. J.; Fryxell, G. E.; Addleman, R. S.; Zemanian, T. S.; Aardahl, C. L. Ind. Eng. Chem. Res. 2005, 44, 3099. (43) Franchi, R. S.; Harlick, P. J. E.; Sayari, A. Ind. Eng. Chem. Res. 2005, 44, 8007. (44) Fauth, D. J.; Gray, M. L.; Pennline, H. W.; Krutka, H. M.; Sjostrom, S.; Ault, A. M. Energy Fuels 2012, 26, 2483. (45) Yue, M. B.; Chun, Y.; Cao, Y.; Dong, X.; Zhu, J. H. Adv. Funct. Mater. 2006, 16, 1717. (46) Yan, X. L.; Zhang, L.; Zhang, Y.; Yang, G. D.; Yan, Z. F. Ind. Eng. Chem. Res. 2011, 50, 3220. (47) Sanz, R.; Calleja, G.; Arencibia, A.; Sanz-Perez, E. S. Appl. Surf. Sci. 2010, 256, 5323. (48) Xu, X. C.; Song, C. S.; Miller, B. G.; Scaroni, A. W. Ind. Eng. Chem. Res. 2005, 44, 8113. (49) Xu, X. C.; Song, C. S.; Miller, B. G.; Scaroni, A. W. Fuel Process. Technol. 2005, 86, 1457. (50) Wang, D. X.; Ma, X. L.; Sentorun-Shalaby, C.; Song, C. S. Ind. Eng. Chem. Res. 2012, 51, 3048. (51) Zhang, Z. H.; Ma, X. L.; Wang, D. X.; Song, C. S.; Wang, Y. G. AIChE J. 2012, 58, 2495. (52) Wang, D. X.; Sentorun-Shalaby, C.; Ma, X. L.; Song, C. S. Energy Fuels 2011, 25, 456.


16

Page 17 of 17

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60

Energy & Fuels

(53) Wang, W. L.; Wang, X. X.; Song, C. S.; Wei, X. L.; Ding, J.; Xiao, J. Energy Fuels 2013, 27, 1538. (54) Wang, W. L.; Xiao, J.; Wei, X. L.; Ding, J.; Wang, X. X.; Song, C. S. Appl. Energy 2014, 113, 334. (55) Wang, X. X.; Ma, X. L.; Sun, L.; Song, C. S. Green Chem. 2007, 9, 695. (56) Wang, X. X.; Ma, X. L.; Xu, X. C.; Sun, L.; Song, C. S. Top. Catal. 2008, 49, 108. (57) Serna-Guerrero, R.; Da'na, E.; Sayari, A. Ind. Eng. Chem. Res. 2008, 47, 9406. (58) Sayari, A.; Belmabkhout, Y. J. Am. Chem. Soc. 2010, 132, 6312.


17

New Strategy To Enhance CO2 Capture over a Nanoporous

Recommend Documents