44results about "Pentasil aluminosilicate zeolite" patented technology

The present application relates to the technical field of ZSM-5 molecular sieve preparation, and provides a high-crystallinity aluminum-rich ZSM-5 molecular sieve, a preparation method and application thereof.The preparation method of the high-crystallinity aluminum-rich ZSM-5 molecular sieve provided by the present application realizes the skeleton composition control of the ZSM-5 molecular sieve by adding a second aluminum source and then performing secondary crystallization, solves the technical bottleneck that it is difficult to directly synthesize the high-crystallinity aluminum-rich ZSM-5, breaks through the lower limit of the Si / Al ratio phase region of the artificial in-situ synthesis of the molecular sieve, effectively controls the crystal parameter and improves the production efficiency, realizes the precise construction of the high-crystallinity aluminum-rich ZSM-5 molecular sieve, and thus enhances the micropore crystallinity of the molecular sieve, optimizes the acid distribution, greatly enriches the metastable surface active acid center distribution of the molecular sieve, and has good aromatic hydrocarbon conversion performance.

This invention discloses a method for preparing ZSM-5 molecular sieves using a microwave-assisted method with desilication solution, comprising the following steps: First, pretreatment of the desilication solution: the desilication solution is mixed with an oxyacid to adjust the pH to 9-11.5, a template agent is added and mixed evenly to obtain an initial gel; Second, preparation of the ZSM-5 molecular sieve: the initial gel obtained in the first step is placed in a microwave synthesizer for aging with high-speed stirring; the aged solution undergoes a crystallization reaction, followed by filtration, washing, drying, and high-temperature calcination to obtain the ZSM-5 molecular sieve. This invention uses desilication solution as a raw material to prepare ZSM-5 molecular sieves, saving material costs and providing a new approach for the high-value utilization of desilication solution. Furthermore, by utilizing microwave-assisted synthesis on the basis of the traditional hydrothermal method, the time cost is effectively shortened.

The present application relates to waste catalyst treatment field, disclose a kind of production method and nano molecular sieve using waste zeolite molecular sieve catalyst as raw material to prepare nano zeolite molecular sieve, the method comprises: (1) the waste zeolite molecular sieve catalyst of micron grade crystal grain size is calcined and impurity is removed;(2) subsequently it is placed into high-energy nanoscale ball mill and is ball milled, and the nanoscale amorphous fragment powder with crystal structure unit is obtained;(3) after the powder is mixed with water, alkali, structure directing agent, surfactant, and then hydrothermal crystallization is carried out by microwave irradiation;The frequency of microwave irradiation is above 433.92MHz, and the mass ratio of ball milling medium to raw material is above 3.The method of the present application can be used to synthesize nano molecular sieve using micron-sized raw materials.

The application provides a preparation method of a composite molecular sieve and application of the composite molecular sieve in heavy oil cracking, and the preparation method comprises the following steps: dissolving an aluminum source, a silicon source and a structure directing agent in water, and then performing crystallization treatment to obtain a ZSM-5 crystal seed solution; etching Y type molecular sieve in water by using an alkaline substance to form a hollow structure, and then mixing the hollow Y type molecular sieve with acidic silica sol to obtain a solution containing the hollow Y type molecular sieve; mixing the ZSM-5 crystal seed solution and the solution containing the hollow Y type molecular sieve, and then performing temperature crystallization, and then separating a crystallization product, and then performing washing, drying and calcination to obtain a ZSM-5 / Y composite molecular sieve, and then performing ion exchange reaction, and then performing calcination to obtain a H type ZSM-5 / Y composite molecular sieve product. The composite molecular sieve synthesized by the application has the advantages of high activity, good selectivity and the like when the composite molecular sieve is prepared into a catalyst, high liquefied gas and propylene yield can be obtained, and the composite molecular sieve is particularly suitable for the field of petrochemical catalytic cracking.

This invention discloses a method for preparing zeolite molecular sieves with precisely adjustable particle size, comprising the following steps: (1) adding aluminum source and other raw materials to deionized water and stirring evenly at room temperature; (2) adding silicon source, stirring at room temperature, and then adding template agent to obtain precursor slurry; (3) adding zeolite molecular sieve, the amount of zeolite molecular sieve being 1-15 mg / g of precursor slurry, transferring the precursor slurry to a high-pressure reactor, fixing it on a homogeneous reactor, heating to 0-150℃, maintaining for 1-200 h, and then heating to 160-230℃ for 3 hours to crystallize for 6-96 h; (4) obtaining zeolite molecular sieve after centrifugal washing, drying, and calcination. The innovation of the preparation method of this invention lies in the first use of a two-stage synthesis method, which can gradually reduce the particle size of the zeolite molecular sieve product while increasing the yield of zeolite molecular sieves. This method successfully synthesized SAPO-34 zeolite molecular sieve with a particle size deviation of less than 0.4 μm and ZSM-5 zeolite molecular sieve with a particle size deviation of less than 0.2 μm.

The present invention relates to an improved porous solid catalyst (C) adapted for the conversion of methanol and derivatives thereof into low-molecular weight hydrocarbons, based on a zeolite, such as ZSM-5, and on inorganic oxide, such as ceria, in a preferable weight ratio of zeolite:inorganic oxide between 1:1 and 1:5. It further relates to a conversion process and to a system using such a catalyst.

The application discloses a short-time crystallization preparation method of high-crystallinity low-silicon-aluminum ratio H-ZSM-5 molecular sieve and application thereof, and belongs to the field of molecular sieve synthesis. The preparation method comprises the following steps: S1, mixing a silicon source with water to obtain solution A; mixing an aluminum source with water to obtain solution B; mixing an organic amine with water to obtain solution C; S2, adding solution B into solution A, then adding solution C, finally adding seeds, stirring, crystallizing, separating, ion exchanging, drying and roasting to obtain the high-crystallinity low-silicon-aluminum ratio HZSM-5 molecular sieve. The crystallization time is 2-4 h. The HZSM-5 molecular sieve has high crystallinity, the silicon-aluminum ratio is 30-55, the raw material price is low, the amount of organic template agent is small, the synthesis time is very short, the yield is high, the product morphology is hexagonal plate, the particle size is about 2-4 µm, and the HZSM-5 molecular sieve has a good application prospect in the fields of petroleum catalytic cracking and fine chemical industry.

The present application relates to a kind of high selectivity molecular sieve based on high-silicon low-calcium fly ash preparation and its preparation method and application, belong to molecular sieve preparation technical field.To solve the problem that molecular sieve crystallization process and high-silicon low-calcium fly ash raw material characteristics do not match, the present application provides the preparation method of high selectivity molecular sieve based on high-silicon low-calcium fly ash preparation, steps include targeted removal Fe2O3 Impurity, silicon-aluminum is activated and dissolved to obtain the silicate gel of controllable water content, using seed and mechanical force coupling direction solid phase crystallization and forming calcination obtain SiO2-Al2O3 Type molecular sieve.The present application improves the purity of molecular sieve crystal to 90~98%, the deviation of pore size distribution is reduced to below 5%, greatly improves the regularity and stability of molecular sieve crystal structure, also improves its adsorption capacity to NH4 + , CO2 And the separation coefficient of NH4 + And other cations, has wide application prospect in wastewater denitrification and carbon capture field.

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 provides a template agent and a preparation method thereof, and a macroporous ZSM-5 molecular sieve and a synthesis method thereof. The preparation method of the template agent comprises the following steps: mixing maleic anhydride, an initiator and a first organic solvent to obtain a reaction solution A, and then introducing alpha-olefin to carry out copolymerization reaction with the reaction solution A to obtain a liquid-solid mixture B; carrying out liquid-solid separation on the liquid-solid mixture B, washing an obtained solid C with a second organic solvent, and drying to obtain a product D; and carrying out ammoniation treatment on the product D to obtain the template agent E. The template agent containing the monoolefine-maleic anhydride polymer is introduced into the ZSM-5 molecular sieve through a secondary synthesis method, inorganic acid or organic acid does not need to be added in the synthesis process, the molecular sieve is easier to form, the ratio of macropores in the ZSM-5 molecular sieve is increased, and the ZSM-5 molecular sieve has high crystallinity.

The application relates to a preparation method of ZSM-5 nanosheet zeolite and belongs to the technical field of catalyst preparation. The preparation method is used for synthesizing b-axis directional growth ZSM-5 molecular sieve under a seed guiding liquid in an acid medium and a fluorine-free system. The method comprises the following steps: mixing an aluminum source, inorganic acid, inorganic alkali, a silicon source and deionized water, fully stirring to form a gel, adding a small amount of seed guiding liquid, and adjusting the pH of the synthesis gel to be between 4 and 6 by controlling the adding amount of the inorganic acid. The b-axis directional growth ZSM-5 nanosheet is obtained by crystallization treatment at a certain temperature. The method is an inorganic system synthesis in a fluorine-free system, the silicon aluminum ratio is adjustable between 30 and 120, the system is green and environmentally friendly, the cost is low, the problems of high cost, limited silicon aluminum ratio and serious environmental pollution in the fluorine-containing system and the addition of organic growth agents for synthesizing directional growth nanosheets are solved.

The application discloses a Beta / ZSM-5 symbiotic zeolite molecular sieve, a hydrocracking catalyst and a preparation method and application thereof. The Beta / ZSM-5 symbiotic zeolite molecular sieve has the topological structures of BEA and MFI, wherein the particle size of the particle with the topological structure of BEA is 50-500 nm, and the particle size of the particle with the topological structure of MFI is 3-6 mu m; preferably, the molar ratio of the silicon-aluminum oxide molecular substance of the Beta / ZSM-5 symbiotic zeolite molecular sieve is 25-300, preferably 50-200. The hydrocracking catalyst is applied to a catalytic diesel hydrocracking reaction, and the yield of light aromatic hydrocarbons and benzene in the reaction product can be effectively improved.

The present invention relates to the technical field of molecular sieve preparation. Provided are a binderless ZSM-5 molecular sieve catalyst having a silicon-rich surface, and a preparation method therefor and the use thereof. The overall SiO2 / Al2O3 ratio of the ZSM-5 molecular sieve catalyst is 50-500, and the surface-layer SiO2 / Al2O3 ratio of the ZSM-5 molecular sieve catalyst is 5-50% higher than the overall SiO2 / Al2O3 ratio; and the content of a surface acid site having an acid strength H0 of greater than or equal to +2.27 in the ZSM-5 molecular sieve is less than or equal to 0.04 mmol / g. The binderless ZSM-5 molecular sieve catalyst having a silicon-rich surface provided by the present invention does not contain an inert binder, has an extremely weak surface acidity, and can improve the catalytic effect and reduce the production of by-products. In addition, the preparation method provided by the present invention has a simple process and is suitable for industrial production.

The application provides a preparation method of two-dimensional ZSM-5 molecular sieve, comprising the following steps: A) mixing coal gasification fine slag with an activating agent, roasting to obtain a roasting mixture; B) mixing the roasting mixture, a silicon source, a template agent, water and lye to obtain a suspension, aging the suspension and then crystallizing to obtain a crystallization product; and C) calcining the crystallization product to obtain two-dimensional ZSM-5 molecular sieve. In the preparation process of the two-dimensional ZSM-5 molecular sieve, the residual carbon in the coal gasification fine slag is excited to be active by the activating agent, then without any post-treatment process, the template agent, the silicon source, the water and the lye are directly added, and the two-dimensional sheet ZSM-5 molecular sieve is directly synthesized through hydrothermal crystallization, and the method has the advantages of mild synthesis condition, simple steps and high reproducibility.

The application relates to the field of silicon-aluminum molecular sieve preparation, and discloses a ZSM-5 molecular sieve and a preparation method and application thereof. The molecular sieve has a cage-shaped structure formed by stacking sheet-shaped primary crystal grains. The ZSM-5 molecular sieve provided by the application has high catalytic activity.

The present invention provides: an inorganic porous carrier, which can increase yield, etc., in the preparation of nucleic acids, has pore distribution in which a pore diameter (mode diameter) is 0.04 µm or more, and comprises a linker represented by formula (1) [wherein, a bond marked with * represents a bond to an oxygen atom of a silanol group in an inorganic porous substance. R1 and R2 represent each independently an alkyl group containing 3 to 10 carbon atoms, or a phenyl group. L represents a single bond; an alkylene group containing 1 to 20 carbon atoms; or an alkylene group containing 2 to 20 carbon atoms which contains -CH2-Q-CH2-group wherein any group Q selected from a group consisting of -O-, -NH-, -NH-CO-, and -NH-CO-NH- is inserted into at least one of -CH2-CH2- group constituting the alkylene group. A carbon atom of the methylene group bound to the group Q does not bond to another group Q at the same time.]; and a method for preparing nucleic acids using the same.

The objective is to provide at least one of the following: an MFI-type zeolite having excellent catalytic activity, as well as excellent durability and handling properties, and a method for producing the same. [Solution] An MFI-type zeolite having a molar ratio of silica to alumina of 40 to 150, an average primary crystal diameter of 0.1 μm to 5 μm, a standard deviation of volume particle size distribution of 15 μm or less, and an acid content of 0.50 mmol / g or more.

The application discloses a preparation method of nano-flower-like ZSM-5 nanosheet zeolite. The preparation method comprises the following steps: mixing an aluminum source solution and a silicon source to obtain a gel, and adjusting the pH of the gel to be 7-10; after aging of the obtained gel, the gel is mixed with a long carbon chain surfactant and a non-ionic surfactant, and then hydrothermal reaction is carried out after the mixing, so that crystals are precipitated; and the obtained crystals are dried and calcined to obtain the ZSM-5 nanosheet zeolite. The method is simple and low in cost. The synthesized product has a widely adjustable silicon-aluminum ratio, an ordered adjustable mesoporous structure, a mesopore size adjustable between 5-20 nm, and a nanosheet thickness reducible to about 10 nm, and meanwhile, the nanosheets are column-supported, and have excellent stability, so that the product has a better application prospect in the field of catalysis.

The application discloses a ZSM-5@Silicalite-1 core-shell molecular sieve and a preparation method and application thereof. The preparation method comprises the following steps: mixing an aluminum source, a silicon source I, a template agent, Silicalite-1 crystal seeds, water and alkali, crystallizing I, adding a silicon source II and water, crystallizing II in a closed container, drying, and obtaining the ZSM-5@Silicalite-1 core-shell molecular sieve; wherein the Silicalite-1 is a core, and the ZSM-5 is a shell. The mass ratio of the silicon source I / the silicon source II is fixed, the size of the Silicalite-1 crystal seeds and the adding amount are synchronously changed, and the ZSM-5@Silicalite-1 core-shell material with the same crystal size is obtained.

The present application aims to provide at least any one of a zeolite having an oxygen 10-membered ring structure, which can improve a para-xylene selectivity in the production of alcohol-modified xylene and can be adapted to an industrial process at a low cost, an alcohol-modification catalyst comprising the same, and a xylene production method using the same. A zeolite having an oxygen 10-membered ring structure, which comprises one or more elements selected from magnesium, calcium, titanium, boron, and phosphorus, and has a total pore volume of 0.21 cm 3 / g or less.

The application provides a carbon dot modified molecular sieve and a preparation method thereof, a food sample pretreatment extract and a preparation method and application thereof, and belongs to the technical field of food sample pretreatment. The ZSM-5 molecular sieve and the ferroferric oxide powder are dispersed in water to obtain a mixed dispersion liquid; the mixed dispersion liquid and a paramecium culture solution are mixed, and then static treatment and centrifugal separation are sequentially performed to obtain supernatant and a precipitate; finally, the precipitate is sequentially subjected to carbonization treatment, freeze-drying and magnetic separation to obtain the carbon dot modified molecular sieve. The carbon dot modified molecular sieve is mixed with a salt solution to obtain the food sample pretreatment extract. The food sample pretreatment extract of the application can adsorb biological macromolecules such as proteins and fats through the micropores of the molecular sieve, and the polypeptides in the carbon dots can form small cavities on the surface of the molecular sieve by winding each other, so that the small cavities can adsorb additives such as pigments and essences.

The application discloses a ZSM-5 molecular sieve production process and stirring equipment thereof and belongs to the technical field of ZSM-5 molecular sieve production, and comprises the following steps: a synthesis reaction, filtration and washing, flash drying, calcination and crushing. After being heated to 100-200 DEG C, the frequency conversion of stirring is reduced by 20-50%, which helps to reduce unnecessary energy consumption while ensuring sufficient mixing, and avoids material breakage or structure damage caused by excessive stirring, thus helping to improve reaction efficiency and product quality; by adjusting a silicon source and adding 0.1%-3% of a halide, crystal growth is accelerated and a crystallization reaction is shortened; by controlling the water flow of water washing, efficient impurity removal efficiency is ensured, the process can not only effectively remove unreacted raw materials and other impurities, but also can reduce the content of Na+ to below 2000ppm, improve the purity of the final product and significantly improve the physical and chemical properties of the final product.

The objective is to provide at least one of the following: an MFI-type zeolite having excellent catalytic activity, as well as excellent durability and handling properties, and a method for producing the same. [Solution] An MFI-type zeolite having a molar ratio of silica to alumina of 80 to 250, an average primary crystal diameter of 0.1 μm to 5 μm, a standard deviation in the volume particle size distribution of 15 μm or less, and an acid content of 0.20 mmol / g or more.

This invention belongs to the field of solid waste resource utilization technology. It discloses a ZSM-5 molecular sieve prepared using secondary aluminum ash and fly ash, its preparation method, and its applications. The preparation method involves mixing fly ash with sodium carbonate, calcining to activate it, and then acid leaching to extract the silicon-aluminum source. Simultaneously, secondary aluminum ash reacts with calcium oxide in an aqueous phase to obtain a supplementary aluminum source. The two extracts are mixed in a specific ratio, and a template agent, alkali additive, and seed crystals are added. After grinding, a homogeneous mixture is formed, and the mixture is crystallized at a suitable temperature for a certain time. Finally, through cooling, separation, washing, drying, and calcination steps, nano-ZSM-5 molecular sieves are obtained. This method achieves synergistic high-value utilization of two solid wastes. The prepared ZSM-5 molecular sieve has the characteristics of fine grains, adjustable silicon-aluminum ratio, and hierarchical porous structure, and can be used as a denitrification catalyst or adsorbent in the fields of waste gas treatment and gas separation.

The application relates to a method for synthesizing a multi-level hole ZSM-5 molecular sieve, which directly obtains the multi-level hole ZSM-5 molecular sieve through hydrothermal crystallization of amorphous high-silicon mineral soil raw materials and activated low-silicon mineral soil raw materials and seed crystals activated by hot alkali. In the method, the silicate and aluminate in the mineral provide all the silicon source and aluminum source for synthesis, without adding external silicon source or aluminum source, and without adding expensive organic amine template agents, so that the method belongs to an environment-friendly low-cost molecular sieve green synthesis method, and the prepared multi-level hole ZSM-5 has high crystallinity and rich mesoporous structures and can be applied to petroleum chemical catalysts.

The present disclosure provides an epoxy coating and a preparation method thereof, the preparation method comprising the following steps: Step 1, preparation of nano-container mesoporous ZSM-5; Step 2, assembly of pH stimulus-responsive intelligent nano-container, mainly including vacuum adsorption of 8-HQ, electrostatic adsorption of PEI and PSS, ion exchange of Ce 3+ and electrostatic adsorption of PSS; Step 3, preparation of an epoxy coating on an aluminum alloy surface. The mesoporous ZSM-5 of the present disclosure itself has a pH stimulus-responsive performance, and after the assembly of the intelligent nano-container, the release amount of the corrosion inhibitor and the fluorescent probe under neutral conditions can be extremely low, the release amount of Ce 3+ is about 1.54E-2 mmol, and the release amount of 8-HQ is about 1.58E-2 mmol, which changes the major defect that ZSM-5 releases a large amount of corrosion inhibitor under neutral conditions, and the prepared epoxy coating has the dual functions of self-warning and self-repair.

The application belongs to the technical field of petroleum processing and petrochemical catalysts, and particularly relates to a phosphorus-doped hierarchical pore ZSM-5 zeolite and a preparation method and application thereof. The phosphorus-doped hierarchical pore ZSM-5 zeolite is prepared by a one-step hydrothermal synthesis method. The phosphorus element enters the zeolite framework in a stable four-coordinated form, forms a strong chemical bond with silicon and aluminum atoms, and simultaneously realizes the framework-level coordinated doping of the phosphorus element and the precise construction of micro-mesopore-macropore hierarchical channels, successfully solving the contradiction between the insufficient hydrothermal stability of the hierarchical pore zeolite and the channel blockage caused by phosphorus modification. The prepared zeolite has a crystallinity retention rate of > 85% after hydrothermal treatment at 800 DEG C, has excellent physical structure, chemical stability and outstanding catalytic performance, provides an ideal material solution for developing a new generation of long-life and high-efficiency petrochemical catalysts (especially for processes such as olefin cracking and MTO), and has great scientific value and broad industrial application prospect.

The application discloses a method for removing trace water from carbon dioxide, which comprises the following steps: firstly, mixing tetrapropylammonium hydroxide and deionized water uniformly to obtain solution A; dissolving potassium aluminate in the solution A to obtain solution B; adding tetraethyl orthosilicate into the solution B drop by drop, stirring and mixing; transferring the solution C into a hydrothermal kettle to react for at least 2 hours; after the reaction is completed, taking out the reaction product, washing with water, centrifugal separation and drying; continuously heating to 550 DEG C, calcining for at least 2 hours to obtain K-ZSM-5; preparing an ethanol solution of potassium ethoxide, immersing the K-ZSM-5 in the ethanol solution of potassium ethoxide, removing ethanol from the immersed K-ZSM-5 under vacuum, and obtaining an adsorbent; filling the adsorbent into an adsorption column, passing carbon dioxide into the adsorption column, and removing water in the carbon dioxide by using a chemical adsorption method. The preparation method of the adsorbent is simple, the material is easy to obtain, the whole impurity removal stage does not need high temperature, the impurity removal method is simple, the efficiency is relatively high, and the water content can be reduced to below 20 ppb.