title: Highly selective water adsorption in a lanthanum metal-organic framework.
abstract: We present a new metal-organic framework (MOF) built from lanthanum and pyrazine-2,5-dicarboxylate (pyzdc) ions. This MOF, [La(pyzdc)1.5(H2O)2]⋅2 H2O, is microporous, with 1D channels that easily accommodate water molecules. Its framework is highly robust to dehydration/hydration cycles. Unusually for a MOF, it also features a high hydrothermal stability. This makes it an ideal candidate for air drying as well as for separating water/alcohol mixtures. The ability of the activated MOF to adsorb water selectively was evaluated by means of thermogravimetric analysis, powder and single-crystal X-ray diffraction and adsorption studies, indicating a maximum uptake of 1.2 mmol g(-1) MOF. These results are in agreement with the microporous structure, which permits only water molecules to enter the channels (alcohols, including methanol, are simply too large). Transient breakthrough simulations using water/methanol mixtures confirm that such mixtures can be separated cleanly using this new MOF.
authors.affiliation: Van 't Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam (The Netherlands).
authors.forename: Raoul
authors.initials: R
authors.lastname: Plessius
authors.forename: Rosa
authors.initials: R
authors.lastname: Kromhout
authors.forename: André Luis Dantas
authors.initials: AL
authors.lastname: Ramos
authors.forename: Marilena
authors.initials: M
authors.lastname: Ferbinteanu
authors.forename: Marjo C
authors.initials: MC
authors.lastname: Mittelmeijer-Hazeleger
authors.forename: Rajamani
authors.initials: R
authors.lastname: Krishna
authors.forename: Gadi
authors.initials: G
authors.lastname: Rothenberg
authors.forename: Stefania
authors.initials: S
authors.lastname: Tanase
keywords: adsorption; desiccant; lanthanides; metal-organic frameworks