OP-II-3

PP-III-50NEW CONCEPT FOR A SELF CLEANING HOUSEHOLD OVENPietro Palmisano, Hernandez S. P., Debora Fino, Nunzio RussoDepartment of Materials Science and Chemical Engineering, Politecnico di TorinoCorso Duca degli Abruzzi 24, 10129 Torino, pietro.palmisano@polito.itThe household appliances industry has recently developed various solutions ofself-cleaning oven [1,2] by means of a pyrolitic step at 550°C for 1h to reduce theresidual soil, after a normal cooking cycle. The aim of this paper is to implement theconcept of a self-cleaning household oven working at 400°C for 1h, by means of thecatalytic activity of CeO 2 deposited over the oven walls as reported in our previouspaper [3].The first part of this work has been focused to assess the capability of the CeO 2to promote the oxidation of selected cooking soils (milk in powder, tomato sauce,apricot jam, bouillon cube of fried ingrediants) by means of a TPC pilot described in[3]. The second step has been focused to compare various catalyst depositionmethods over pieces (5X5cm) of oven walls based on a standard ceramic enamel.The gel-combustion, the sol-gel, the wet-urea and the powder coating depositionmethods have been adopted. The obtained catalityc layers have been evaluated interms of adhesion, penetration and exposed surface respect to the standard enamellayer used as support, using an SEM-EDS technique (Figure 1).Samples prepared by means of the above mentioned deposition methods havebeen tested towards the abatement of cooking soils (listed above, plus olive oil) bymeans of gravimetric experiments carried out at 300°C and 400°C (for 1 hour) bymeasuring the weight before and after the thermal treatment which simulate acooking cycle. The obtained results have been compared with those obtained by apyrolitic enamel sample but at 550°C for 1 hour. Table I reports, for the sake ofbriefness, the percentages of residual olive oil resulting after the thermal treatment.The SEM micrographs reported in Figure1 show that the best CeO 2 layer has beenobtained by means of the wet-urea deposition method. The gravimetric testsconfirmed this consideration. The residual olive oil value, after 1h at 400°C, iscomparable to the value measured at 550°C with the pyrolitic layer (1% and 0.5%,respectevely). It is worthwhile to notice that this new concept allows high energysaving and low insulating material costs.531