High CO2 permeability in supported molten-salt membranes with highly dense and aligned pores produced by directional solidification

Grima, L ; Mutch, GA ; Oliete, PB (Universidad de Zaragoza) ; Bucheli, W ; Merino, RI ; Papaioannou, EI ; Bailey, JJ ; Kok, MD ; Brett, DJL ; Shearing, PR ; Metcalfe, IS ; Sanjuan, ML

Resumen: Composite molten salt-ceramic membranes are promising devices for high-temperature CO2 separation. Intensive material properties impact on separation performance as do membrane geometry (thickness) and microstructure (pore volume fraction, size, connectivity, and tortuosity factor). Although controlling pore size is considered somewhat routine, achieving pore alignment and connectivity is still challenging. Here we report the production of the first gas separation membrane using a porous ceramic matrix obtained from a directionally-solidified magnesium-stabilised zirconia (MgSZ) - MgO fibrilar eutectic as the membrane support. MgO was removed from the parent material by acid-etching to create a porous matrix with highly aligned pores with diameters of similar to 1 mu m. X-ray nano-computed tomography of a central portion (similar to 32, 000 mu m(3)) of the support identified similar to 21% porosity, with all pores aligned within 10 degrees and similar to 76% percolating along the longest sampled length. Employing the matrix as a support for a carbonate molten salt, a high CO2 permeability of 1.41x10(-10) mol m(-1).s(-1).Pa-1 at 815 degrees C was achieved, among the highest reported for supported molten-carbonate membranes (typically 10(-12) to 10(-10) mol m(-1).s(-1).Pa-1 at similar temperatures). We suggest that the high permeability is attributable to the excellent pore characteristics resulting from directional solidification, namely a dense array of parallel, micron-scale pores connecting the feed and permeate sides of the membrane.

Idioma: Inglés

DOI: 10.1016/j.memsci.2021.119057

Año: 2021

Publicado en: JOURNAL OF MEMBRANE SCIENCE 630 (2021), 119057 [15 pp]
ISSN: 0376-7388

Factor impacto JCR: 10.53 (2021)

Categ. JCR: POLYMER SCIENCE rank: 4 / 90 = 0.044 (2021) - Q1 - T1
Categ. JCR: ENGINEERING, CHEMICAL rank: 11 / 143 = 0.077 (2021) - Q1 - T1

Factor impacto CITESCORE: 14.8 - Materials Science (Q1) - Chemical Engineering (Q1) - Biochemistry, Genetics and Molecular Biology (Q1)

Factor impacto SCIMAGO: 1.771 - Biochemistry (Q1) - Physical and Theoretical Chemistry (Q1) - Filtration and Separation (Q1)

Financiación: info:eu-repo/grantAgreement/ES/MINECO-FEDER/MAT2016-77769R

Tipo y forma: Artículo (PostPrint)

Área (Departamento): Área Cienc.Mater. Ingen.Metal. (Dpto. Ciencia Tecnol.Mater.Fl.)