111results about How to "Wide active temperature window" patented technology

The invention relates to the environmental protection field of flue gas treatment of gas-fired boilers, in particular to a surface deposition honeycomb flue gas denitration catalyst and a preparation method thereof. The catalyst comprises a honeycomb framework which takes clay, soot dust or slag as a substrate; TiO2 is taken as an active carrier; WO3 and V2O5 serving as active ingredients are loaded on the TiO2 active carrier, and are uniformly distributed in the honeycomb framework; and the catalyst comprises the following components in percentage by weight: 60-80 percent of clay, soot dust or slag, 13-33 percent of TiO2, 1-5 percent of WO3 and 0.1-2 percent of V2O5. By transferring an ignition lost transition carrier, highly dispersion of catalyst nanoparticles on a molding catalyst pore cannel and an outer surface is realized, and the utilization ratio and catalytic activity of the active ingredients are increased greatly.

The invention relates to a plate-type catalyst capable of simultaneous denitration and demercuration and a preparation method thereof and belongs to the field of air pollution control. According to the catalyst, fiberglass, active components, a bonder, an assistant and a carrier are used as catalyst paste, and a framework is coated with the catalyst paste, wherein the active components are V2O5 and MoO3, or V2O5 and WO3, and the carrier is TiO2; in the catalyst paste, the mass ratio of carrier, to fiberglass, to catalyst active component V2O5, to catalyst active component MoO3 or WO3 to bonder to assistant is 100:(1-8):(0.1-5):(2-10):(0.5-5):(0-15). The catalyst simultaneously complete selective catalytic reduction of NOx and catalytic oxidation of Hg<0> in an SCR reactor, the generated Hg<2+> is washed and solidified in desulphurization gypsum in a follow-up desulphurization device through the smoke wet process, and the simultaneous removal of NOx and HgO is realized on the condition that no smoke purification device is added.

The invention discloses a flue gas denitration catalyst. The catalyst comprises a carrier and a catalytic activity component, wherein the catalytic activity component is manganese, cobalt and cerium composite oxide, wherein the molar ratio of the manganese element to the cobalt element to the cerium element is 1:0.1-1:0.1-1. A preparation method of the flue gas denitration catalyst comprises the following steps of: (1) taking a soluble manganese salt, a soluble cobalt salt and a soluble cerium salt, wherein the molar ratio of the manganese element to the cobalt element to the cerium element is 1:0.1-1:0.1-1, dissolving the salts in deionized water, and adding ammonia water to adjust the pH value to between 5 and 7; (2) soaking a carrier in aqueous solution of citric acid, diluted hydrochloric acid or diluted nitric acid for 24 to 48 hours, drying the carrier, soaking the carrier in the solution of the step (1), standing the carrier for 24 hours and drying the carrier; and (3) roastingthe prepared sample in step (2) in air, and cooling the sample. The flue gas denitration catalyst has the advantages of simple preparation method, high poisoning resistance, no secondary pollution toenvironment, wide activity temperature window, low activity starting temperature and the like.

The invention discloses a monolithic SCR (Selective Catalytic Reduction) honeycomb catalyst for processing diesel exhaust and a preparation method of the catalyst. The catalyst comprises a honeycomb ceramic carrier and a coating; the coating coats a honeycomb hole, and the coating consists of a ZrO2 / TiO2 composite oxide carrier and catalyst active components. The ZrO2 / TiO2 composite oxide carrier comprises the following components in percentage by weight: 5wt%-20wt% of ZrO2 and 50wt%-85wt% of TiO2. The catalyst active components comprise the following components in percentage by weight: 1wt%-5wt% of V2O5, 1wt%-10wt% of WO, 1wt%-5wt% of Fe2O3, 1wt%-5wt% of CuO, 1wt%-10wt% of rare earth metal oxide and the balance of an adhesion agent. The preparation method of the catalyst comprises the following steps: firstly preparing the ZrO2 / TiO2 composite oxide carrier, subsequently preparing a vanadium-tungsten-zirconium-titanium powder catalyst, then dispersing the vanadium-tungsten-zirconium-titanium powder catalyst in other components to prepare a catalyst slurry; and then coating the honeycomb ceramic carrier with the catalyst slurry, drying and roasting, and then preparing the monolithic SCR honeycomb catalyst. The monolithic SCR honeycomb catalyst is suitable for purifying diesel exhaust NOx and has the characteristics of wide active temperature window at 160-550 DEG C, high NOx removal rate, strong antitoxic performance, long service life and simplicity in preparation.

The invention belongs to the field of the utilization of blast furnace slag, and particularly relates to a preparation method of a novel SCR smoke denitrification catalyst adopting titanium-containing blast furnace slag as a carrier. The preparation method comprises the following steps: a, pretreating the titanium-containing blast furnace slag; and b, preparing the catalyst. The preparation method of the catalyst is simple and easy in operation, high in blast furnace slag utilization rate, capable of effectively solving the resource waste and environmental pollution problem caused by the extensive application of the titanium-containing blast furnace slag and capable of enlarging the application field of the blast furnace slag; the catalyst prepared in the method is high in activity, wide in active temperature window and capable of maintaining relatively high denitrification activity at the temperature of 160 to 260 DEG C.

The invention provides a compounded denitration catalyst and a preparation method thereof, and belongs to the technical field of environment catalysis and atmospheric pollution controlling. The catalyst adopts titanium dioxide as a carrier, cerium dioxide as a main active component, and molybdenum trioxide as secondary active component performing a synergistic effect, and is prepared according to a stepped impregnation method. The compounded denitration catalyst is characterized in that due to the adding of molybdenum trioxide, the denitration performance of cerium-titanium catalyst is improved obviously, the active temperature window is widened, and the water resistance of the catalyst is also improved obviously. The method for reducing nitrogen oxides comprises the following steps: filling the catalyst into a fixed bed reactor; controlling the reaction temperature range to be 250 to 400 DEG C; and taking ammonia as a reducing agent. The cerium-molybdenum-titanium compounded catalyst prepared according to the invention is 12,8000 per hour in space velocity, and can purify nitrogen oxides with the efficiency ranging from 83 to 98 percent at the temperature ranging from 250 to 400 DEG C.

The invention discloses a method for preparing a molecular sieve SCR catalyst, and the catalyst prepared therethrough. Several molecular sieves are mixed, and then undergo ion exchange modification treatment by a transition metal or a rare earth metal, Fe is loaded through isopyknic impregnation, and Cu is loaded through one-stage or multistage liquid ion exchange. A technology for modifying the stable molecular sieve mixture with the transition and rare earth metals, a technology for loading Fe by the isopyknic impregnation process and a technology for loading Cu by the one-stage or multistage liquid ion exchange are combined, and a catalysis material obtained through stable and effective modification and loading control is applied to a carrier matrix after being blended to form a slurryin order to prepare the monolithic catalyst; results of fresh sample activity test and hydrothermal aging test show that the catalyst has a wide active temperature window and excellent hydrothermal aging resistance, and the N2O generation amount of the catalyst prepared in the invention is significantly lower than that of previous catalysts of the same type.

The invention relates to a copper-based molecular sieve catalyst used for diesel engine NOx removing using low-temperature NH3-SCR and a preparation method of the copper-based molecular sieve catalystand belongs to the technical field of diesel engine tail gas pollutant control. The catalyst uses silicon-aluminum-phosphorus-oxygen tetrahedron (SAPO-34) as the carrier, Cu as the main active component and Ce as the promoter component. Chemical element proportion used during the preparation is 1Al:1P:0.25Si:0.06Cu-TEPA:(0.01 / 0.04 / 0.06 / 0.08)Ce:1.6PA:40H2O. The preparation method specifically includes: synthesizing Cu-TEPA; loading the copper serving as the main active component, determining the loading capacity of the Ce serving as the promoter, loading the Ce serving as the promoter, and performing one-pot synthesizing of the CuCe-SAPO-34 integral structure. The copper-based molecular sieve catalyst and the preparation method thereof have the advantages that the copper and cerium molecular sieve catalyst is used to replace a traditional vanadium-based catalyst, the environmental harm of the catalyst is lowered, low-temperature activity and high-temperature and low-temperature selectivity are increased greatly, the catalyst can effectively reduce NOx in the wide temperature window of 150-550 DEG C, and the catalyst is high in sulfur resistance and hydrothermal aging resistance andapplicable to high-sulfur diesel oil and city road traffic conditions of China.

The invention discloses a titanium-based nano-composite metal oxide catalyst and a preparation method thereof, belonging to the technical field of control on exhaust contaminants in diesel engine tail gas. In the invention, the titanium-based nano-composite metal oxide catalyst is prepared by taking TiO2 as a carrier and taking metal oxides (VOx, MnOx and CeOx) as active components by adopting a self-propagating high-temperature synthesis (SHS) method, wherein the molar percentage of the TiO2 is 80-95%, the molar percentage of the VOx is 2-20%, the molar percentage of the MnOx is 2-10%, and the molar percentage of the CeOx is 2-10%. The preparation method of the titanium-based nano-composite metal oxide catalyst comprises the following steps of: preparing a TiO(NO3)2 precursor solution; determining the loads of the active components of the metal oxides; preparing a precursor solution of the active components of the metal oxides; and preparing the catalyst by SHS. The catalyst prepared by the method disclosed by the invention has the advantages of large specific surface area, large pore volume, proper pore size distribution and low degree of crystallization, all active species are highly dispersed and are interactive, the catalyst has higher NOx removing rate and N2 selectivity in a wide temperature window at 100-450 DEG C, and the catalyst has strong anti-sulfur and anti-water poisoning performance and is suitable for treating NOx in diesel engine tail gas of automobiles and ships.

The invention relates to a preparation method for a high-temperature flue gas denitrification catalyst and belongs to the technical field of flue gas denitrification. The preparation method comprises the following two steps: preparing a precursor; and preparing a catalyst. According to the technical scheme, the preparation method comprises the steps: by taking V2O5 as a main active component and Nb2O5 and MoO3 as an auxiliary active component, preparing the precursor of V2O5, Nb2O5 and MoO3; and then mixing the precursor by titanium tungsten powder taking TiO2 and WO3 as main components through extrusion molding, drying and water removal and roasting processes to prepare the catalyst. The problem that the SCR denitration efficiency is relatively low when the flue gas temperature of a coal-fired power plant is 280-300 DEG C is solved. Moreover, in the catalyst preparation process, a microwave drying technology is adopted to overcome the defect of cracking and uneven size distribution caused by temperature gradient in a conventional drying technology, so that the drying time is shortened and the production efficiency is improved. The invention further relates to a denitrification catalyst prepared by the method, so that the low-temperature activity of the catalyst is improved and the active temperature window is expanded, and the preparation method has beneficial technical effects.

The invention relates to a preparation method of a rod-shaped cerium oxide-supported samarium-manganese composite oxide catalyst. The method comprises: S01, carrier preparation: a, mixing a cerium nitrate hexahydrate solution and a sodium hydroxide solution through stirring to obtain a first mixed solution, b, transferring the first mixed solution into a reactor and carrying out high temperature treatment and c, carrying out high temperature roasting on a sample subjected to high temperature treatment to obtain a rod-shaped cerium oxide carrier, and S02, catalyst preparation: d, preparing a second mixed solution of samarium nitrate and manganese nitrate, e, dipping the rod-shaped cerium oxide carrier in the second mixed solution and f, carrying out high temperature roasting on the soaked sample to obtain an oxidation state catalyst. The catalyst is in a wide temperature range of 100-200 DEG C and the purification efficiency of nitrogen oxide is 90% or more.

The invention belongs to the field of denitration catalysts, and discloses a low-temperature SCR denitration catalyst based on kaoline and a preparation method of the catalyst. The SCR denitration catalyst comprises a carrier and active components attached to the carrier, the carrier is the kaoline, and the active components are manganite and cerium oxide. The invention further discloses the preparation method of the above SCR denitration catalyst. The preparation method comprises the following steps that (a) manganous nitrate and cerous nitrate are selected as raw materials, mixed and dissolved in deionized water to form steeping liquid; (b) the kaoline is added into the steeping liquid, stirring is conducted at the indoor temperature, and suspension liquid is obtained; (c) the suspensionliquid is subjected to magnetic stirring to be in a sticky state, a mixture in the sticky state is obtained, dried and roasted, and the required catalyst is obtained. According to the catalyst and the preparation method, the cost of the catalyst is reduced, the catalysis efficiency is high, and a guidance effect is achieved on research for a low-temperature denitration catalyst.

The invention relates to a catalyst, and especially relates to an SCR catalyst for ship diesel engine post-treatment, and a preparation method thereof. The catalyst adopts a ZSM-5 molecular sieve with a high specific surface area as a supporter, and adopts vanadium, tungsten, copper, manganese and cerium metal elements as active components. The specific surface area of the ZSM-5 molecular sieve with a high specific surface area is above 500m<2> / g, and the specific pore volume of the ZSM-5 molecular sieve with a high specific surface area is above 0.6mL / g. The preparation method comprises the following steps: preprocessing ZSM-5 molecular sieve powder with a high specific surface area to remove superfluous water in the molecular sieve powder; mixing the active components with water to obtain an active component solution, wherein the volume of water is the product of the mass of the ZSM-5 molecular sieve and the specific pore volume of the ZSM-5 molecular sieve; adding the active component solution to the preprocessed ZSM-5 molecular sieve with a high specific surface area in a dropwise manner, and continuously stirring to obtain a viscous material; and heating the viscous material for drying, and calcining; and cooling. The catalyst has the advantages of high catalysis activity, high hydrothermal stability, high sulfur resistance, and wide active temperature window, and can guarantee that denitration of tail gas of ship diesel engines meets requirements of Tier III standards.