TY - JOUR

T1 - Fabrication of a CO2-selective membrane by stepwise liquid-phase deposition of an alkylether functionalized pillared-layered metal-organic framework [Cu2L2P]n on a macroporous support

AU - Bétard, Angélique

AU - Bux, Helge

AU - Henke, Sebastian

AU - Zacher, Denise

AU - Caro, Jürgen

AU - Fischer, Roland A.

PY - 2012/3/1

Y1 - 2012/3/1

N2 - Metal-organic framework (MOF) membranes were prepared by stepwise deposition of reactants. Two pillared layered MOFs with the general formula [Cu2L2P]n (L = dicarboxylate linker, P = pillaring ligand) were selected. Within this family, fine tuning of adsorption affinity and pore size is possible by variation or functionalization of the L and P linkers. Compound 1 was chosen to be non-polar (L = 1,4- naphtalenedicarboxylate = ndc, P = 1,4-diazabicyclo(2.2.2)octane = dabco); in contrast, compound 2 included a polar linker L with two conformationally flexible ether side chains (L = 2,5-bis(2-methoxyethoxy)-1,4-benzene- dicarboxylate = BME-bdc, P = dabco). The polar functionalization is expected to increase the framework affinity for CO2 compared to CH4. The step-by-step, liquid phase deposition of 1 and 2 resulted in pore-plugging of macroporous ceramic supports. The performances of the two MOF membranes were evaluated in gas separation experiments of equimolar CO2/CH 4 mixtures using a modified Wicke-Kallenbach technique. Anti-Knudsen CO2/CH4 separation factors in the range of ∼4-4.5 were obtained for the membrane consisting of the polar 2, whereas the separation of the membrane formed from the non-polar 1 was found to be Knudsen-like.

AB - Metal-organic framework (MOF) membranes were prepared by stepwise deposition of reactants. Two pillared layered MOFs with the general formula [Cu2L2P]n (L = dicarboxylate linker, P = pillaring ligand) were selected. Within this family, fine tuning of adsorption affinity and pore size is possible by variation or functionalization of the L and P linkers. Compound 1 was chosen to be non-polar (L = 1,4- naphtalenedicarboxylate = ndc, P = 1,4-diazabicyclo(2.2.2)octane = dabco); in contrast, compound 2 included a polar linker L with two conformationally flexible ether side chains (L = 2,5-bis(2-methoxyethoxy)-1,4-benzene- dicarboxylate = BME-bdc, P = dabco). The polar functionalization is expected to increase the framework affinity for CO2 compared to CH4. The step-by-step, liquid phase deposition of 1 and 2 resulted in pore-plugging of macroporous ceramic supports. The performances of the two MOF membranes were evaluated in gas separation experiments of equimolar CO2/CH 4 mixtures using a modified Wicke-Kallenbach technique. Anti-Knudsen CO2/CH4 separation factors in the range of ∼4-4.5 were obtained for the membrane consisting of the polar 2, whereas the separation of the membrane formed from the non-polar 1 was found to be Knudsen-like.

KW - CO /CH separation

KW - Membrane

KW - Metal-organic frameworks

KW - Stepwise deposition

UR - http://www.scopus.com/inward/record.url?scp=80054987045&partnerID=8YFLogxK

U2 - 10.1016/j.micromeso.2011.09.006

DO - 10.1016/j.micromeso.2011.09.006

M3 - Article

AN - SCOPUS:80054987045

VL - 150

SP - 76

EP - 82

JO - Microporous and Mesoporous Materials

JF - Microporous and Mesoporous Materials

SN - 1387-1811

IS - 1

ER -