30results about How to "Good low temperature denitrification activity" patented technology

The invention relates to supported iron-based composite oxide catalyst and a preparation method thereof. The catalyst is made of titanium oxide or aluminum oxide serving as a carrier, iron and cerium serving as a host, and optional one or a plurality of transition metals such as tungsten, molybdenum, titanium and zirconium serving as axillaries. The mole ratio of the iron to the cerium is 1.0-10.0:1. The mole ratio of the host to the auxiliaries is 1.0-5.0:1. The mole ratio of the total of the host and auxiliaries to the carrier is 0.1-0.5:1. The preparation method includes: preparing the auxiliaries and the host into solution, soaking the carrier in the solution, dropwise adding precipitant for precipitation, filtering, drying and calcining. The catalyst has wide denitration temperature window and fine low-temperature denitration activity.

The present invention relates to a rare-earth doped low-temperature denitration catalyst and a preparation method thereof. The main active component of the catalyst is manganese oxide, the carrier is titanium oxide, and cerium oxide and iron oxide are used as cocatalysts. The preparation method includes the following steps: adding solutions of various metal nitrates into a metatitanic acid slurry, then adjusting the pH of the mixture to obtain complete precipitation by using concentrated ammonia, stirring for a while, and performing centrifugal filtration to the resulting suspension, and drying and calcining at a temperature to obtain the rare-earth doped low-temperature denitration catalyst; wherein the molar ratio of each element is as follows: Mn: Fe: Ce: Ti = 5: (0 ~ 2): 4:20. In the temperature range of 140-180 DEG C, the denitration activity of the metal oxide low temperature catalyst of the present invention can reach 80-98%, and the catalyst has a relatively excellent water and sulfur resistance performance.

The invention relates to a denitrification treatment method for flue gas discharged from an ethylene cracking furnace. The flue gas flows sequentially through a radiation section, a convective heat exchange section A, an ammonia injection grid, a convective heat exchange section B, an SCR denitrification reaction section and a convective heat exchange section. C, the preparation method of the catalyst filled in the SCR denitration reaction section is as follows: (1) Add carbon black powder and cerium nitrate to the ethanol solution containing silicon source, mix under ultrasonic dispersion conditions, separate solid-liquid, and carry out solid phase Dry to obtain silicon and cerium modified carbon black powder; (2) Add modified carbon black powder to ethanol solution containing titanium source, add dilute nitric acid solution to form sol-gel, and then treat at high temperature in an oxygen-free atmosphere , roasted in an oxygen-containing atmosphere to obtain a macroporous titania carrier containing silicon and cerium; (3) After mixing the titania carrier, molecular sieve and active component precursor, molding it to obtain a honeycomb denitration catalyst. The method of the invention has good denitrification activity, strong ability to resist water vapor, the catalyst is not easy to crack, and the service life is long.

The invention provides a preparation method of an iron or copper oxide pillared layered manganese oxide low-temperature denitration catalyst. The method mainly uses a shared precursor method. Throughhydroxide preparation, hydroxide oxidization, suction filtration and washing, drying and roasting preparation, the iron or copper oxide pillared layered manganese oxide low-temperature denitration catalyst is obtained. The low-temperature denitration catalyst has the advantages that the active temperature window is low; the denitration efficiency is high; the method is applicable to the SCR (selective catalytic reduction) method low-temperature denitration technology.

The invention discloses a Mn / Co-based low-temperature SOC catalyst and a preparation method thereof. The preparation method comprises the following steps: (1) dissolving manganese-containing metal salt and cobalt-containing metal salt in dimethylformamide, adding an organic ligand and water, and magnetically stirring and uniformly mixing the components to obtain a mixed solution; and (2) carrying out hydrothermal reaction on the obtained mixed solution in a reactor, reacting to obtain Mn / Co double-metal organic framework crystal, soaking the Mn / Co double-metal organic framework crystal in the dimethylformamide and activating the Mn / Co double-metal organic framework crystal, and then purifying, filtering and roasting the activated crystal to obtain the Mn / Co-based low-temperature SCO catalyst. The Mn / Co-based low-temperature SCO catalyst has good low-temperature denitration activity. Compared with an existing low-temperature denitration catalyst, the Mn / Co-based low-temperature SOC catalyst has the advantages that the conversion rate of catalyzed NO is greatly increased, at the low temperature of 150-200 DEG C, the catalyzed conversion rate of NO can reach 50% or above, and existing industrial requirements can be met.