CO2 Adsorption Enhanced by Tuning the Layer Charge in a Clay Mineral

Author(s):Show less -

Hunvik, Kristoffer W. Bo ^[1] ; Loch, Patrick ^{[2, 3]} ; Wallacher, Dirk ^[4] ; Kirch, Alexsandro ^[5] ; Cavalcanti, Leide P. ^{[6, 7]} ; Riess, Martin ^{[2, 3]} ; Daab, Matthias ^{[2, 3]} ; Josvanger, Vegard ^[1] ; Graetz, Sven ^[8] ; Yokaichiya, Fabiano ^[4] ; Knudsen, Kenneth Dahl ^{[1, 6]} ; Miranda, Caetano Rodrigues ^[5] ; Breu, Josef ^{[2, 3]} ; Fossum, Jon Otto ^[1]

Affiliation

^[1] Norwegian Univ Sci & Technol, Dept Phys, N-7491 Trondheim - Norway

^[2] Univ Bayreuth, Bavarian Polymer Inst, D-95447 Bayreuth - Germany

^[3] Univ Bayreuth, Dept Chem, D-95447 Bayreuth - Germany

^[4] Helmholtz Zentrum Berlin Mat & Energie, D-14109 Berlin - Germany

^[5] Univ Sao Paulo, Inst Fis, Dept Fis Mat & Mecan, BR-05508090 Sao Paulo, SP - Brazil

^[6] Inst Energy Technol IFE, N-2027 Kjeller - Norway

^[7] STFC Rutherford Appleton Lab, LPC ISIS Neutron & Muon Source, Didcot OX11 0QX, Oxon - England

^[8] Ruhr Univ Bochum, Inorgan Chem 1, D-44780 Bochum - Germany

• Document type: Journal article
• Source: Langmuir; v. 37, n. 49, p. 14491-14499, DEC 14 2021.
• Web of Science Citations: 0

Abstract

Due to the compact two-dimensional interlayer pore space and the high density of interlayer molecular adsorption sites, clay minerals are competitive adsorption materials for carbon dioxide capture. We demonstrate that with a decreasing interlayer surface charge in a clay mineral, the adsorption capacity for CO2 increases, while the pressure threshold for adsorption and swelling in response to CO2 decreases. Synthetic nickel-exchanged fluorohectorite was investigated with three different layer charges varying from 0.3 to 0.7 per formula unit of Si4O10F2. We associate the mechanism for the higher CO2 adsorption with more accessible space and adsorption sites for CO2 within the interlayers. The low onset pressure for the lower-charge clay is attributed to weaker cohesion due to the attractive electrostatic forces between the layers. The excess adsorption capacity of the clay is measured to be 8.6, 6.5, and 4.5 wt % for the lowest, intermediate, and highest layer charges, respectively. Upon release of CO2, the highest-layer charge clay retains significantly more CO2. This pressure hysteresis is related to the same cohesion mechanism, where CO2 is first released from the edges of the particles thereby closing exit paths and trapping the molecules in the center of the clay particles. (AU)

• FAPESP's process: 17/02317-2 - Interfaces in materials: electronic, magnetic, structural and transport properties
• Grantee: Adalberto Fazzio
• Support Opportunities: Research Projects - Thematic Grants