Metal−Organic Frameworks as Adsorbents for Trapping and Preconcentration of Organic Phosphonates

Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, USA.
Analytical Chemistry (Impact Factor: 5.83). 03/2007; 79(4):1290-3. DOI: 10.1021/ac0613075
Source: PubMed

ABSTRACT Metal-organic frameworks (MOFs) have high surface areas and tailorable molecular properties so they have the potential of being selective adsorbents for preconcentrators. In this paper, IRMOF1 is tested as an adsorbent for preconcentration for the first time using dimethyl methylphosphonate (DMMP) as a test case. We find that DMMP is selectively adsorbed on IRMOF1 and is released upon heating to 250 degrees C. Concentration gains of more than 5000 are observed for DMMP with a 4-s sampling time. Sorption capacities are 0.95 g of DMMP/g of IRMOF1. By comparison, dodecane shows a preconcentration gain of approximately 5 under similar conditions. These results demonstrate that MOFs can be quite useful in selective preconcentrators.

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