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Mesoporous materials, with a variety of desired properties, are extensively used as absorbents, catalysts, and supports in the chemical and petrochemical industries. Very interesting members of this class of materials are ordered mesoporous carbons (OMC),[1] which are obtained by nanocasting from ordered mesoporous silica [2] as a mould. Porous carbon materials combine chemical inertness, biocompatibility, and thermal stability, and are thus suitable for many different applications. However, carbons are notoriously difficult to separate from solutions, and thus magnetic separation is an attractive alternative to filtration or centrifugation and therefore high on the wish list in catalysis for a long time.[3] Introduction of ferromagnetism in carbon particles while retaining their pore system is difficult, though: The commonly employed strategy to synthesize magnetic carbon materials is the condensation of divalent and trivalent iron salts in an activated carbon slurry in the presence of hydroxide with subsequent calcination.[4] Magnetic silica gel can be synthesized by entrapment of magnetite particles in the forming gel.[5] In the case of carbon, the resulting material has typically surface areas of around 600 m2 gÀ1 and a pore volume below 0.2 cm3 gÀ1.[4] Such synthetic procedures, however, lead to substantial blocking of the pore space, whereas the pore size distribution of the carbons is inherently broad. In addition, the materials are not stable against corrosive media or high temperature, which lead to dissolution of the magnetic component or coalescence of the particles, respectively, thus sacrificing most of the advantages of the carbon. To overcome …