CAMIR · Catalytic microreactors for launched systems

Final Activity Report Summary - CAMIR (Catalytic microreactors for launched systems)

Catalysts are all around us in the world. A catalyst is a substance that facilitates a chemical reaction without being used up in the process. Both the chemical industry and the environment depend upon catalysts. Miniaturisation of the catalytic processes is a major challenge in the fields of transportation, household equipment, medical care and energy management. In the present project, a Small-medium enterprise (SME) produced porous disks in the size of a one euro coin and the objective of the present project was to evaluate their use as substrates for supported catalysts. An alumina coating was applied inside the pores via winding, irregular channels, to further enhance the disks' surface. This treatment was performed by means of Forced metal organic chemical vapour infiltration (F-MOCVI) and sol-gel impregnation, with the latter being successful for larger surfaces. In a second step, platinum nanoparticles were deposited on this complex surface structure, by means of F-MOCVD. The selection of proper metalorganic precursors was based on their stability in air, cost and performance. The deposition parameters, such as total pressure and temperature, time and precursor temperature were investigated. The samples were analysed for various characteristics such as overall surface, surface structure, weight, porosity and pore size, through-thickness deposition etc. These characteristics were used in order to approach the optimum operating conditions for processing the catalytic coating. The final samples were used on a catalytic test-bench where the oxidation of carbon monoxide into carbon dioxide, one of the most significant catalytic reactions nowadays, was used in order to determine the efficiency of the produced catalysts. It was shown that a minimum platinum loading was needed in order to achieve any catalytic property and that it was possible to have equally good catalysts in two cases: 1. with small platinum quantities, in case platinum was dispersed in the form of nanoparticles over a large alumina surface; 2. with smaller alumina surfaces and increased platinum particle deposition. The characteristic temperature of 50 % transformation (T50) of carbon monoxide into carbon dioxide was in any case similar to the ones reported in literature, showing that the potential of the catalysts produced in this project was high, even though many improvements could still be undertaken. Special care had to be given to the maximisation of the alumina surface which was deposited inside the pores. The obtained results showed that the catalysts produced as part of this project had similar T50 with industrial catalysts presenting 20 times higher surface area. This led to the assumption that, in case such a surface could be achieved on the present catalysts, its activity would be tenfold.

Data: CORDIS, © European Union