PARTIAL REGENERATION OF AN AGED COMMERCIAL AUTOMOTIVE CATALYST

An aged commercial three-way automotive catalyst was examined with res pect to regeneration procedures. Catalyst samples were leached with ac etic acid to remove contaminants accumulated on the catalyst surface d uring operation. The optimum leaching conditions concerning acetic aci d concentration, solution feed rate and temperature were investigated. The leached samples were examined for their catalytic activity (CO an d C2H4 oxidation, NO reduction and N-2 production) in comparison with samples of fresh and aged catalysts. The leaching procedure improves c onsiderably the catalytic activity, where in the case of C2H4 oxidatio n, NO reduction reaches the activity of the fresh catalyst.