188results about How to "Wide temperature window" patented technology

The invention mainly relates to a SCR (selective catalyctic reduction) flue gas denitration catalyst based on a TiO2-ZrO2 composite metal oxide carrier, belonging to the field of environment protection and environment catalysis. According to the invention, with the nanometer TiO2-ZrO2 as a carrier, WO3 and CeO2 as assistants and V2O5 as an active component, a low-and-medium temperature flue gas denitration catalyst based on the TiO2-ZrO2 composite carrier is obtained. The nanometer TiO2-ZrO2 substitutes the traditional nanometer TiO2 and is used as a carrier, thus the specific area, the heat stability and the acidity of the catalyst are improved; and denitration activity of the catalyst is improved through mutual action among V2O5, WO3 and CeO2; when the ammonia is used as a reducing agent, the catalyst can show very good catalyzing activity at150-450 DEG C.

The invention discloses a method for preparing a Cu-SSZ-13 catalyst through an in-situ synthesis method. A Cu-SSZ-13 molecular sieve sample is prepared by taking acid as an exchange reagent and treating through an in-situ synthesis method. Compared with the currently used ammonium nitrate ion exchange method, the after treatment method for the Cu-SSZ-13 molecular sieve prepared through an in-situ synthesis method is more environment-friendly and effective; the activity of the prepared catalyst is higher; and the hydrothermal stability is better. According to the method, the silica-alumina ratio of the molecular sieve structure is increased while the catalyst having high catalytic activity is obtained; and the obtained Cu-SSZ-13 catalyst has excellent hydrothermal stability, wide temperature window and excellent N2 selectivity, and is very applicable to purification of tail gas from diesel cars.

The invention belongs to the fields of environmental protection and environment catalysis, and specifically relates to a novel mesoporous TiO2 carrier based SCR flue gas denitration catalyst and a preparation method thereof. According to the invention, the mesoporous TiO2 carrier based SCR flue gas denitration catalyst is obtained by using mesoporous TiO2 as a carrier, WO3 and CeO2 as auxiliary agents, and V2O5 as an active component. The compound catalyst comprises, by weight, 83.5-94.5% of TiO2, 0.5-1.5% of V2O5, 4-10% of WO3 and 1-5% of CeO2. The mesoporous TiO2 is employed as the carrier to substitute traditional nano TiO2, so as to substantially increase a specific surface area of the catalyst; and the interactions among V2O5, WO3 and CeO2 increase denitration activity of the catalyst. Besides, the catalyst shows excellent catalytic activity in a temperature range from 200 to 450 DEG C with ammonia as a reduction agent.

The invention relates to a composite smoke SCR (selective catalytic reduction) denitrification catalyst. The composite smoke SCR denitrification catalyst takes honeycomb ceramics, activated carbon or a molecular sieve as a carrier. A composite manganese-molybdenum-nickel-loaded metal oxide is an active component, one or more of copper, chromium, cerium, tin and lanthanum are used as cocatalysts, and the total mass of the active components of the catalyst and the cocatalysts accounts for 15-30% of the mass of the carrier, wherein the molar ratio of Mn to Mo to Ni is 1:(0.1-1):(0.1-1), and the molar ratio of manganese to a metallic element of the co-catalyst is 1: (0.1-1). The catalyst provided by the invention is prepared by adopting a dipping method. Compared with the existing denitrification catalyst suitable for the temperature lower than 300 DEG C, the catalyst provided by the invention has the advantages of high denitrification efficiency, low cost, simple production process, long service life, wide active temperature window, high SO2 and H2O poison resistance capability and the like. Within the temperature from 80 DEG C to 300 DEG C, the conversion rate of NO is more than 90%.

The invention relates to a honeycomb non-vanadium denitration shaping catalyst, a preparation method and application thereof. The shaping catalyst is mainly obtained by shaping catalyst powder and forming additives. The catalyst powder comprises titanium dioxide and additives as main components, wherein the additives are combinations of any four or more than four of copper oxide, zirconium oxide, molybdenum oxide, iron oxide, nickel oxide, cobalt oxide, tungsten oxide and cerium oxide. The forming additives mainly comprise combinations of an enhancer, an inorganic binder, an organic binder, a pore forming agent and a lubricant. The shaping catalyst has excellent anti-SO2 and water vapor poisoning performance, and excellent denitration efficiency and high mechanical strength, and can be used in nitrogen oxide purification of stationary sources (such as a coal-fired power plant and oil catalytic cracking exhaust thereof) and mobile sources (such as diesel exhaust).

The invention relates to an anti-water and anti-sulfur denitration catalyst, a preparation method and application thereof. The catalyst includes titanium dioxide and an additive, both of which are used as the main components, wherein the additive is a combination of any four or more of zirconium oxide, copper oxide, molybdenum oxide, cerium oxide, iron oxide, nickel oxide, cobalt oxide, and tungsten oxide; the surface of the catalyst is coated with a silica coating; the catalyst can be used in the selective catalytic reduction (NH3-SCR) and purification processes of the nitrogen oxides in the flue gas of a stationary source and mobile source. The catalyst adopts non-toxic and harmless raw materials, and has the advantages of being simple and convenient in preparation method, high in catalytic activity, wide in active window, resistant to SO2 poisoning and vapor poisoning for a long time, and environment-friendly.

The invention relates to a cerium-molybdenum-zirconium (Ce-Mo-Zr) composite oxide catalyst. The molar ratio of Zr to Ce in the catalyst is 1:2, and the molar ratio value of Mo to Ce is 0.1-1.5. By the adjustment of the ratio of the three elements, namely cerium, molybdenum and zirconium, the catalyst which is wide in temperature window, high in conversion rate and excellent in temperature resistance and sintering resistance, and is used for converting nitrogen oxides is obtained; the preparation process is simple, the cost is low, and the realization of the industrialization is facilitated.

The invention discloses a CuO loaded CeO2 catalyst for CO preferential oxidation in hydrogen-rich gas and application thereof, especially a ballflower-shaped or petal-shaped CuO loaded CeO2 catalyst. The invention takes copper nitrate as raw material, prepares ballflower-shaped or petal-shaped CuO, and takes it as carrier to synthesize ballflower-shaped or petal-shaped CuO loaded CeO2 catalyst for CO preferential oxidation by isovolumetric dipping method. The preparation process of the catalyst is simple and feasible. The raw material cost is comparatively low. CO preferential oxidation rate and selectivity are high. Temperature window of CO complete conversion is wide.

The invention discloses a rare earth metal modified Cu-SSZ-13 molecular sieve and a preparation method and application thereof. The rare earth metal modified Cu-SSZ-13 comprises a Cu-SSZ-13 molecularsieve which is prepared after ion exchange of a Cu-SSZ-13 molecular sieve prepared by a one-step synthesis method and with a silica-alumina ratio of 3-5, and rare earth metal ions modified at ion exchange sites in a skeleton of the Cu-SSZ-13 molecular sieve. According to the invention, the used raw materials are non-toxic and harmless, the preparation method is simple, and the synthesized catalysthas characteristics of good NH3-SCR catalytic activity, good nitrogen selectivity, good hydrothermal stability and high space velocity resistance, and is suitable for diesel exhaust nitrogen oxide removal and stationary source flue gas denitrification.

The invention belongs to the field of environment friendliness and environment catalysis, in particular relates to an SCR (Selective Catalyctic Reduction) smoke denitration catalyst based on a TiO2-SnO2 composite barrier. The medium-low temperature smoke denitration catalyst based on the TiO2-SnO2 composite barrier is prepared by using nanometer TiO2-SnO2 as a carrier, WO3 and CeO2 as additives and V2O5 as an active component. By adopting the nanometer TiO2-SnO2 for replacing the traditional nanometer TiO2 as the carrier, the specific surface area, the thermal stability and the acidity of the catalyst are increased, the denitration activity of the catalyst is improved through interaction among the V2O5, the WO3 and the CeO2; and when ammonia is used as a reducing agent, better catalytic activity is expressed within a temperature range of 150-450 DEG C.

The invention provides slurry for preparing a denitration integral type catalyst, which comprises a catalyst, silica gel and water. The invention also provides a method for preparing the denitration integral type catalyst by using a dipping method. Compared with the prior art, the slurry of the invention does not include any organic solvent, is simple and environmental-friendly and can reduce theproduction cost. The prepared integral type catalyst has higher denitration activity and wider temperature window, the coating amount of the catalyst can be realized by adjusting the concentration ofthe catalyst in the slurry liquor and the target coating amount can be obtained by only one-time coating so that the preparation process is greatly shortened, the production cost is greatly reduced and large-scale production can be carried out.

The invention discloses a preparation method of an SCR (Selective Catalytic Reduction) vanadium-series catalyst used in denitration of tail gas of a diesel vehicle. Active ingredients are introduced into the catalyst by adopting a simple soaking method, and a catalyst carrier or the catalyst is baked at different temperatures, so that the catalytic performance of the obtained SCR vanadium-series catalyst is improved remarkably, the catalytic activity is greatly increased, and the intensity of the catalyst is greatly increased. The vanadium-series denitration catalyst provided by the inventionhas high denitration efficiency and a wide temperature window, and is suitable for the field of desorption of nitrogen oxides in the tail gas of the diesel vehicle. As proved by the simulated tail gas evaluation of the diesel vehicle in a laboratory, the NOx removing rate of the SCR vanadium-series catalyst prepared with the method is over 90 percent under the condition that the space speed is 30,000 h<-1>, the NO content is 500 ppm and the H2O content is 4 percent at the temperature of 170-469 DEG C.

This invention relates to the cleaning of flue gas released from various combustion processes, particularly a surface deposition NH₃—SCR honeycomb catalyst and its preparation method. The catalyst is composed of framework material, TiO₂, V₂O₅ and WO₃, wherein the framework material is composed of clay, coal ash, mineral waste residue or their mixture. The mass fractions for framework material, TiO₂, V₂O₅, and WO₃ are 60 wt. % to 80 wt. %, 13 wt. % to 33 wt. %, 1 wt. % to 5 wt. %, and 0.1 wt. % to 2 wt. %, respectively. The nano V₂O₅—WO₃—TiO₂ particles were deposited on the surface of particle pore or honeycomb, and the performance of the catalyst could be greatly improved

The invention discloses an in-situ synthesis method and applications of a CuFe-SAPO-34 catalyst, and belongs to the technical field of catalysis. The method comprises the following steps: adding pseudo-boehmite into deionized water, stirring to dissolve pseudo-boehmite, then adding ortho-phosphoric acid and fumed silica, evenly mixing, then adding copper salts and tetraethylene pentamine, fully stirring, then adding Fe salts and n-propylamine; adding fully stirred gel into a hydrothermal reactor to carry out crystallization, after crystallization reactions, cooling to the room temperature, separating solid crystals from the mother liquor, washing the solid crystals by deionized water until the solid crystals become neutral, drying, and finally burning the solid crystals in the air to obtain the CuFe-SAPO-34 microporous molecular sieve catalyst. The CuFe-SAPO-34 catalyst is synthesized in one step; the loading amount of Fe is optimized; and the catalytic performance and low temperature water resisting performance of the CuFe-SAPO-34 catalyst are prominently improved.

The invention discloses a coke oven flue gas denitration catalyst and a preparation method thereof. The preparation method utilizes ammonium metavanadate as an active precursor, chromium nitrate as an auxiliary agent and oxalic acid and hydrochloric acid as reducing agents, and utilizes phosphoric acid to adjust and control the surface acidity of an active component. The preparation method comprises stirring, water bath heating, drying, calcining to obtain a Cr-doped oxyvanadium phosphate active component, adding the Cr-doped oxyvanadium phosphate active component and anatase TiO2 as a carrier with a specific surface area of greater than or equal to 250 m<2>/g into distilled water according to a ratio, carrying out stirring mixing, and carrying out water bath drying and calcining to obtain the catalyst. The catalyst utilizes phosphoric acid to adjust and control the surface acidity of the catalyst, and utilizes aid chromic nitrate to form an intercalation structure and promote formation of adjacent V<5+> and V<4+>. The catalyst has good low temperature denitration activity and strong SO2 and steam poisoning resistance and is suitable for industrial coke oven flue gas denitrification.

The invention discloses a cerium/molecular sieve catalyst used for selective catalytic reduction of nitrogen oxides and a preparation method thereof. The invention overcomes the technical problems of a narrow operating temperature window, poor selectivity at a high temperature and potential harm to the ecological environment and human health of a vanadium-based catalyst system. The catalyst provided by the invention comprises a cerium oxide nanoparticle and a molecular sieve, wherein the molecular formula of the cerium oxide nanoparticle is CeO2, the molecular sieve is MCM56 (n(SiO2)/n(Al2O3)=15-30), and the mass ratio of the cerium oxide nanoparticle to the molecular sieve is 1:19 to 3:1. The invention also provides a preparation method for the catalyst. The preparation method comprises the following steps: synthesizing the cerium oxide nanoparticle by using a hydro-thermal synthesis method; and loading the cerium oxide nanoparticle on the molecular sieve MCM56 for removal of nitrogen oxides through NH3-SCR. The supported catalyst prepared by using the method has the advantages of uniformly dispersed active components, high activity, a wide temperature range and good stability.