Abstract:
Combined with the superior resistance to sulfur as well to water of antimony, and the ability of tungsten to increase the activity of vanadium-based catalysts, antimony and tungsten were used as promoters to prepare the V-W-Sb/Ti catalysts using impregnation method, and the denitrification of the modified catalysts made by different preparation conditions was investigated. The tests of the activity and the resistance to H
2O and SO
2 were carried out in a fixed bed reactor, and the catalysts were characterized by N
2 physical adsorption-desorption, X-ray diffraction, NH
3-TPD test and H
2-TPR. In the case of the selected catalyst formulation 3V
2O
5-5WO
3-2Sb
2O
3/90TiO
2, the experimental results show that the catalyst prepared by using antimony acetate as the precursor has better activity than that prepared by using antimony chloride as precursor; the catalyst prepared by calcination at 400℃ has higher denitrification efficiency than that prepared at 500℃; the difference in the number of impregnation steps has a limited effect on the activity of the catalyst. At the denitrification temperature of 180℃, and 10% (volume ratio) H
2O and 0.01%SO
2 added in the feed gas, under the same calcination temperature, the activity of the catalyst prepared by two-step impregnation and using antimony acetate as the precursor is only 2% higher than the catalyst prepared by one-step impregnation and using antimony chloride as the precursor, the latter one has a simple and convenient preparation process, so it has more industrial application value.