382results about How to "Good activity at low temperature" patented technology

A catalyst for an integrated supported carbon modular sieve comprises an integrated beehive cordierite, a carbon-nano tube and an HZSM-5 modular sieve, wherein the carbon-nano tube takes 7-20 proportions, HZSM-5 takes 10-30 proportions, and cordierite tales 60-80 proportions. The preparation method is that: carbon-nano tube is produced in situ on the integrated beehive cordierite by using chemical vapor deposition firstly, and the carbon-nano tube is taken as carrier, then the ZSM-5 modular sieve is developed on the carrier by using a secondary growth method. The catalyst for an integrated supported carbon-modular sieve can be used for the gas-phase synthesis of dimethyl ether DME by the dehydration of methanol.

The invention relates to a method for preparing a low-temperature SCR (selective catalytic reduction) denitration catalyst, and belongs to the technical field of catalysis. The denitration catalyst has a good nitric oxide removal rate, water resistance and sulfur resistance when the temperature of flue gas ranges from 150 DEG C to 250 DEG C. The method includes dissolving ammonium metavanadate, transition metal salts and titanium and tungsten powder in water; and drying and calcining the mixed liquor to prepare the low-temperature SCR denitration catalyst. The prepared catalyst is good in low-temperature activity, and can keep the good nitric oxide removal rate, the water resistance and the sulfur resistance at the temperature ranging from 150 DEG C to 250 DEG C. In addition, owing to the high activity and poison resistance at the temperature ranging from 150 DEG C to 250 DEG C, the catalyst can be applied to the field of flue gas after the flue gas flows via dust catchers of thermal power plants and flue gas, with the temperature ranging from 150 DEG C to 250 DEG C, of industrial furnaces and the like, and denitration catalyst technology and application breakthrough is realized.

The invention relates to a flue gas denitration integral type catalyst using an aluminum-based ceramic as a carrier and a preparation method thereof. The invention uses the aluminum-based ceramic as a first carrier, an alumina is used as a second carrier, and CeO2 which is added with proper amounts of doped metal oxides is used as an active constituent. The first carrier is used as a benchmark, the content mass percentage of the alumina is 3 to 40wt percent and the load content mass percentage of the CeO2 and the doped metal oxides which is used as the active constituent is 1 to 26wt percent. The adopted preparation method is to impregnate the Ce salt and the doped metal salt composite solution to prepare an active catalytic component coating after impregnating the aluminum-based ceramic with an alumina sol and being roasted driedly to prepare an alumina coating. Compared with the prior art, the flue gas denitration integral type catalyst and the preparation method thereof not only improve the mechanicalness and the heat stability of the catalyst carrier and reduce the loading amount of the active constituent, but also are environmental protection without a secondary pollution, improve the activity of the catalyst and expand a window of activity temperature in a low temperature.

The invention relates to a method for selective hydrogenation of full-run pyrolysis gasoline, which mainly solves the technical problem in the prior art that it is difficult to selectively hydrogenate full-run pyrolysis gasoline with high colloid and free water content. The present invention adopts the pyrolysis gasoline and hydrogen of the hydrocarbon compound fraction with C5 hydrocarbon to dry point of 204 DEG C as raw materials, the reaction temperature is 30 to 80 DEG C, the reaction pressure is 2.0 to 3.0 MPa, and the fresh oil space velocity is 2.5 to 5.0 hour-1, under the condition that the hydrogen/oil volume ratio is 60-120:1, the raw material is contacted with the catalyst and reacts to convert the diolefin and alkenyl aromatic components in the raw material into monoolefin and alkylaromatic. Including alumina support, active component metal palladium or its oxide, at least one element selected from IA or IIA in the periodic table or its oxide, at least one element selected from IVA or VA in the periodic table or its oxide Oxide, the specific surface area of ​​the carrier is 40-160 m2/g, the total pore volume is 0.3-1.2 ml/g, and the carrier has a technical solution of composite pore distribution, which solves this problem well and can be used for full-run pyrolysis gasoline In the industrial production of selective hydrogenation.

The present invention relates to a nickel catalyst for selective hydrogenation. The catalyst composition includes the following components: (by wt%) (a), 5.0-40.0% of metal nickel or its oxide; (b), 0.01-20.0% of at least one element selected from molybdenum or tungsten or its oxide; (c), 0.01-10.0% of at least one element selected from rare earth elements or its oxide; (d), 0.01-2.0% of at least one element selected from IA or IIA of periodic table of chemical elements or its oxide; (e), 0-15.0% of at least one element selected from Si, P, B or F or its oxide; (f), 0-10.0% of at least one element selected from IVB of periodic table of chemical elements or its oxide; and (g), the rest is aluminium oxide. Said catalyst can be used for pyrolysis gasoline hydrotreating production.

The present invention discloses a manganese-sodium-tungsten-silicon composite oxide oxidative coupling of methane catalyst containing or not containing titanium, obtained by loading manganese-sodium-tungsten onto a titanium-silicon molecular sieve or a pure silicon molecular sieve by means of a step-by-step impregnation method and calcination. The manganese-sodium-tungsten-silicon composite oxide catalyst containing or not containing titanium has the following structural formula: vMnO2·xNa2O·yWO3·zTiO2·(100-v-x-y-z)SiO2, the v, x, y, and z respectively representing the fractional quality occupied by metal manganese oxide, sodium oxide, tungsten oxide and titanium oxide, 0.3≤v≤16, 0.1≤x≤5, 0.6≤y≤21, 0.0≤z≤4. The manganese-sodium-tungsten-silicon composite oxide catalyst containing or not containing titanium set forth in the present invention is used for oxidative coupling of methane reactions, having excellent low-temperature catalytic activity and ethylene/propylene selectivity generation and reaction stability.

The invention relates to a technology for manufacturing artificial natural gas by methanating oxycarbide and provides a catalyst for methanating coke oven gas and a preparation method thereof. The catalyst is a gamma-aluminum oxide or a TiO2 carrier for carrying an active component and an addition agent, wherein the active component is Ni and the addition agent is composed of a first addition agent and a second addition agent; the first addition agent is a rare-earth element and the second addition agent is one or combination of more of Sr, Mn, V, Zr, Ce and Cr. The catalyst provided by the invention has good coke oven gas methanation activity and selectivity, and has the advantages of good high-temperature resistance, low-temperature activity and higher use space velocity; and the catalyst can be applied to various coke oven gas methanation processes including heat-insulating circulation, heat-insulating non-circulation, heat-exchange reactors and the like, and operation space velocities in the processes are more than 5000 per hour.

The invention relates to a transition metal doped cerium and titanium compound oxide catalyst for selective catalytic reduction of nitric oxide by ammonia, and a preparation method thereof. The catalyst in the invention is a transition metal (iron, tungsten and molybdenum) doped cerium and titanium compound oxide catalyst. The preparation method of the catalyst is a co-precipitation method, which comprises the following steps of: preparing mixed solution from cerium salt, titanium salt and salt corresponding to one or more transition metals of iron, tungsten and molybdenum, and continuously stirring for 3 to 15 hours at the temperature of between 50 and 150 DEG C by using one of ammonia water, sodium hydroxide, sodium carbonate, ammonium bicarbonate or urea; and filtering, washing, baking and calcining. In the invention, the adopted raw materials are non-toxic and harmless, the preparation method is simple and easy, the prepared catalyst has the characteristics of high catalytic activity, excellent N2 generation selectivity, broad operation temperature window, high space velocity reaction condition adaptability and the like, and is suitable for mobile sources represented by tail gas of diesel vehicles, as well as stationary source nitric oxide catalytic purification device represented by flue gas of coal fired power plants.

The invention relates to a Fe molecular sieve SCR (Selective Catalytic Reduction) catalyst for purifying NOx in acrylonitrile oxidization tail gas and a preparation method of the Fe molecular sieve SCR catalyst. A commercial ZSM-5 molecular sieve, a Y type molecular sieve, ferrierite or a beta molecular sieve is used as a carrier, 0.3-10.0 percent by mass of Fe<3+> is introduced to be used as an active component by adopting an immersion method or ion exchange method, and 0.5-8.0 percent by mass of M (lanthanum La or cobalt Co) is introduced to be used as a modification component. The SCR catalyst prepared by adopting the preparation method furthest realizes NO transformation and efficient catalysis removal of the NOx in the acrylonitrile oxidization tail gas under an oxygen enrichment condition. The preparation method provided by the invention has the advantages of simple process and good repeatability, and is beneficial to industrialized production.

The invention provides a CeTi#-[2]O#-[6] solid solution and its preparing method. The molecular formula is CeTi#-[2]O#-[6]. The process includes the following steps : the precursor of the cerous nitrate and titanium tetrachloride solution is served as raw material, the raw material is mixed and added into strong aqua ammonia, after depositing, aging, centrifuge washing, washing away Cl#+[-], vacuum freeze drying and baking, CeO#-[2]-TiO#-[2] powder is obtained, CeO#-[2]-TiO#-[2] powder is roasted at 650,750 and 800 degrees C., and crystallization of CeTi#-[2]O#-[6] is finished.The invention is suitable for removing NO#-[x] and SO#-[x] catalyst carrier.

The invention relates to a catalyst for removing nitrogen oxide through selective catalytic reduction for an automobile diesel engine adopting Ce2O3 and V2O5 double active compositions. The catalyst adopts scordierite honeycomb ceramics as a framework material, the Ce2O3 and the V2O5 as main active compositions, WO3 or MoO3 as an auxiliary catalyst composition, and TiO2 as a coating substrate, wherein the mass fraction of the main active compositions, namely the Ce2O3 and the V2O5, to the auxiliary catalyst composition WO3 or MoO3 to the coating substrate TiO2 is 1-3:6:12:85-93. The specific process comprises the following steps: preparing a TiO2 precursor solution; coating a TiO2 coating; coating an auxiliary catalyst; determining the loading of active compositions of oxides; and coating the main active compositions, namely the Ce2O3 and the V2O5. The catalyst replaces the V2O5 with high toxicity with the Ce2O3 with low toxicity, and reduces the environmental hazards of the catalyst, and the replaced catalyst has wider active temperature range, particularly greatly improves the low-temperature activity, and is particularly suitable for the traffic conditions of urban highways of China.

The invention discloses a flue gas denitrification catalyst with a wide activity temperature interval as well as a preparation method thereof. The flue gas denitrification catalyst comprises 65%-99.8% of carrier TiO2, 0.1%-10% of active component V2O5, 0.1%-10% of active component WO3 and 0.1%-15% of valence-variation metallic oxide. According to the invention, a ball mill is adopted for enabling the VWTiO2 catalyst and the valence-variation metal element oxide to be fully mixed mechanically, simplifies the technological process, reduces the energy consumption, and prevents the environment pollution; the prepared flue gas denitrification catalyst has a wide activity temperature interval and high capability of NOx removing activity and SO2 and H2O toxication resistance.