This study is based on the principle that SO
x can be removed by the sulfation of CuO with the catalytic oxidation of SO
2 to SO
3, and NO
x can be removed by the catalytic reduction with NH
3 over CuSO
4 formed. In the previous works, 40mol% CuO-20mol % Al
2O
3-40mol % TiO
2 and 30mol % CuO-20mol % SiO
2-50mol % TiO
2 were found as the preferable catalysts for the simultaneous removal of SO
x and NO
x. In this study, the effects of the addition of Cr
2O
3 etc. to CuO-TiO
2 were examined, and 45-47.5mol % CuO-2. 5-5mol% Cr
2O
3-47.5-52.5mol% TiO
2 catalysts were found. And, the characteristic performances of three kinds of catalysts were compared, and these catalysts proved to be almost the similar catalytic activity and the repeated regenerative stability.
CuO-Cr
2O
3-TiO
2 catalysts of different compositions were prepared by the coprecipitation from CuSO
4, Cr
2 (SO
4)
3 and TiCl
4 aq. solution with NH
4OH aq. solution. The experiments were carried out using a flow-type packed bed reactor for the reduction of NO
x and the simultaneous removal of SO
x and NO
x, and a thermobalance reactor for the basic study on the removal of SO R and the regeneration of catalysts, under atmospheric pressure at 350°C. The inlet gas was 500, 1000ppm (mainly 1000ppm) SO
2-500ppm NO-500ppm NH
3-5% O
2-10% H
2O-N
2. The regeneration of catalysts was carried out by the reduction of CuSO
4 formed to Cu
3N with20% NH
3-7.4% H
2O N
2 at 400°C, and then the oxidation of Cu
3N to CuO with 5 % O
2-10% H
2O-N
2 at 350°C.
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