Immobilization of iron porphyrins in tubular kaolinite obtained by an intercalation/delamination procedure

This paper describes the synthesis of a first-generation iron porphyrin catalyst immobilized in a tubular/delaminated kaolinite. Kaolinite was mechanochemically intercalated with urea followed by n-hexylamine, and the catalyst was prepared by submitting the kaolinite/hexylamine intercalation compound to a sonication procedure in the presence of two different iron porphyrin solutions. The materials thus obtained were characterized by UV-vis and IR spectroscopies, XRD, and TEM. The procedure delaminated part of the kaolinite, yielding scroll-like nanotubes, with the metalloporphyrins immobilized in the mixture. The catalytic activity of the materials for cyclohexane and n-heptane oxidation was investigated using iodosylbenzene as the oxygen donor and the products were analyzed by gas chromatography. The results show a promising catalytic system for selective oxidation reactions. (c) 2006 Elsevier Inc. All rights reserved.