Study Of La-y-co Composite Oxides For Reduction Of Sulfur Dioxide By Monoxide Carbon To Elemental Sulfur In The Presence Of Oxygen

The SO2 in the flue gas is one of the major air pollutants. How to control the SO2 from the flue gas and change waste into valuables have fatal research significance. Among the various desulfurization technologies, catalytic reduction desulfuration has a huge potential and large developing foreground. However, the O2 existed in the flue gas causes great obstacle to the reductive desulfurization. Therefore the development of reductive desulfurization catalyst has a long life used in a low-temperature and oxygen-containing flue gas system is of great practical significance.Investigated the catalytic performance of La-Y-Co-O catalyst system, for reduction of SO2 by CO to elemental Sulfur, found that La_0.7Y_0.3Co_1.15O₃ catalyst has the best catalytic activity and can be normal use in a low temperature of 325℃, in the reaction space velocity of 6000h-1, 5% O2, 350℃, the SO2 conversion rate is 100%, life up to 80 hours, and its average yield of sulfur up to 96.53%.To find out the causes why La_0.7Y_0.3Co_1.15O₃ catalyst has a good catalytic activity, The structure and surface of the catalysts in the different stages of the experiment were charactered using XRD, SEM. Found that La_0.7Y_0.3Co_1.15O₃ catalyst formed CoS2, La2O2S, La2O3, La2(SO4)3, Y2O3 five substances by XRD. SEM show that the catalyst used 80 hours did not change in the surface appearance, has a good stability. On the base of setting CoS2, La2O2S, Y2O3 as the active sites, carried out the mechanism of reduction of SO2 by CO.