75results about "Aluminosilicate zeolite type-A" patented technology

The invention provides a method for recovering fluorine resources by using fluorine-containing silicon powder and synthesizing an A-type molecular sieve, which comprises the following steps: A) mixing the fluorine-containing silicon powder with a sodium hydroxide solution, and heating for reaction to obtain a clear solution and a precipitate sodium fluoride; silicon and sodium in the settled solution are metered by SiO2 and Na2O, and the molar ratio of SiO2 to Na2O is 1.9-2.4; b) mixing sodium aluminate with a sodium hydroxide solution to obtain an alkaline solution of the sodium aluminate, mixing the settled solution in the step A) with the alkaline solution of the sodium aluminate, and stirring to obtain a gel solution; and C) heating and crystallizing the gel solution to obtain the A-type molecular sieve. The removal of organic impurities in the fluorine-containing silicon powder, the efficient separation of fluorine and silicon and the synthesis of the 4A molecular sieve with high purity and few crystal defects are completed through the preparation of low-modulus sodium silicate, filtration and separation and the removal of a small amount of residual fluorine in sodium silicate gel.

The application relates to the technical field of explosion suppression agent preparation, in particular to a novel inorganic low-silicon-aluminum-ratio explosion suppression material and a preparation method thereof.The steps of the preparation method comprise the following steps: placing dried molecular sieves in an alkali solution, placing the molecular sieves in a magnetic stirrer and stirring intensively, centrifugally separating the stirred sample, washing the sample with deionized water until neutral, drying the sample in a blast drying oven at 120 DEG C for 24 h, grinding the sample in a mortar for 10 min, and sieving to obtain explosion suppression powder.The prepared inorganic low-silicon-aluminum-ratio explosion suppression material has the advantages of high efficiency, low cost, non-toxicity and harmlessness, and can be used for industrial production and applied to the field of methane explosion suppression.

A utilization method of FAU molecular sieve crystallization mother liquor, characterized in that, comprising: uniformly mixing FAU molecular sieve mother liquor, silicon source, inorganic alkali, water and aluminum source to obtain a type molecular sieve synthesis system mixture with a molar ratio of SiO2 / Al2O3=1.85-1.99, Na2O / SiO2=1.0-1.6, H2O / SiO2=45-65; aging and hydrothermal crystallization are performed on the mixture, and the product is recovered to obtain a type molecular sieve and a type molecular sieve filtration mother liquor; or further uniformly mixing the type molecular sieve filtration mother liquor and an aluminum-containing compound, stirring at 160-200 DEG C for 2-8 hours to obtain a recycled aluminum source with a SiO2 content of 50-300 ppm; uniformly mixing silicon source, inorganic alkali, recycled aluminum source and water to obtain a FAU molecular sieve synthesis system mixture, aging and hydrothermal crystallization are performed on the mixture, and the product is recovered to obtain a FAU molecular sieve and a FAU molecular sieve crystallization mother liquor. The method can not only completely recycle the FAU molecular sieve mother liquor, avoid waste water discharge, reduce the consumption of inorganic alkali and deionized water, and significantly reduce the production cost, but also can be flexibly used for preparing FAU molecular sieve and / or a type molecular sieve.

The present invention relates to a method for the preparation of monoliths of zeolite A, allowing the 3D printing of zeolite precursor gels, the product crystallization taking place contemporary to the component solidification, and to form monolithic objects with optimized designs in terms of the properties required for each application.

To provide a membrane reactor capable of improving yield of a target product by progressing efficiently a catalyst reaction, in a reaction controlled by chemical equilibrium.SOLUTION: Concerning a membrane reactor for performing a reaction controlled by chemical equilibrium, the membrane reactor has a separation membrane for selectively and continuously separating, from reaction liquid, a by-product generated by the reaction. By selectively and continuously separating the by-product from the reaction liquid, the chemical equilibrium is shifted and the reaction is furthermore progressed.SELECTED DRAWING: None

A high-purity artificial zeolite is industrially mass produced by carrying out osmosis treatment of fly ash in an alkaline aqueous solution, subsequently carrying out the osmosis treatment again with an acidic aqueous solution of pH 1.0 or less obtained by adding acid to the osmotic aqueous solution of fly ash, then performing solid-liquid separation while water wash and dewatering in a centrifuge, thereby synthesizing a starting composition, and performing hydrothermal reaction treatment to this starting composition.

The application discloses a self-forming A-type molecular sieve foam material taking attapulgite as raw material and a preparation method and application thereof, and belongs to the field of green synthesis of molecular sieve foam materials. The steps are as follows: 1) grinding and sieving attapulgite to obtain attapulgite powder, and then calcining the attapulgite powder at 950-1000 DEG C for 2-4 hours to prepare activated attapulgite powder as a solid-phase raw material; 2) mixing the solid-phase raw material with an alkaline activator according to a mass ratio of 0.82-1.13:1, fully stirring and uniformly mixing, adding a seed crystal inducer, then adding a foaming agent, uniformly stirring, pouring into a mold, sealing, crystallizing, and obtaining the self-forming A-type molecular sieve foam material. The application only uses natural mineral attapulgite, does not add any chemical reagent as a silicon-aluminum source, obtains the self-forming A-type molecular sieve foam without a binder, and can effectively avoid problems such as pore blockage, dilution of effective molecular sieve sites and limitation of guest molecule transmission when used as an adsorbent.

The invention discloses a C3H8-SCR (selective catalytic reduction) catalyst as well as a preparation method and application thereof. The C3H8-SCR catalyst is a Cu-LTA silicon aluminum molecular sieve. The preparation method of the C3H8-SCR catalyst comprises the following steps: adding an acidity regulator into a copper salt solution until the copper salt solution is weak acid, then immersing an LTA silicon-aluminum molecular sieve, drying, and roasting under inert shielding gas to obtain the C3H8-SCR catalyst. The C3H8-SCR catalyst provided by the invention can be used for inhibiting propane from being directly oxidized by oxygen in a catalytic denitration reaction, reducing by-products, widening a temperature window of the denitration reaction, and ensuring higher denitration conversion rate and selectivity when the reaction is carried out at a wider reaction temperature.

This invention discloses a kinetically controlled method for preparing hierarchical porous molecular sieves, belonging to the field of catalyst preparation technology. It employs a two-step crystallization method: first, nucleation occurs at low and ultra-low H2O / SiO2 molar ratios; then, after the low-temperature phase, water is added, followed by rapid growth at high temperature and high H2O / SiO2 molar ratios. The solid-phase and liquid-phase crystallization mechanisms in the synthesis system work in succession to prepare hierarchical molecular sieves. This invention, without adding any mesoporous pore-forming agents, only modulates the crystallization temperature and the H2O / SiO2 molar ratio of the synthesis system to kinetically control the crystallization mechanism, resulting in molecular sieves with higher catalytic performance than those obtained using traditional methods. Furthermore, it overcomes the drawbacks of traditional hierarchical porous molecular sieve preparation processes, such as high cost, high calcination energy consumption, poor mesopore connectivity, and severe contamination from pore-forming agents.

The present application relates to the technical field of molecular sieve materials, and in particular to a method for synthesizing zeolite molecular sieves using economical raw materials; the method comprises: mixing high-silicon waste liquid and low-alumina concentration waste liquid, and performing a hydrothermal reaction to obtain a gel; solid-liquid separation of the gel to obtain a gel filter cake; adding a regulator to the gel filter cake, stirring the mixture, and then adding a seed crystal directing agent to perform a crystallization reaction, and performing separation, washing and drying to obtain a zeolite molecular sieve; wherein the volume ratio of the high-silicon waste liquid to the low-alumina concentration waste liquid is 1 to 3:1; the silicon oxide concentration of the high-silicon waste liquid is greater than 1 g / L, and the aluminum oxide concentration of the low-alumina concentration waste liquid is 5 g / L to 30 g / L; the method realizes the deep utilization of silicon in the high-silicon waste liquid and aluminum oxide in the low-alumina waste liquid, thereby significantly reducing the circulation amount of silicon and aluminum oxide in the alumina production process, thereby reducing the production cost of zeolite.

This invention provides a method for preparing a sound-absorbing composite material, comprising: Step 1: cleaning a support layer to remove surface contaminants; Step 2: forming a molecular sieve seed layer or a molecular sieve transition layer on the surface of the cleaned support layer, or sequentially forming a molecular sieve seed layer and a molecular sieve transition layer; Step 3: placing the product obtained in Step 2 in the growth solution of a third molecular sieve, followed by crystallization, drying, and calcination (with or without calcination) to form a molecular sieve outer layer. Compared with the prior art, the method for preparing the sound-absorbing composite material provided by this invention does not add a binder, but instead directly deposits a film on the inner wall of the rear cavity material of the loudspeaker, i.e., the support layer, through in-situ molding. The bond between the molecular sieve outer layer and the support layer is stronger, and the performance of the molecular sieve can be more fully and effectively utilized.

The invention discloses a method for converting quartz and mica impurities in sandy kaolin and synthesizing 4A zeolite, which comprises the following steps: uniformly mixing the sandy kaolin, sodium carbonate and aluminum hydroxide, wrapping with carbon paper, and heating in an ultrafast high-temperature furnace at 1100-1400 DEG C for 20 seconds to obtain a precursor; grinding the precursor into fine powder, and adding a proper amount of 0.01 mol / L NaOH solution to obtain a colloidal product; stirring the colloidal product at 80 DEG C for 4 hours, transferring the colloidal product to a reaction kettle, putting the reaction kettle into a drying oven, and performing hydrothermal treatment at 80-100 DEG C for 5-10 hours to obtain a crystallized product; and centrifuging the crystallized product at 5000 revolutions per minute for 1 minute, washing with distilled water for 3-4 times, and drying at 110 DEG C for 24 hours to obtain the 4A zeolite. According to the present invention, the precursor is rapidly generated under the action of sodium carbonate mainly for the sandy kaolin with characteristics of high quartz and mica impurity content, and the 4A zeolite with high purity can be synthesized after the hydrothermal treatment, such that the reaction energy consumption is reduced, the NaOH consumption is substantially reduced, and the green 4A zeolite synthesis method is superior to the traditional high temperature calcination method and the alkali fusion method in the green 4A zeolite synthesis aspect.

The invention provides an NH3-SCR catalyst and a preparation method and application thereof, the NH3-SCR catalyst comprises an LTA molecular sieve and active components loaded on the LTA molecular sieve, and the active components comprise Cu and rare earth metal elements. According to the invention, the LTA molecular sieve and the double active components composed of Cu and rare earth metal elements have a synergistic effect, so that the catalyst shows efficient NH3-SCR catalytic activity and excellent high-temperature hydrothermal stability, and when the catalyst is applied to an NH3-SCR reaction, 90% of NOx conversion rate can be maintained at 230-550 DEG C, and 90% of N2 selectivity can be maintained at the same time. The catalyst is used in the field of diesel vehicle tail gas denitration, can realize high-efficiency treatment of tail gas NOx, and accords with corresponding emission standard limits.

The present invention relates to the use of a C3-C6 alkene compound containing only one double bond in combination with at least one molecular sieve to limit or prevent the isomerization of trans-1-chloro-3,3,3-trifluoropropene to cis-1-chloro-3,3,3-trifluoropropene and / or to limit or prevent the decomposition of trans-1-chloro-3,3,3-trifluoropropene. The present invention also relates to methods for heating or cooling fluids or objects, methods for generating electricity, and heat transfer equipment. [Selection diagram] None

This invention discloses a tetrachloroaluminate-modified type A molecular sieve, its preparation method, and its application. The invention uses fly ash cenospheres as the main raw material to prepare a type A molecular sieve. Through modification with a mixture of fly ash and tetrachloroaluminate, it exhibits excellent adsorption performance for cobalt, cesium, and strontium ions. The type A molecular sieve prepared in this application has a good synergistic effect with tetrachloroaluminate, effectively solving the problems of complex processes, high costs, and poor adhesion of existing molecular sieve adsorbent preparation methods in the market. 137 Cs, 60 Co, 90 This method addresses the problem of low adsorption rates of major hazardous nuclides in radioactive wastewater such as Sr, and can be used to adsorb radionuclides in nuclear wastewater.

This invention belongs to the field of solid waste resource utilization and environmental protection technology, specifically relating to a type A zeolite adsorbent material based on ionic rare earth tailings and its preparation method. The invention involves sieving ionic rare earth tailings to obtain fine-grained particles rich in clay components, followed by heat treatment and alkaline solution crystallization to obtain type A zeolite. Then, thiol groups are grafted onto the zeolite surface using a silane coupling agent. Finally, an olefin compound containing terminal tert-butyl groups, phenolic hydroxyl groups, amino groups, Schiff bases, and a heptyl ring with a stereochemical structure is grafted onto the zeolite surface using a Michael addition reaction between thiol groups and double bonds. The phenolic hydroxyl, amino, and tert-butyl groups on the material surface form a good hydrophilic-hydrophobic structure, effectively improving the surface activity of the zeolite material, promoting the approach of heavy metal ions to the zeolite surface, and thus enhancing the adsorption effect of heavy metal ions.

The invention discloses a 4A zeolite electrocatalyst loaded with transition metal, the 4A zeolite electrocatalyst is loaded with 20-80% of transition metal, and the transition metal is Cu or Ni. The preparation method comprises the following steps: mixing 3 parts of Cu (NO3) 2.3 H2O or 3 parts of Ni (NO3) 2.6 H2O with 5 parts of protonated 4A zeolite, adding into 10mL of distilled water, mixing and stirring for 2 hours, pouring into a polytetrafluoroethylene liner and a stainless steel autoclave, carrying out hydrothermal reaction for 4 hours at 120 DEG C, pouring the solution into a centrifugal tube after the reaction is completed, centrifuging twice with distilled water, filtering, and drying at 90 DEG C, thereby obtaining the protonated 4A zeolite composite material. The 4A zeolite catalyst material loaded with the transition metal is obtained. The electrocatalyst disclosed by the invention is high in catalytic activity, relatively low in overpotential, high in stability and relatively high in energy conversion efficiency. The preparation method provided by the invention has the advantages of simple and easily available reaction raw materials, low price, mild synthesis conditions, simple process, low requirements on equipment, and realization of large-scale mass production, and the obtained catalyst material has a larger specific surface area and more active sites.

The invention provides a method for recovering nepheline in lithium feldspar tailings and a molecular sieve preparation method and equipment, and relates to the field of tailings recovery. The method for recovering nepheline in the lithium feldspar tailings comprises the following steps: S11, grinding, screening and calcining the lithium feldspar tailings in sequence; and S12, slurrying the calcined material, dispersing the material through an ultrasonic separation system, then adding a flocculating agent, adding the mixed slurry into a flexible recovery system, adding a flotation reagent, agglomerating a hydrophilic material, and settling and separating a hydrophobic material. According to the method for recycling the nepheline in the lithium feldspar tailings and the molecular sieve preparation method, the nepheline in the lithium feldspar tailings is recycled through a soft natural stripping process, the extraction rate of the nepheline is increased, then the nepheline is further purified and treated, the nepheline forms molecular sieve crystal mush, and molecular sieve particles are obtained through the following steps of roasting and curing and the like. Therefore, full utilization of the lithium tailings is realized, and waste utilization is realized.

The invention relates to a preparation method of a high-potassium 3A molecular sieve. The method comprises the following steps: obtaining a 4A molecular sieve filter cake; sequentially carrying out first washing and pulping on the 4A molecular sieve filter cake to obtain first slurry; carrying out continuous leaching on the slurry by using a first potassium ion exchange solution in a plane washing manner to carry out first ion exchange so as to obtain a leaching filter cake; mixing the leaching filter cake with a second potassium ion exchange liquid to obtain a mixed material; stirring the mixed material at a set temperature for second ion exchange to obtain a second slurry; the second slurry is sequentially subjected to separation, second washing and drying, and high-potassium 3A molecular sieve raw powder is obtained. In the first ion exchange stage, primary exchange of potassium ions and sodium ions is realized through continuous leaching; in the second ion exchange stage, the potassium ions are further pushed to be diffused to deep pore channels of the molecular sieve through dynamic stirring, and deep replacement of the residual sodium ions is completed. According to the staged exchange mode, not only is the exchange thoroughness ensured, but also the process efficiency is improved.

The invention relates to the technical field of molecular sieve material preparation, and discloses a synthesis method for preparing a NaX / A eutectic molecular sieve by utilizing crystallization mother liquor circulation, which comprises the following steps: step 1, uniformly mixing lithium slag and 48% sodium hydroxide solution, calcining at 330-450 DEG C, and naturally cooling to room temperature to obtain activated alkali molten slag; step 2, mixing the activated alkali molten slag with pure water according to a mass ratio of 1: 5-1: 10, putting the mixture into a hydrothermal reaction kettle, carrying out hydrothermal crystallization reaction at 90-120 DEG C, finally filtering to obtain crystallization mother liquor, washing and drying to obtain a NaX / A eutectic molecular sieve; and step 3, adding CaO or Ca (OH) 2 into the crystallization mother liquor separated in the step 2, reacting in a water bath at a certain temperature, concentrating after removing impurities, and returning to the step 1 for recycling. The synthesis method disclosed by the invention is simple in process, mild in condition, low in raw material cost and zero in emission, and meets the requirement of green production.

The application discloses a phosphogypsum reverse flotation tailing-based lanthanum modified zeolite material and a preparation method and application thereof. The preparation method of the phosphogypsum reverse flotation tailing-based lanthanum modified zeolite material comprises the following steps: uniformly mixing phosphogypsum reverse flotation tailings and NaOH particles according to a mass ratio of 1:1.0-1.4, performing alkali fusion activation treatment under the condition of 550-650 DEG C, and obtaining alkali fusion clinker; performing ball milling and sieving on the alkali fusion clinker after cooling in air, obtaining clinker powder, mixing the clinker powder and water according to a solid-liquid ratio of 5-10 mL / g, adding LaCl3 solution and uniformly mixing, performing hydrothermal crystallization treatment under the condition of 90-120 DEG C, and obtaining a crystallization product; filtering the crystallization product, washing until the pH of a washing-out liquid is 7-8, and drying. The application utilizes the phosphogypsum reverse flotation tailings as raw materials, realizes the resource utilization of industrial waste, and reduces the stockpiling of the tailings and the potential pollution to the environment.

The present invention provides: a negative thermal expansion material which is reduced in cost and density; and a composite material. A negative thermal expansion material according to one embodiment of the present invention has a negative thermal expansion coefficient, while containing at least one substance which is selected from the group consisting of MER type zeolite, GIS type zeolite, LTA type zeolite and FAU type zeolite. A composite material according to one embodiment of the present invention contains the above-described negative thermal expansion material and a material which has a positive thermal expansion coefficient.

The present application relates to a molecular sieve composition, a preparation method thereof and application thereof. The molecular sieve composition of the present application comprises a mosaic molecular sieve of a TON structure molecular sieve and a 5A type molecular sieve. The molecular sieve composition of the present application has a dual function of adsorption and hydroisomerization.

The application discloses a modified 5A molecular sieve, and a preparation method thereof. The modified 5A molecular sieve is characterized in that the modified 5A molecular sieve is composed of 5A molecular sieve and a silicon-containing compound, wherein the mass ratio of the 5A molecular sieve to the silicon-containing compound is 1:0.005-0.25, and the average crystal grain size of the modified 5A molecular sieve is not more than 1 mu m. The preparation method of the modified 5A molecular sieve comprises the preparation of 5A molecular sieve and silanization treatment.

The invention provides a method of producing zeolite from an acid-refractory mineral composition, the method comprising: (a) treating an acid-refractory mineral composition comprising aluminosilicate with an alkaline solution to dissolve silicon from the aluminosilicate into the alkaline solution, thereby producing an alkaline silicate solution and an aluminium-bearing mineral residue; (b) separating the alkaline silicate solution from the aluminium-bearing mineral residue; (c) contacting the aluminium-bearing mineral residue with an acid solution to dissolve aluminium from the aluminium-bearing mineral residue into the acid solution, thereby producing an aluminium salt solution and an aluminium-lean solid residue; (d) separating the aluminium salt solution from the aluminium-lean solid residue; (e) combining at least a portion of the alkaline silicate solution and at least a portion of the aluminium salt solution to form a zeolite precursor solution; and (f) precipitating a zeolite from the zeolite precursor solution.

This invention relates to the field of molecular sieve catalytic materials preparation, and discloses a method for preparing molecular sieves containing rare earth elements. The method includes: under hot-pressing conditions, subjecting a molecular sieve containing ammonium ions to an ion exchange reaction with rare earth element ions in an ion exchange reaction solution to obtain a molecular sieve containing rare earth elements; wherein the hot-pressing conditions include: a temperature of 160-190℃ and a pressure of (P+0.1)~(P+2) MPa, where P represents the saturated vapor pressure of water at the ion exchange temperature, in MPa. The method of this invention enables efficient and continuous exchange production, obtaining molecular sieves containing rare earth elements without the need for high-temperature calcination in a calcination converter.

The invention relates to a method for preparing a modified zeolite molecular sieve and co-producing a 3A molecular sieve and application, and belongs to the technical field of molecular sieves. The method comprises the following steps: mixing a K-SAPO-34 molecular sieve serving as a seed crystal with a silicon source, an aluminum source, a potassium source and a phosphorus source, and carrying out hydrothermal crystallization reaction; carrying out ammonium exchange on a product after hydrothermal crystallization; and carrying out sodium exchange on the product after ammonium exchange. The modified zeolite molecular sieve prepared by the method is green and environment-friendly in preparation process, is beneficial to large-scale production, still has relatively high potassium ion adsorption capacity after being formed, and has a good application effect in the field of potassium extraction. Meanwhile, the 3A molecular sieve is co-produced, so that exchange liquid resources can be reasonably utilized, and the overall production cost is further reduced.

The invention relates to the field of fine chemicals, and in particular to a method for preparing sodium difluorophosphate. The method adopts sodium carbonate, difluorophosphoric acid, a solvent, and a desiccant, and carries out reaction, filtration, and purification to obtain the sodium difluorophosphate. In the method, the difluorophosphoric acid is firstly purified by adsorption with a silsesquioxane adsorption resin, and the purity after purification is as high as 99.5%. The desiccant uses a NaA molecular sieve, and the NaA molecular sieve is prepared by adopting SiO2, Al2O3, sodium hydroxide, deionization, aging, microwave nucleation, and crystallization. The NaA molecular sieve prepared by the method has good performance and a large static water absorption capacity. The method for preparing the sodium difluorophosphate of the invention has a simple process, low equipment investment, low reaction temperature, easy separation, and high product purity.

The application discloses modified A-type molecular sieves, a preparation method and application thereof. The A-type molecular sieves are prepared by taking fly ash floating beads as a main raw material, alkali active sites are generated by ion exchange between the A-type molecular sieves and ammonium fluoride, the alkali active sites on the surface of the molecular sieves are reacted with ammonia water, a coordination reaction between lone pair electrons and heavy metal ions is generated, and the purpose of adsorption is achieved.

The invention provides a preparation method and application of a natural mineral-based molecular sieve optimized based on a response surface method.The molecular sieve is prepared from natural minerals as a base material through acid treatment, alkali fusion and hydrothermal synthesis, high crystallinity and high adsorption capacity serve as targets, the particle size of mineral powder is systematically optimized through a response surface method, and the particle size of the mineral powder is reduced. The molecular sieve is prepared according to key parameters such as pH, mass ratio, temperature and time of acid treatment, mass ratio, temperature, time and silica-alumina ratio of alkali melting, and hydrothermal synthesis temperature and time; the prepared molecular sieve can be applied to treatment of industrial wastewater and can be regenerated and recycled after being used. The cost is low, crystallization can be realized at low temperature, and operation is simple and safe. The molecular sieve prepared by the method has the advantages of high crystallinity, high specific surface area and high adsorption capacity, and can be used for wastewater treatment in the industries of coal chemical industry, petrochemical industry, smelting, breeding and the like.