1
|
Lund A, Manohara GV, Song AY, Jablonka KM, Ireland CP, Cheah LA, Smit B, Garcia S, Reimer JA. Characterization of Chemisorbed Species and Active Adsorption Sites in Mg-Al Mixed Metal Oxides for High-Temperature CO 2 Capture. CHEMISTRY OF MATERIALS : A PUBLICATION OF THE AMERICAN CHEMICAL SOCIETY 2022; 34:3893-3901. [PMID: 35573112 PMCID: PMC9097159 DOI: 10.1021/acs.chemmater.1c03101] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 09/07/2021] [Revised: 03/17/2022] [Indexed: 06/15/2023]
Abstract
Mg-Al mixed metal oxides (MMOs), derived from the decomposition of layered double hydroxides (LDHs), have been purposed as adsorbents for CO2 capture of industrial plant emissions. To aid in the design and optimization of these materials for CO2 capture at 200 °C, we have used a combination of solid-state nuclear magnetic resonance (ssNMR) and density functional theory (DFT) to characterize the CO2 gas sorption products and determine the various sorption sites in Mg-Al MMOs. A comparison of the DFT cluster calculations with the observed 13C chemical shifts of the chemisorbed products indicates that mono- and bidentate carbonates are formed at the Mg-O sites with adjacent Al substitution of an Mg atom, while the bicarbonates are formed at Mg-OH sites without adjacent Al substitution. Quantitative 13C NMR shows an increase in the relative amount of strongly basic sites, where the monodentate carbonate product is formed, with increasing Al/Mg molar ratios in the MMOs. This detailed understanding of the various basic Mg-O sites presented in MMOs and the formation of the carbonate, bidentate carbonate, and bicarbonate chemisorbed species yields new insights into the mechanism of CO2 adsorption at 200 °C, which can further aid in the design and capture capacity optimization of the materials.
Collapse
Affiliation(s)
- Alicia Lund
- Materials
Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department
of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - G. V. Manohara
- Research
Center for Carbon Solutions (RCCS), School of Engineering and Physical
Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
| | - Ah-Young Song
- Materials
Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department
of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| | - Kevin Maik Jablonka
- Laboratory
of Molecular Simulation (LSMO), Institut
des Sciences et Ingénierie Chimiques, École Polytechnique
Fédérale de Lausanne (EPFL), Rue de l’Industrie 17, Sion CH-1951, Switzerland
| | - Christopher P. Ireland
- Laboratory
of Molecular Simulation (LSMO), Institut
des Sciences et Ingénierie Chimiques, École Polytechnique
Fédérale de Lausanne (EPFL), Rue de l’Industrie 17, Sion CH-1951, Switzerland
| | - Li Anne Cheah
- Research
Center for Carbon Solutions (RCCS), School of Engineering and Physical
Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
| | - Berend Smit
- Laboratory
of Molecular Simulation (LSMO), Institut
des Sciences et Ingénierie Chimiques, École Polytechnique
Fédérale de Lausanne (EPFL), Rue de l’Industrie 17, Sion CH-1951, Switzerland
| | - Susana Garcia
- Research
Center for Carbon Solutions (RCCS), School of Engineering and Physical
Sciences, Heriot-Watt University, Edinburgh EH14 4AS, U.K.
| | - Jeffrey A. Reimer
- Materials
Science Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
- Department
of Chemical and Biomolecular Engineering, University of California, Berkeley, California 94720, United States
| |
Collapse
|
2
|
Veerabhadrappa MG, Maroto-Valer MM, Chen Y, Garcia S. Layered Double Hydroxides-Based Mixed Metal Oxides: Development of Novel Structured Sorbents for CO 2 Capture Applications. ACS APPLIED MATERIALS & INTERFACES 2021; 13:11805-11813. [PMID: 33657795 DOI: 10.1021/acsami.0c20457] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/12/2023]
Abstract
Layered double hydroxide (LDHs)-based mixed metal oxides (MMOs) are widely studied as the medium to high temperature (200-400 °C) CO2 capture sorbents. However, most of the studies are carried out using the powdered samples. To upgrade these sorbents for industrial-scale CO2 capture, it is important to move away from the powdered form and develop structured sorbents. Moreover, the CO2 capture properties of these sorbents need to be improved in terms of capture capacity and cycling stability. Here we are utilizing a modified amide hydrolysis method to improve the CO2 capture capacities of LDHs-based MMOs. Subsequently, aqueous exfoliation coupled with the freeze-drying technique was utilized to develop LDHs-based novel MMOs. Exfoliated LDH nano sheets were pelletized (2 mm) to circumvent the challenges associated with powder samples when used in industrial-scale applications. The obtained pellets have an average crushing load of 11.1 N and 4.3 MPa of compressive strength, which indicate their good mechanical stability. The MMOs pellets showed a narrow distribution of pores (8-10 nm) with very good surface area (264 m2/g) and pore volume (1.27 cm3/g). They also had much improved CO2 capture capacities at ambient pressure and both low (2.17 mmol/g, 30 °C) and medium temperature (1.43 mmol/g, 200 °C), as compared to previously reported pristine MMOs powder samples. The pelletized structured sorbents also outperformed commercial LDH-based pellets by several fold.
Collapse
Affiliation(s)
- Manohara Gudiyor Veerabhadrappa
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - M Mercedes Maroto-Valer
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Yuhang Chen
- Institute of Mechanical, Process and Energy Engineering, School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - Susana Garcia
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| |
Collapse
|
3
|
Manohara GV, Norris D, Maroto-Valer MM, Garcia S. Acetate intercalated Mg-Al layered double hydroxides (LDHs) through modified amide hydrolysis: a new route to synthesize novel mixed metal oxides (MMOs) for CO 2 capture. Dalton Trans 2021; 50:7474-7483. [PMID: 33970176 DOI: 10.1039/d1dt00602a] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Layered double hydroxide (LDH) based mixed metal oxides (MMOs) are promising high temperature CO2 capture sorbents. In order to improve their CO2 capture capacity, it is crucial to bring in changes to their physicochemical properties such as morphology, particle size, surface area and activity by tuning the synthesis method. Here we report a modified amide hydrolysis method to synthesize LDHs with a mixed morphology and better CO2 capture properties. Acetate intercalated Mg-Al LDHs with two different Mg/Al ratios (3 and 4) were synthesized by employing metal hydroxides as the starting precursors and acetamide as the hydrolysing agent. The resultant LDHs crystallized in a new morphology having a combination of both fibrous and sheet like crystallites. The MMOs derived from Mg-Al-acetate LDHs retained the mixed morphology observed in the precursor LDHs. The resultant MMOs showed almost a threefold increase in the BET surface area, 316 (Mg/Al = 3) and 341 (Mg/Al = 4) m2 g-1, compared to MMOs derived from anion exchanged Mg-Al-acetate LDH (118 m2 g-1). The MMOs synthesized by acetamide hydrolysis captured 1.2 mmol g-1 and 0. 87 mmol g-1 of CO2 at 200 and 300 °C (atmospheric pressure), respectively. The CO2 capture capacity realized was increased more than twofold compared to the CO2 capture capacity of MMOs derived from anion exchanged acetate LDH (0.57 mmol g-1) tested under similar conditions. The developed MMOs showed promising CO2 capture (1.0 mmol g-1) capacity at industrially relevant CO2 concentration (14%).
Collapse
Affiliation(s)
- G V Manohara
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK.
| | - David Norris
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK.
| | - M Mercedes Maroto-Valer
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK.
| | - Susana Garcia
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, UK.
| |
Collapse
|
4
|
Nityashree N, Manohara GV, Maroto-Valer MM, Garcia S. Advanced High-Temperature CO 2 Sorbents with Improved Long-Term Cycling Stability. ACS APPLIED MATERIALS & INTERFACES 2020; 12:33765-33774. [PMID: 32609484 DOI: 10.1021/acsami.0c08652] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/11/2023]
Abstract
Developing novel sorbents with maximum carbonation efficiency and good cycling stability for CO2 capture is a promising route to sequester anthropogenic CO2. In this work, we have employed a green synthesis method to synthesize CaO-based sorbents suitably stabilized by MgO and supported by in situ generated carbon under inert atmosphere. The varied amounts (10-30 wt %) of MgO were used to stabilize the CaO. The supported mixed metal oxide (MMO) sorbents were screened for high-temperature CO2 capture under CO2 rich (86% CO2) and lean (14% CO2) gas streams at 650 °C and atmospheric pressure. The MMO sorbents captured 53-63 wt % of CO2 per gram of sorbent under 86 and 14% CO2, accounting for about 98% carbonation efficiency, which outperforms the CO2 capture capacity of limestone derived CaO (L-CaO) sorbents (22.8 wt %). All of the synthetic MMO sorbents showed greater capture capacity and cyclic stability when compared to benchmark L-CaO. Because of the high carbonation efficiency and cycling stability of g-Ca0.69Mg0.3O sorbent, it was tested for 100 carbonation/regeneration cycles of 5 min each under CO2 lean conditions. The g-Ca0.69Mg0.3O sorbent showed exceptional CO2 capture capacity and cycling stability and retained about 65% of its initial capture capacity after 100 cycles.
Collapse
Affiliation(s)
- N Nityashree
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - G V Manohara
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - M Mercedes Maroto-Valer
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| | - S Garcia
- Research Centre for Carbon Solutions (RCCS), School of Engineering and Physical Sciences, Heriot-Watt University, Edinburgh EH14 4AS, United Kingdom
| |
Collapse
|
5
|
Effects of Immobilized Ionic Liquid on Properties of Biodegradable Polycaprolactone/LDH Nanocomposites Prepared by In Situ Polymerization and Melt-Blending Techniques. NANOMATERIALS 2020; 10:nano10050969. [PMID: 32443604 PMCID: PMC7712423 DOI: 10.3390/nano10050969] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 04/04/2020] [Revised: 04/28/2020] [Accepted: 04/30/2020] [Indexed: 11/17/2022]
Abstract
The high capacity of calcinated layered double hydroxides (LDH) to immobilize various active molecules together with their inherent gas/vapor impermeability make these nanoparticles highly promising to be applied as nanofillers for biodegradable polyester packaging. Herein, trihexyl(tetradecyl)phosphonium decanoate ionic liquid (IL) was immobilized on the surface of calcinated LDH. Thus, the synthesized nanoparticles were used for the preparation of polycaprolactone (PCL)/LDH nanocomposites. Two different methods of nanocomposite preparation were used and compared: microwave-assisted in situ ring opening polymerization (ROP) of ε-caprolactone (εCL) and melt-blending. The in situ ROP of εCL in the presence of LDH nanoparticles with the immobilized IL led to homogenous nanofiller dispersion in the PCL matrix promoting formation of large PCL crystallites, which resulted in the improved mechanical, thermal and gas/water vapor barrier properties of the final nanocomposite. The surface-bonded IL thus acted as nanofiller surfactant, compatibilizer, as well as thermal stabilizer of the PCL/LDH nanocomposites. Contrary to that, the melt-blending caused a partial degradation of the immobilized IL and led to the production of PCL nanocomposites with a heterogenous nanofiller dispersion having inferior mechanical and gas/water vapor barrier properties.
Collapse
|