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Low temperature selective catalytic reduction (SCR) catalyst applications able SCR device configuration directly in the electrostatic precipitator, avoid commercial catalyst V 2 O 5 - (WO 3 ) / TiO 2 flue preheating energy consumption due to the high temperatures necessary for the operation, to reduce the cost of the denitration, but also greatly reduce the poisoning effect of soot, extended catalyst life; but the technology can be match one boiler system with our existing economizer, air preheater and boiler assembly. Therefore, research and development of high-activity, high resistance to the toxicity of the low-temperature SCR catalyst in our country has important economic and practical significance. On the other hand, the combustion flue gas of NO in x 90% 9 5% for NO, NO addition to form a complex, whether in water or lye are not absorption. In order to effectively absorb the of NO x , the portion of the NO in the exhaust gas is oxidized to the of NO 2 , need to find an effective catalyst, dependent in the flue gas itself Oxygen The, NO oxidized to NO the 2 , the oxidation degree of 50% 6 0%, then the wet desulfurization absorbent absorption, wet step simultaneous desulfurization and denitrification . If we can achieve this goal, will be the most competitive of sulfur, nitrogen with off technology. Mesoporous silica-supported iron and manganese oxides the catalyst Mn-Fe/MPS used in catalytic treatment NO x , two angles from catalytic reduction and catalytic oxidation system is developed in this paper. For ammonia selective catalytic reduction of NO x , the optimal catalyst based on the study of a variety of working conditions as well as H 2 O and SO 2 3 temperature selective catalytic reduction of NO x Mn-Fe/MPS catalyst NH . The results show that the catalyst has excellent low temperature SCR activity at 433 K, space velocity was 20,000 h -1 , of the of NO x SCR removal efficiency of up to 99.1%. When the reaction temperature is lower than 413 K, water vapor (10%, the volume fraction φ) to a certain extent to reduce the catalytic activity;, this effect can be completely eliminated when the reaction temperature exceeds 433 K, the of NO x SCR conversion rate reached 97.8%. Low concentrations of SO 2 (100 × 10 -6 , φ) exists under the conditions, 443 K catalytic efficiency can still be stable at 97.2%. , Generated in the case of H 2 O and SO 2 coexistence sulfates and sulfites are deposited on the catalyst surface result in catalyst gradually inactivation; improve the selective catalytic reduction reaction Temperature can delay the deactivation of the catalyst. Also studied the influence of different activation temperature on the recovery of catalyst activity results show that, when the activation temperature reaches 773 K, the activity of the catalyst can be completely restored. The overall performance of the catalyst in the study reported in the literature is superior to other catalysts. NO catalytic oxidation study, the effects of temperature, airspeed, NO inlet concentration and O 2 concentration on the catalytic activity. Results show that NO is oxidized to NO 2 conversion rate having good stability to temperature changes, at 453 K, the inlet NO concentration of 800 × 10 -6 (φ), O 2 concentration of 10% (φ), and the space velocity was 20,000 h -1 , NO oxidation efficiency can be maintained at about 50.6%. When the reaction temperature is higher than 450 K, the water pass into the 10% (φ), the catalyst oxidation activity of unaffected; simultaneously pass into the 10% (φ) of water and 100 × 10 -6 (φ)'s, SO 2 , NO oxidation rate decreased significantly, but still in the 460 K can be maintained at 41%.
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