Catalyst regeneration via chemical treatment and emission tests at idle speeds

Abstract

The present paper examines the possibility of chemical treatment of used catalysts for the purpose of improving catalytic efficiency. The proposed method inserts the catalyst in a bath of a strong organic solvent that dissolves oil, soot and fuel residues, cleaning the active surface of the catalyst. The tests were conducted at low (750 r/min) and high (3100 r/min) idle speeds. The experimental results based on CO, HC and catalyst inlet-outlet temperature difference measurements indicate that after treatment the catalytic efficiency improves considerably (>25 per cent) at low idle (750 r/min). The improvement is even higher at high idle (3100 r/min), exceeding 40 per cent. Therefore, there are strong indications that, if car catalysts underwent a similar treatment at regular service intervals, e.g. every 20 000 km, engine emissions could be considerably reduced and catalyst operational life extended.