email@example.com, firstname.lastname@example.org, email@example.com, firstname.lastname@example.org Reijo Aksela
Kemira Oyj, Luoteisrinne 2, P.O. Box 44, FI-02271 Espoo, Finland
Reijo.email@example.com Juhani Paloniemi
Kemira Oyj, P.O. Box 171, FI-9010 Oulu, Finland
Industrial synthesis of hydrogen peroxide can be achieved by using hydrogenation/oxidation cycle of anthraquinone solution. During hydrogenation step, parallel reactions lead to by-product such as 2-alkyl-5,6,7,8-tetrahydroquinone and 2-alkyl-1,2,3,4,5,6,7,8-octahydroquinone. These species are difficult to oxidize and caused a reduction of global yield of the industrial loop. The working solution should then renew for maintaining hydrogen peroxide production. It’s clearly established that quinone can be recovered by oxidation on alumina catalysis. We propose a study about regeneration of quinone and derivate using microwave energy.
The work is based on a parametric study of a laboratory pilot. This pilot is using microwave in monomode applicator which deliver energy in a continuous tubular reactor. This reactor is part of a loop in which flow the chemical solution. Quinone regeneration occurs on a fixed bed of activated alumina.
Regeneration yield is followed by liquid chromatography of the solution during experiments. Microwave behaviour of the reactor is obtained by incident and reflected power measurements. The main result of this study is to demonstrate microwave efficiency for this heterogeneous reaction. Explanation comes from volumetric heating which induces higher temperature on alumina active sites. But these higher temperatures should be controlled to limit carbonation phenomena on catalysis surface which reduce the efficiency of alumina.