MOF semi-finished products
The shaping of MOF-powders to semi-finished MOF parts has a key role for opening up the excellent material properties of MOFs to many applications. By diverse manufacturing methods like extrusion, compression processes, freeze casting, freeze granulation and the novel direct freeze-foaming method, macroscopic MOF parts were produced which are applicable as pellets, honeycomb and foam structures in gas storage systems, as catalyzer substrates or in heat pump applications.
Examples of semi-finished MOF parts: bright material = aluminum fumarate, yellow-brown = Fe-BTC
Depending on the shaping method and MOF material (Fe-BTC, MIL-101 or aluminum fumarate) different pore morphologies and properties are resulting. The achieved porosities of the semi-finished parts (and pellets) vary between 55 and 95 %. At the time being, a possible reduction of the primary specific surface area of the MOFs (700 – 1500 m2) cannot be excluded. Therefore, process parameter, especially concerning the extrusion and freeze-foaming processes, are optimized currently. This enables the transfer of the huge application potential of MOFs to particular shaped bodies with the highest attainable specific surface area.