51results about How to "Wide reaction temperature window" patented technology

The invention discloses a catalyst for purification of waste incineration flue gas. The catalyst takes vanadium oxide, platinum oxide and tungsten oxide as active components, gamma-alumina, titanium oxide and carbon nanotubes as carriers and one or more of manganese oxide, iron oxide, copper oxide, tin oxide and cerium oxide as active aids. The catalyst has the functions of decomposing dioxin andchlorobenzene compounds and functions of denitration and sulfur resistance and still has excellent removal capacity for dioxin and NOx at lower temperature. The invention also discloses a preparationmethod of the catalyst for purification of waste incineration flue gas. The preparation method has the advantages of being simple to operate, convenient, controllable and suitable for mass industrialproduction.

The invention discloses a high-efficiency denitration catalyst and a preparation process thereof. The catalyst is a cerium bismuth aluminum composite oxide, wherein based on the molar ratio of metal elements, the molar ratio of cerium to aluminum is 0.1-1.0, and the molar ratio of bismuth to aluminum is 0.1-1.0. The catalyst is prepared by utilizing a treatment process of integrating a homogeneous co-precipitation method and a hydrothermal method, after-treatment is performed by utilizing the technical means of azeotropic distillation, and solid solution can be formed when the cerium and bismuth oxides are positioned in a highly dispersed state in the metal compound oxide. The high-efficiency denitration catalyst prepared by the invention can achieve excellent denitration activity, reaction stability, water resistance and sulfur tolerance in a temperature range of 200-400 DEG C.

The invention discloses a preparation method of a tung oil-based aqueous polyurethane coating. The preparation method comprises the following steps: mixing tung oil, carboxylic acid, an acid catalyst and a hydroxylation reagent in proportion, and heating the obtained mixture to 35-45 DEG C; dropwise adding a hydrogen peroxide solution while intense stirring, controlling the dropwise adding speed to keep the reaction carried out at 40-65 DEG C, and keeping the reaction for 3-5 h after the dropwise addition is finished; standing and layering the obtained reaction solution after the reaction ends, separating the obtained water phase, neutralizing the water phase, washing the neutralized water phase with water, and carrying out reduced pressure distillation to obtain tung oil polyol; and uniformly mixing the tung oil polyol, a hydrophilic modifier and acetone in proportion, adding diisocyanate, carrying out a reaction at 50-70 DEG C for 2-5 h, cooling the obtained reaction product to room temperature, adding a neutralizer to form a salt, adding a diamine chain extender and deionized water mixed solution, carrying out a chain extension reaction until no free isocyanate radicals exist, and carrying out reduced pressure distillation to remove the acetone in order to obtain the tung oil-based aqueous polyurethane coating. The preparation method has the advantages of effective improvement of the hydrophobicity and the moisture resistance of the aqueous polyurethane coating, and renewable and nontoxic raw materials.

The invention relates to a mixed rare-earth denitration catalyst and a preparation method thereof. An active component of the denitration catalyst is a double-active component composed of mixed rare-earth oxide and transition element oxide. The catalyst has the advantages of high catalytic efficiency, wide reaction temperature window and the like due to the synergistic effect between the mixed rare-earth oxide and between the rare-earth oxide and the transition element oxide. A preparation technology adopts an immersion method to manufacture and has the advantage of simple technology, wide raw material sources, low cost and the like. The mixed rare-earth oxide catalyst provided by the invention is mainly applied to the aspect of purifying industrial waste gas, and is especially used for the aspect of flue gas denitration. The mixed rare-earth denitration catalyst can be used for middle-temperature and low-temperature flue gas denitration of coal-fired power plants and can also be used for the field of low-temperature flue gas denitration of an industrial source.

The invention relates to a conducting flue gas denitration catalyst and a preparation method thereof. The conducting flue gas denitration catalyst is prepared from the following raw materials in percentage by weight: 60 to 90 percent of titanium dioxide, 3 to 9 percent of tungsten trioxide, 0.1 to 2 percent of vanadium pentoxide, 1 to 5 percent of silicon dioxide, 1 to 5 percent of rare earth, 3 to 10 percent of C fibers and the balance of a forming agent. The conducting flue gas denitration catalyst has a wire function, implements low-temperature catalysis, has high denitration efficiency, a low SO2/SO3 conversion rate, a low ammonia escape rate, wear resistance, high intensity, a long chemical service life and a long mechanical service life and has low output of domestic sewage.

The invention discloses a deep denitration process for a supercritical carbon dioxide coal-fired boiler, belonging to the technical field of NOx emission reduction. The deep denitration process comprises the following steps: three-stage ammonia injection denitration, wherein an ammonia injection combustor is used for injecting a fuel and an amino reducing agent into a main combustion area of a combustor in a boiler to form an annular high-temperature low-oxygen reduction area with a temperature of 850-1400 DEG C, and a reduction reaction is carried out in the annular high-temperature low-oxygen reduction area to achieve first-stage denitration, and a second-stage ammonia injection device and a third-stage ammonia injection device are used for respectively injecting an amino reducing agentto a main combustion area at the upper part of the high-temperature low-oxygen reduction area and a burnout area behind burnout air to realize second-stage denitration and third-stage denitration; anddedusting, desulfurization and denitrification, wherein SCR denitrification is conducted on the flue gas in a dedusting and denitrification unit, and then the flue gas is cooled to 70-90 DEG C and then sent into the boiler for circular denitrification treatment. The defect that the denitration degree is insufficient due to the fact that the temperature of the supercritical carbon dioxide coal-fired boiler is high in the prior art is overcome, deep staged denitration in the boiler is achieved through the three-stage ammonia injection denitration process, the temperature in the boiler is effectively reduced through low-temperature flue gas recirculation combustion, generation of thermal NOx is reduced, and deep denitration of the supercritical carbon dioxide coal-fired boiler is achieved.

The invention provides a preparation method and application of a low temperature denitration Ni-based composite oxide cellular monolithic catalyst, and belongs to the technical field of environment catalysis and purification. The cellular monolithic catalyst mainly comprises an active component, a binding agent and an extrusion aid. The active component is a Ni-based composite metal oxide, the binding agent is prepared from pseudo-boehmite, a silicon oxide and dilute nitric acid, and the extrusion aid is sesbania powder. The monolithic catalyst has the good low temperature denitration performance and wide temperature operation window, the NOx conversion rate can reach 80% or above in the temperature range of 80-320 DEG C, and the catalyst has the high operation stability, good sulfur and water resistance and high application value and application prospect.

The invention discloses a copper-iron-containing bimetal porous catalyst and a preparation method thereof. The catalyst composition is expressed as CuFezSixAlO2(x+), z is equal to 0.1 to 5 percent, x/is equal to 1 to 50, z/ is equal to 0.1 to 1. The preparation method comprises the following steps: taking a Y molecular sieve as a carrier and taking copper iron bimetallic salt as an active ingredient precursor to prepare an aqueous solution; introducing the copper iron bimetallic active ingredient by using a liquid phase ion exchange method, and regulating the weight percentage of copper ironbimetal to 0 to 5 percent by controlling exchange times and time; drying and calcining samples to form catalyst powder; then carrying out direct high-pressure extruding molding or coating on the powder to the substrate surface with a fixed shape to obtain an integral catalyst. When the copper-iron-containing bimetal porous catalyst is used in the reaction of selective catalytic reduction of nitrogen oxide by ammonia, the reaction temperature is 150 to 500 DEG C, the ammonia is used as a reducing agent, the total flow of gas is controlled at 100 to 400ml/min and the airspeed is 10000 to 128000h<-1>. The purification efficiency of the nitrogen oxide is 90 to 100 percent.

The invention relates to a low-temperature denitration catalyst and a preparation method and application thereof, and the method comprises the following steps: (1) dissolving manganese nitrate, ceriumnitrate and fuel in deionized water to obtain a mixed solution; (2) adding titanium dioxide into the mixed solution, and uniformly stirring to obtain a product; and (3) placing the obtained product in a pre-preheated combustion chamber for rapid combustion, then continuously roasting for a certain time, and finally grinding to obtain the Mn-Ce-Ox/TiO2 low-temperature denitration catalyst which isused for NH3-SCR reaction. Compared with the prior art, the preparation method has the advantages that the operation is simple, the prepared catalyst is porous and fluffy, the low-temperature denitration activity is better, the reaction temperature window is wider, the water resistance and sulfur resistance are better, and the like.

The invention discloses a low hydroxyl value tung oil polyol preparation method, which comprises: (1) mixing tung oil, carboxylic acid, a catalyst and a hydroxylating reagent according to a certain ratio, heating to a temperature of 35-45 DEG C, adding a hydrogen peroxide solution in a dropwise manner under a vigorous stirring condition, maintaining the reaction temperature at 40-65 DEG C, maintaining the reaction temperature for 3-5 h after completing the adding, carrying out standing layering after completing the reaction, separating to obtain a water phase, neutralizing, carrying out water washing, and carrying out pressure reducing distillation to obtain tung oil polyol; and (2) mixing the tung oil polyol prepared in the step (1) and an alkaline catalyst according to a certain ratio, heating to a temperature of 90-140 DEG C, adding an epoxide, carrying out a polymerization reaction, and after completing the reaction, carrying out acid neutralizing, water washing and pressure reducing distillation to obtain the low hydroxyl value tung oil polyol. According to the present invention, the prepared low hydroxyl value tung oil polyol has the hydroxyl value of 30-100 mgKOH/g, the acid value of less than 1.0 mgKOH/g, the moisture content of less than 0.1 wt% and the yield of more than 90%, and is suitable for the preparation of polyurethane soft foam materials, polyurethane elastomers, and the like.

The invention discloses a tung oil-based polyol synthesis method, which comprises: mixing tung oil and a hydroxylating reagent according to a certain ratio, and heating to a temperature of 35-45 DEG C; mixing a hydrogen peroxide solution accounting for 40-60% of the total adding amount, carboxylic acid and an inorganic acid catalyst under vigorous stirring, adding the obtained mixture to the reaction system in a dropwise manner, slowly adding the remaining hydrogen peroxide solution in a dropwise manner after completing the adding of the mixture, maintaining the reaction temperature at 40-65 DEG C by controlling the adding rate, and maintaining the reaction temperature for 3-5 h after completing the adding; and carrying out standing layering after completing the reaction, separating to obtain a water phase, neutralizing, carrying out water washing, and carrying out pressure reducing distillation to obtain the tung oil-based polyol. According to the present invention, the conjugated double bond of tung oil can improve the reactivity of the epoxy group, such that the hydroxylating reagent is added while the epoxidation is performed so as to effectively avoid the occurrence of the cross-linking side reaction and efficiently synthesize the tung oil-based polyol product; and the prepared tung oil-based polyol has the hydroxyl value of 120-270 mgKOH/g, the acid value of less than 1.0 mgKOH/g, the moisture content of less than 0.1 wt% and the yield of more than 92%, and can be used for the preparation of polyurethane materials.

The invention provides a Fe-Mn-Ce/titanium-containing blast furnace slag denitration catalyst . The Fe-Mn-Ce/titanium-containing blast furnace slag denitration catalyst provided by the invention has the characteristics of excellent low-temperature catalytic activity, wide reaction temperature window and the like, the price cost of the used raw materials is lower, and compared with a rare earth metal-based catalyst, the Fe-Mn-Ce/titanium-containing blast furnace slag denitration catalyst has obvious advantages. The Fe-Mn-Ce/titanium-containing blast furnace slag denitration catalyst provided by the invention has an obvious anti-poisoning effect on heavy metals such as PbO, PbCl2 or PbSO4. When the catalyst is applied to the field of selective catalytic reduction flue gas denitration, the actual service life of the catalyst can be prolonged, and the use cost is reduced. And the idea of turning waste into wealth is adopted, so that the blast furnace by-product titanium-containing blast furnace slag can be utilized to a greater extent, resources are saved, the pollution to the environment is reduced, and good social benefits are achieved.