65results about How to "Improve low temperature catalytic activity" patented technology

The invention discloses modified Cu-SSZ-13 molecular sieves as well as a preparation method and the application thereof. The preparation method comprises the following steps: mixing an aluminum source, alkali metal hydroxides, a template agent, a silicon source and water to obtain initial sol; performing hydrothermal crystallization on the initial sol and then roasting to obtain M-SSZ-13 molecularsieves; performing ion exchange reaction between the M-SSZ-13 molecular sieves and ammonium salt and then roasting to obtain H-SSZ-13 molecular sieves; and performing ion exchange reaction with divalent copper salt and then roasting to obtain the modified Cu-SSZ-13 molecular sieves. The molecular sieves with different morphologies are synthesized in situ through adding the different alkali metalhydroxides. The modified Cu-SSZ-13 molecular sieves as well as the preparation method and the application thereof disclosed by the invention have the benefits that the different alkali metal hydroxides are directly added in the synthesis process, and the morphologies and the grain sizes of the molecular sieves are changed while alkali metal ions are introduced; each of the obtained modified Cu-SSZ-13 molecular sieves is high in degree of crystallinity and high in pure phase, and shows higher low temperature activity and nitrogen selectivity.

The invention discloses a catalyst for low-temperature catalytic combustion of volatile organic compounds and a preparation method thereof, belonging to the technical fields of chemical catalyst and preparation technology thereof. The catalyst contains, by mass percent, 0.1 to 1 % of an active ingredient Pb, 74 to 99.4 % of a carrier Al2O3 and 0.5 to 25% of an auxiliary agent RE2O3, wherein a specific surface area of a composite oxide RE2O3- Al2O3 is 80 to 326 m<2> / g. The catalyst provided by the invention is simple in preparation technology, easy to produce in large scale, and has a very high catalytic activity for low-temperature complete oxidation reactions of benzene, toluene, xylene, ethyl acetate, ethanol and propane. Provided is a novel and high-efficiency catalyst which can be used for purification treatment of the volatile organic compounds in fields of industrial exhaust or indoor pollution.

The invention relates to a Cu-Mn-based catalytic combustion catalyst for treatment of triphen waste gas and a preparation method thereof. The catalyst selects a Cu-Mn compound oxide as an active ingredient which loads on a compound carrier by an immersion method to obtain a supported non-noble metal compound oxide catalyst. The general formula of the catalyst is Cua(Mn)bO4 / A, wherein, a is 0-1 and b 0-2. In the catalyst, A is the compound carrier and Cua(Mn)bO4 is the active ingredient. The compound carrier is composed of 20-80 per cent of traditional carrier and 5-40 per cent of CeO2 (or ZrO2) by weight. The active ingredient is composed of 5-40 per cent of CuO, and 25-40 per cent of MnO by weight. The catalyst uses the shaped carrier to soak, which can eliminate the catalyst shaping technology, simplify the technology and reduce the cost. Simultaneously, rare earth oxygen storage ingredients are added in the compound carrier, which can greatly reduce the reaction temperature when organic substances are burning, improve catalyzing activity at low temperature, and extensively prolong the catalyzing life.

The invention relates to a mesoporous La0.8Sr0.2CoO3 loaded nanometer CeO2 catalyst as well as a preparation method and an application thereof. According to the mesoporous La0.8Sr0.2CoO3 loaded CeO2 catalyst disclosed by the invention, mesoporous perovskite La0.8Sr0.2CoO3 with a high specific surface area is used as a carrier, a cerium nitrate solution is used as a cerium source, and under alkaline conditions, CeO2 is loaded on the surface of mesoporous La0.8Sr0.2CoO3 by a hydrothermal method so that a loaded type catalyst is obtained. The preparation method comprises the specific steps of (1) performing mixing and hydrothermal loading on La0.8Sr0.2CoO3 which is used as a carrier and has a large specific surface area, and the cerium nitrate solution under the alkaline conditions for some time; and (2) washing the obtained mixture, filtering the washed mixture, drying the filtered mixture, and roasting the dried mixture so as to obtain a loaded type perovskite catalyst, wherein the La0.8Sr0.2CoO3 with the high specific surface area can be synthesized by using mesoporous SiO2 as a hard template. The mesoporous La0.8Sr0.2CoO3 loaded nanometer CeO2 catalyst as well as the preparation method and the application thereof disclosed by the invention have the advantages that the preparation method is simple, the cost of the mesoporous La0.8Sr0.2CoO3 loaded nanometer CeO2 catalyst is lower than that of a noble metal catalyst, all components in the catalyst are uniformly dispersed and interact, the growth of crystal grains is restrained, the obtained loaded type catalyst has good low temperature catalytic activity and good heat stability on oxidation of CO in the automobile tail gas, and the mesoporous La0.8Sr0.2CoO3 loaded nanometer CeO2 catalyst has good application prospects in the respects of treatment and purification of the automobile tail gas.

This invention relates to a method for preparing styrene by ethyl benzene dehydrogenation. Styrene is prepared at 450-550 deg.C, normal pressure, space velocity of 0.1-1.0h-1, and CO2 / ethyl benzene mol ratio of (10-30): 1 in the presence of Cr2O3 / Al2O3 catalyst. The method solves the problems of high energy consumption by steam diluter, or low catalyst performance at low temperatures caused by CO2 diluter. The method can be used for manufacture of styrene by ethyl benzene dehydrogenation.

The invention relates to a low-temperature water gas conversion catalyst under hydrogen rich reformed gas and a preparation method thereof, and belongs to the technical field of water gas conversion processes and catalysts. The active ingredient in the catalyst is Cu, the carrier is monoclinic phase ZrO2, and the auxiliary agent is one or more of acidic oxide and rare earth oxide. During preparation, the carrier is prepared by using a hydrothermal method, and then the active ingredient is carried by using a co-precipitation method. Compared with other copper-based conversion catalysts, the catalyst prepared by the method has high water gas conversion catalysis activity, and particularly the low-temperature water gas conversion activity of the catalyst is remarkably improved. For example, the catalyst with 25 percent of CuO can achieve the CO conversion rate of 53 percent at the temperature of 150 DEG C, and the CO conversion rate at the reaction temperature of 200 to 300 DEG C is over 90 percent.

The invention relates to a preparation method of a catalyst for preparing hydrogen from hydrogen sulfide. The preparation method comprises a first step (1) of reacting a pre-precipitating agent aqueous solution and a precipitating agent aqueous solution to form a pre-precipitating turbid solution; a second step (2) of adding a metal salt-water solution into the pre-precipitating turbid solution of the first step (1), a precipitant being formed by a reaction, filtering, washing, drying and calcinating the precipitant to obtain a metal salt oxide; and a third step of (3) performing a sulphur treatment on the metal salt oxide of the second step (2), and thus a product is obtained. Cations of the pre-precipitating agent can form a precipitant with anions of the precipitating agent, wherein the solubility product of the precipitant is larger than that of a precipitant formed by metal ions and the anions of the precipitating agent; the precipitating agent is a material capable of producing materials such as OH<->, CO3 <2-> or -OOCCOO- in water; and the metal is one or more selected from VIB group and VIII group transition metals. The catalyst prepared by the method provided by the invention is a bulk phase catalyst consisting of metal sulfur oxides, is low in cost, and has high catalytic activity.

The invention provides a carbon nanotube supported catalyst and a preparation method thereof as well as application of the carbon nanotube supported catalyst in low-temperature catalytic oxidation ofCO. The method comprises the following steps: mixing carbon nanotubes with impregnation liquid containing copper salt and manganese salt to obtain a mixture; drying the mixture and then roasting the mixture to obtain the carbon nanotube supported catalyst. The catalyst takes the carbon nanotubes as a carrier, and takes copper manganese complex oxide as an active ingredient supported on the carrier. The experimental results show that the catalyst prepared by the embodiment of the invention keeps relatively-high catalytic activity and stability for 0.1 to 0.5 percent of CO under the condition that the low temperature is 0 to 22 DEG C, is suitable for eliminating CO by low-temperature catalysis in a typical enclosed space and also can be used for a toxin filtering agent material of respiratory protective equipment for emergency rescue in the enclosed space. Besides, the preparation method of the carbon nanotube supported catalyst, provided by the invention, is simple; active ingredients are low in content, and the cost is relatively low.

The invention provides a methanation catalyst, a preparation method thereof and a method for using the methanation catalyst to prepare methane. The methanation catalyst is obtained by reducing metal hetero-atom doped NiAl hydrotalcite directly, the metal hetero-atom is doped into the NiAl hydrotalcite by replacing a nickel atom in a NiAl hyrotalcite crystal lattice, and the atomic radius ratio ofthe metal hetero-atom to the nickel atom is between 0.75 and 1.6, and the oxidation state is valence +2 and above. The obtained methanation catalyst has high specific surface area, permeability and pore volume, activation temperature is between 220 and 230 DEG C, the conversion rate of CO between 270 and 280 DEG C can reach 100%, the selectivity to CH4 can reach 97%, the product catalytic effect is stable, the service life is long, and the catalytic activity, the stability and the carbon deposition resistance of the methanation catalyst are all apparently superior to an existing commercializedcatalyst.

The invention relates to the technical field of ammonia decomposition, in particular to an ammonia decomposition catalyst and a preparation method and application thereof. The preparation method of the ammonia decomposition catalyst comprises the following steps: carrying out ball milling on ruthenium acetate, magnesium acetate and potassium acetate to obtain metal salt mixture powder; and roasting the metal salt mixture powder, and then performing hydrogen reduction to obtain the ammonia decomposition catalyst. According to the preparation method of the ammonia decomposition catalyst, specific raw materials including ruthenium acetate, magnesium acetate and potassium acetate are added in a one-pot mode, metal salt mixture powder is obtained through ball milling treatment, then the ammonia decomposition catalyst is prepared through roasting and hydrogen reduction, the steps are matched with one another, the particle size of ruthenium metal can be greatly reduced, and the low-temperature activity of the catalyst is improved.

The invention provides a catalyst, and a preparation method and an application thereof. The catalyst comprises an active component, a carrier and an auxiliary agent, wherein the active component is one or two selected from the group consisting of nickel and ruthenium; the carrier is potassium titanate; and the auxiliary agent is rare earth oxide. The catalyst has the following advantages: the potassium titanate is adopted as the carrier, and potassium ions are highly dispersed in the structure of titanium dioxide, so the performances of the potassium titanate used as a cocatalyst are easily and greatly improved; meanwhile, the potassium titanate has large specific surface area and facilitates dispersion of the active component, so the catalyst has high low-temperature catalytic activity and good ammonia decomposition catalytic effect.

The invention relates to a catalyst for preparing hydrogen from hydrogen sulfide and a preparation method thereof. The catalyst is a bulk phase catalyst consisting of metal sulfur oxides and the metal is one or more selected from VIB group and VIII group transition metals. The method for preparing the catalyst is simple, has relatively low cost, and has high catalytic activity when catalysts a reaction of hydrogen sulfide and carbon monoxide to prepare hydrogen and carbonyl sulfide.

The invention discloses a preparation method of a mesoporous supported CuO-LaCoO3 catalyst. The preparation method includes the steps: soaking mesoporous LaCoO3 into copper nitrate solution; calcining the mesoporous LaCoO3 soaking Cu ions for 4-6h in a muffle furnace at the temperature ranging from 400 DEG C to 600 DEG C to obtain the CuO-LaCoO3 catalyst. According to the method, needed raw materials are simple and easy to acquire, the mesoporous supported catalyst with the cost lower than that of a precious metal catalyst is prepared, components in the obtained CuO-LaCoO3 catalyst are uniformly dispersed and mutually acted, and the catalyst has good low-temperature catalytic activity and hot stability for CO in exhaust and can be used for the field of automobile exhaust catalysts. A support of CuO provides more active oxygen for an original catalyst, so that the low-temperature catalytic activity of the catalyst is improved.

The invention relates to a method for preparing a titanium dioxide-carbon nanotube composite carrier catalyst by a sol-gel method. Tetrabutyl titanate is used as a titanium dioxide carrier titanium source, carbon nanotubes treated by sulfuric acid or nitric acid are used as other components of the composite carrier and one or two of CeO2, Co3O4, Bi2O3 and NiO are used as active substances. The highly efficient persulfate catalyst is prepared from hydrolyzed gel of tetrabutyl titanate. The method has the characteristics of simple preparation process, good stability, good dispersion of active components, high low-temperature catalytic activity and good pH universality.

The invention relates to the technical field of catalysts and provides a wet oxidation catalyst and a preparation method and application thereof. The wet oxidation catalyst provided by the invention comprises a reductive carrier and a noble metal active component loaded on the reductive carrier, wherein metal elements in the noble metal active component and the reductive carrier are stabilized ina relatively low valence state, so that the activation and transfer of oxygen are facilitated, the oxidation of organic matters can be promoted, the catalytic activity of the catalyst at low temperature is improved, and the working temperature of the catalyst is reduced; the wet oxidation catalyst provided by the invention is high in low-temperature catalytic activity, and the catalytic activity at 100 DEG C can reach 100%. When the wet oxidation catalyst is applied to treatment of organic wastewater, the wastewater treatment temperature can be greatly reduced, so that the treatment difficultyof the organic wastewater is reduced, and the energy consumption is reduced.

The invention belongs to the field of catalysts, and in particular relates to a catalyst for synthesizing dimethyl carbonate and a preparation method thereof. The catalyst comprises 6-10wt% of active components and balance of a carrier, the active components are Bi2O3 and KOH, and the weight ratio of Bi2O3: KOH = 1: 2-4. The carrier is a zinc-iron composite metal oxide. In the invention, a hydrotalcite precursor of the carrier is produced by a coprecipitation method, and the active components bismuth oxide (Bi2O3) and potassium hydroxide (KOH) are directly loaded by wet impregnation without roasting, and then the catalyst is prepared by drying and roasting under appropriate conditions, so that ZnO and ZnFe2O4 in the prepared catalyst carrier have an appropriate proportion and interaction force, the active components are uniformly distributed, the interaction force between the active components and the carrier is moderate, and the catalyst as a whole has excellent low-temperature activity, stability and service life.

The invention relates to a preparation method of a CHA molecular sieve SCR monolithic catalyst. The preparation method is characterized by comprising the following steps of 1 CHA molecular sieve aqueous solution preparing; 2 adhesive preparing, wherein Al sol and Si Sol are prepared, mixed and stirred to be uniform at uniform velocity, and then the mixture is aged for 1-3 h to obtain an adhesive; 3 viscosity controlling, wherein the CHA molecular sieve aqueous solution and the adhesive are mixed to prepare molecular sieve coating size with the needed solid content, the molecular sieve coating size is stirred for 1-3 h, the viscosity of the molecular sieve coating size is tested and regulated to be 100-1,000 cP by regulating the pH value; 4 carrier coating, wherein after carrier coating is conducted, the surplus molecular sieve coating size is blown out, dried and then calcined for 2-3 h after the temperature is increased to 500 DEG C to 650 DEG C at the temperature increasing speed of 3-5 DEG C / min. According to the preparation method, a preparation technology of the CHA molecular sieve monolithic catalyst is greatly simplified, the size stability is improved, the size viscosity is easily controlled, and therefore the size can adapt to multiple coating processes.

This invention relates to a method for preparing styrene by ethyl benzene dehydrogenation. Styrene is prepared at 450-550 deg.C, normal pressure, space velocity of 0.1-1.0h-1, and CO2 / ethyl benzene mol ratio of (10-30): 1 in the presence of Cr2O3 / Al2O3 catalyst. The method solves the problems of high energy consumption by steam diluter, or low catalyst performance at low temperatures caused by CO2 diluter. The method can be used for manufacture of styrene by ethyl benzene dehydrogenation.

The present invention discloses a catalytic combustion catalyst for benzene waste gas treatment, the catalytic combustion catalyst is composed of a carrier and an active ingredient supported on the carrier, the catalytic combustion catalyst comprises 0.1-1% of Pd; 0. 1-1% of Ru; and 98-99.8% of gamma-Al2O3; the preparation method of the catalyst is as follows: 1) taking an organic palladium salt and an organic ruthenium salt to dissolve in an organic solvent; 2) adding the gamma-Al2O3 into the resulting solution of step 1), immersing and stirring, and transferring to a rotary evaporator to evaporate to dryness to obtain gamma-Al2O3 loaded with the organic palladium salt and the organic ruthenium salt; and 3) baking the gamma-Al2O3 loaded with the organic palladium salt and the organic ruthenium salt of the step 2) at 400-600 DEG C. The catalyst has a high low-temperature catalytic activity on the catalytic combustion reaction of volatile organic benzene compounds, preparation process is simple, and activity is superior, anti-poisoning performance is stronger, and the life is longer.

The invention discloses a wide-temperature type honeycomb denitration catalyst. The catalyst includes, by weight, 80-90 wt% of a carrier that is TiO2, 0-1 wt% of an active component A that is V2O5, 0-1 wt% of an active component B that is MnO2, 1-10 wt% of an auxiliary that is WO3, 1-3 wt% of an inhibitor that is CuCl, and 5-10 wt% of other components. The invention also relates to a preparing method of the catalyst. The catalyst includes the manganese dioxide, wherein the manganese dioxide is a low-temperature catalytic active component and can improve low-temperature activity of the catalyst. The catalyst includes the CuCl, wherein the extranuclear space of Cu<+> is free of a 4S electronic shell, the CuCl belongs to a Lewis acid, SO2 also belongs to a Lewis acid, and the CuCl and the SO2 are mutually exclusive, and therefore a SO2 / SO3 conversion ratio can be inhibited. The preparing method of the catalyst is simple, and is prone to industrialization.

The invention discloses a VOCs catalytic oxidation catalyst and a preparation method and application thereof. According to the catalyst, a hierarchical pore ZSM-5 molecular sieve serves as a carrier, transition metals Cu and Mn serve as active components, one or more of Ce, Nd and Co serve as auxiliaries, and the active metals and the auxiliaries are loaded into pore channels of the hierarchical pore molecular sieve through a step-by-step impregnation method; and steam treatment is then conducted to obtain the high-dispersion transition metal composite oxide catalyst. The well-developed pore channel structure of the hierarchical pore ZSM-5 molecular sieve provides the highly-dispersed surface for the active metal and the auxiliary, and the acidic center on the surface of the ZSM-5-molecular sieve provides the synergistic effect for the catalytic oxidation of VOCs, such that the VOCs catalytic oxidation activity of the catalyst is significantly improved; the catalyst is simple to prepare, adopts cheap raw materials, is suitable for mass production and industrial application, and has better application value and prospect.

The invention discloses an atom-doped modified double-shell integral hollow catalyst as well as a preparation method and application thereof. The catalyst is represented by the following general formula: N-ZSM-5 (at) M-ZSM-5, both M-ZSM-5 and N-ZSM-5 are metal atom-doped hierarchical pore molecular sieves with MFI structures, and N and M represent transition metal elements in Fe, Cu, Mn, Ni, Co, Ti and the like. The catalyst is a double-shell integral hollow catalyst, and an outer layer M-ZSM-5 and an inner layer N-ZSM-5 are tightly combined into a whole. The catalyst has relatively high specific surface area, mesoporous channels and diffusivity; and in the aspect of surface chemical properties, the catalyst has higher catalytic oxidation-reduction characteristic, sufficient surface active oxygen components and appropriate acidity. Meanwhile, the catalyst shows relatively high low-temperature catalytic activity, sulfur resistance, water resistance and chlorine poisoning resistance during catalytic oxidation of VOCs, and the stability of the catalyst is improved. The successful preparation of the catalyst can bring certain economic benefits and environmental benefits for low-temperature purification of complex organic waste gas, especially removal of CVOCs and impurity VOCs containing sulfur dioxide and the like.

The invention discloses a preparation method of a Pt-PbTiO3 nano-catalyst for CO catalytic oxidation. The preparation method is characterized in that a wet chemical reaction method is adopted; tetragonal perovskite Pb-TiO3 nano-particles synthesized by a hydrothermal method, H2PtCl6.6H2O, NaBH4 and deionized water are used as reaction raw materials; and through reducibility of NaBH4, Pt is reduced on the surfaces of the Pb-TiO3 nano-particles so that unstable Pt nano-particles are formed, and in follow-up drying, the unstable Pt nano-particles are completely crystallized so that the Pt-PbTiO3 nano-catalyst for CO catalytic oxidation is obtained. The preparation method has simple processes, can be controlled easily, has low pollution and a low cost and is suitable for large-scale production. The Pt-PbTiO3 nano-catalyst is stable, and has high purity, high CO catalytic oxidation efficiency and high low-temperature catalytic activity.

The invention discloses a honeycomb type low-temperature denitrification catalyst and a preparation method thereof. Through carbon nanotube obtained by an ion exchange method and hydrotalcite intercalated with metavanadate, Mn and Cu atoms on a laminated plate are distributed regularly and uniformly, and the active components of the catalyst are uniformly distributed and closely combined with a carrier. Under the influence of the dual electronic effect of the 'carrier' and the laminated plate, the catalyst has a catalytic effect that an ordinary supported catalyst cannot achieve.

The invention relates to a nanometer agglomerated sheet-shaped mordenite catalyst and a preparation method thereof. A purpose of the present invention is mainly to overcome the problems of slow diffusion speed and unsmooth diffusion channel in the actual application of conventional spheres and other blocky agglomerated nanometer materials. According to the technical scheme, the catalyst comprises,by weight, A) 5-95% of a nanometer aggregated sheet-shaped mordenite material; B) 0.001-3% of a transition metal; and C) 2-80% of a binder. With the technical scheme, the problems in the prior art are well solved. According to the present invention, the cost of the technology can be controlled, the excellent reaction performance can be provided in the high space velocity aromatic hydrocarbon conversion reaction, the occurrence of aromatic hydrocarbon polymerization, cracking and other side reactions can be effectively inhibited, and the catalyst can be used in the industrial production of aromatic hydrocarbon conversion.

The invention discloses an Au nano catalyst for exhaust purification of an internal-combustion engine and a preparation method thereof, and belongs to the technical fields of automobile emission control and environmental protection. The catalyst uses a metal oxide nanowire as a carrier, precipitates on the top end of the carrier in a way of Au nanoparticles, and has a particle diameter of 5-10 nm. A vapor deposition method employing a vapor-liquid-solid mechanism is used to prepare the Au nano catalyst. The method comprises the following steps: (1) preparing Au nano lattices on a quartz substrate by a magnetron sputtering technology; (2) mixing a graphite powder and a metal oxide powder; (3) designing a double-heating tank chemical vapor deposition system, and introducing inert gas; (4) controlling the temperature of a pipe-type heating furnace; and (5) controlling a reaction time. The catalyst has high low-temperature catalytic activity and can replace noble metals such as Pt, Pd and Rh to be used in the field of exhaust purification of internal-combustion engine.

The invention discloses an Rb ion substituted OMS-2 catalyst as well as a preparation method and application thereof. The catalyst comprises an OMS-2 carrier and reactive metal; the reactive metal isRb ions; the Rb ions are loaded in pore canals of the OMS-2 carrier; and a molar ratio of the Rb ions to Mn in the OMS-2 carrier is (0.001-0.5) to 1. The preparation method comprises the following steps of by taking potassium permanganate as an oxidant and manganese nitrate as a reducing agent, introducing an Rb-containing salt solution with a certain concentration into a system, and adopting a mild one-step hydrothermal synthesis method to synthesize the Rb ion substituted OMS-2 catalyst (RB-OMS-2). Through a strategy of substituting K<+> in the pore canals of an OMS-2 molecular sieve by theRb ions, the activity of lattice oxygen in the OMS-2 catalyst is effectively improved, so that the activity of catalytically purifying VOCs is remarkably improved. By adopting the catalyst, the benzene catalytic purification efficiency exceeds 90 percent at 220-240 DEG C.

The invention provides a composite catalyst for removal of stink and resource recycling of sulfur-containing compounds. The composite catalyst comprises the following components by weight percentage:50-90% of a carrier, 5-30% of a metal oxide and 5-30% of a reducing agent. The invention also further provides a preparation method and application of the composite catalyst for removal of stink and resource recycling of sulfur-containing compounds. According to the composite catalyst for removal of stink and resource recycling of sulfur-containing compounds, the preparation method and applicationthereof provided by the invention, the composite catalyst is economical, energy-saving, environment-friendly, and high in purification efficiency, can be used repeatedly, and can be used under complicated conditions with wide reaction temperature range, violent or frequent fluctuation of malodorous gas concentration, is very suitable for the purification field of stationary source malodorous gases containing methyl mercaptan, dimethyl sulfide, dimethyl disulfide, carbon disulfide and other organic sulfur, and has broad practical industrial application prospects.