19 results about "Zeolite membranes" patented technology

A porous cylindrical support for use in supporting a zeolite membrane has a generally cylindrical inside surface having a central axis extending in the longitudinal direction and a generally cylindrical outside surface that surrounds the inside surface. A zeolite membrane is formed on the outside surface. A maximum value A and a minimum value B of a support thickness in a circumferential direction satisfy (A−B) / (A+B)≤0.3 in at least part of the support in the longitudinal direction, the support thickness being a radial distance between the inside surface and the outside surface. By reducing a variation in support thickness, it is possible to improve uniformity in the thickness of the zeolite membrane formed on the support.

The application provides a preparation method of a fluorine-free hydrophobic modified W-MEL or W-MFI zeolite molecular sieve membrane for oil-water separation, i.e. an in-situ crystallization method for preparing W-MEL and W-MFI type zeolite molecular sieve membranes. The method first pretreats a carrier with 3-aminopropyl triethoxysilane, then places the carrier in a reaction kettle, and performs high-temperature crystallization in a synthesis liquid to obtain W-MEL and W-MFI zeolite molecular sieve membranes with excellent performance. The research provides a simple synthesis method for novel W-MEL and W-MFI zeolite membrane materials, and innovatively proposes a fluorine-free hydrophobic modification strategy, so that the oil-water mixture can be effectively separated, and the method is applied to dye adsorption. The method provided by the application has strong operability, and has important industrial promotion and practical application value.

The application belongs to the technical field of chemistry and chemical industry, and particularly relates to a method for regenerating and utilizing waste stripping liquid of photoresist. The waste stripping liquid of photoresist is regenerated and utilized by the following steps: realizing waste liquid demulsification, viscosity reduction and impurity removal through specific modified magnetic nanoparticles, then carrying out pervaporation dehydration through a zeolite membrane covered with a zirconium-tannic acid-polyethyleneimine metal organic coordination network layer, and finally carrying out adsorption polishing and recombination, so that the waste stripping liquid of photoresist is regenerated and utilized, the water removal rate of the waste liquid is greater than 99.9%, and the recovery rate of effective components in the waste liquid is greater than 99.5%.

The utility model belongs to the technical field of carbon dioxide hydro-conversion, particularly relates to a membrane reactor for a reaction-separation coupling process, and aims to solve the problem of performance failure of the membrane reactor in a high-temperature environment in the background technology, the following scheme is provided: the membrane reactor comprises a reaction tube body, end covers are screwed on the outer walls of two ends of the reaction tube body, and the end covers are screwed on the outer walls of two ends of the reaction tube body; a product gas outlet is welded to one end of the outer wall of the bottom of the reaction tube body, a feed gas inlet is welded to the other end of the outer wall of the top of the reaction tube body, and a purge gas outlet is welded to the outer wall of one side of one end cover. The NaA molecular sieve membrane loaded by the ceramic hollow fiber carrier is adopted, a compact and defect-free zeolite membrane layer is formed through a multi-time in-situ growth process, the membrane can still keep a stable hydrophilic nano channel (the aperture is 0.4 nm) at the temperature of 300-400 DEG C and the high pressure of 4 MPa, water molecules are preferentially adsorbed and permeated, the thermodynamic equilibrium limitation is effectively broken, and compared with a traditional molecular sieve membrane, the membrane has the advantages that the membrane is simple in structure and convenient to use, and the cost is low. The thermal stability is obviously improved.

The invention relates to the technical field of metal anticorrosive coatings, in particular to a preparation process for eliminating performance difference of two sides of an aluminum alloy matrix MFI zeolite membrane, which comprises the following steps: preparing MFI zeolite membrane synthesis mother liquor from sodium hydroxide, deionized water, tetraethoxysilane and tetrapropylammonium hydroxide; carrying out surface treatment on the aluminum alloy matrix; the aluminum alloy matrix is placed in a reaction kettle containing mother liquor, and the aluminum alloy matrix does not make direct contact with the mother liquor initially; putting the reaction kettle into a drying oven for reaction; the reaction kettle is inverted, so that the surface of the aluminum alloy matrix is in uniform contact with the mother liquor and continuously reacts, and finally the MFI zeolite membrane with consistent properties on two sides is formed. The reaction kettle is heated until a uniform temperature field and a uniform fluid field are formed, and then the reaction kettle is inverted, so that the aluminum alloy is in uniform contact with the reaction liquid containing the primary crystal nucleus, the different-plane effect caused by the uneven temperature field, concentration field and convection in the reaction kettle in the in-situ hydrothermal synthesis process is effectively eliminated, and a foundation is laid for the in-situ hydrothermal synthesis process from laboratory research to large-scale industrial application.

A zeolite membrane structure (10) includes a support (20), a zeolite membrane (30), and a protective film (40). The zeolite membrane (30) is formed on a surface (23S) of the support (20). The protective film (40) is formed on a surface (30S) of the zeolite membrane (30). The protective film (40) is composed of organic-inorganic hybrid silica or carbon.

The application belongs to the field of fine chemical product preparation, and discloses a method for preparing gamma-valerolactone based on reaction-separation coupling. The method is realized based on a reaction-separation coupling system, and the reaction-separation coupling system comprises a first reactor, a membrane separation system, a second reactor and a rectification system. The specific steps are as follows: furfuryl alcohol is introduced into the first reactor filled with an acid catalyst at a fixed flow rate to complete hydrolysis to generate levulinic acid, the hydrolysis product is dehydrated through a NaA type zeolite membrane separation system, and then is introduced into the second reactor filled with a hydrogenation catalyst to complete a hydrogenation-cyclization reaction in the presence of isopropyl alcohol as a hydrogen donor; the product is separated through the rectification system to obtain high-purity gamma-valerolactone, and the separated water and unreacted raw materials are returned to the first reactor for recycling. The method realizes efficient circulation of materials and improves the preparation efficiency.

The application discloses a kind of green preparation methods of hydrophilic ZSM-5 zeolite membrane and its application, belong to inorganic membrane separation technical field.The application includes the following steps: S1, precoat ZSM-5 seed on the surface of porous carrier;S2, silicon source, aluminum source, alkali source, deionized water and isopropyl alcohol are mixed, and stirring is obtained even organic ammonium template-free synthesis liquid;S3, the porous carrier of precoat seed is placed in the synthesis liquid, and hydrothermal crystallization reaction is carried out;S4, after reaction, membrane body is taken out, and washed to neutral with deionized water, after drying, calcination treatment, obtain hydrophilic ZSM-5 zeolite membrane.The application avoids the high cost and environmental pollution problem caused by organic ammonium template from root, and the prepared zeolite membrane shows excellent separation performance in pervaporation dehydration of ethanol, isopropyl alcohol, acetone and other various organic solvent-water systems, and has good industrial application prospect.

The dehydration membrane reactor for methanol production from CO2 hydrogenation includes one or more porous supports, a dehydration membrane on the one or more porous supports, and a catalyst layer on the dehydration membrane. The one or more porous supports include hollow ceramic fibers and the dehydration membrane includes NaA zeolite. The reactor is made by dip-coating the porous supports in a zeolite crystal seed solution and drying the coated porous support. The coated porous support is dried at about 80° C. and then heated to a temperature above about 200° C. The NaA zeolite membrane is then grown on the seeded support, and a catalyst layer is applied to the zeolite membrane. A feedstream including carbon dioxide and hydrogen is fed to the catalyst layer, where a product stream including methanol and water is evolved. The water is then removed from the product stream through the dehydration membrane to produce a high-purity methanol product.

This invention belongs to the field of membrane separation technology, specifically relating to a method for preparing a Silicalite-1 zeolite membrane and its application. The method involves preparing sizable and highly crystallizable sheet-like and disc-shaped Silicalite-1 crystals, which are then sequentially coated onto a rough macroporous support surface to form a seed double layer. A composite template agent, such as bis-[1,5-(tripropylammonium)]pentamethylene diiodide, is introduced to regulate the crystallization and growth of the Silicalite-1 zeolite membrane, resulting in a continuous and dense thin-film Silicalite-1 membrane exhibiting high selectivity for N₂ / SF₆. The Silicalite-1 zeolite membrane of this invention demonstrates excellent sieving performance for N₂ and SF₆, which have significantly different kinetic diameters, making it particularly suitable for SF₆ recovery and inert gas purification in industrial waste gas. This method is simple and operates under mild conditions, making it valuable for energy conservation and environmental protection.

The application discloses a zeolite membrane for efficient separation of CO2 and a preparation method and application thereof. The zeolite membrane is prepared by encapsulating organic guest molecules (or ions) in the channels of the zeolite membrane, and then further regulating the structure and content of the organic guest molecules to obtain the zeolite membrane. Since the residual organic guest molecules have strong interaction with CO2, the diffusion rate of CO2 in the zeolite membrane is greatly reduced, and finally the efficient separation between CO2 and other gas mixtures can be realized. Compared with the conventional zeolite membrane, the zeolite membrane can be used for the separation of CO2 in various different mixture systems, and the application field is very wide, and the adaptability is greatly improved.

The invention discloses a ZSM-5 zeolite membrane synthesized with the assistance of a pore channel filler and a preparation method and application thereof.The preparation method comprises the following steps that S1, a silicon source, an aluminum source, an alkali source, the pore channel filler and deionized water are mixed and stirred to be uniform, and a synthetic solution is obtained, specifically, the pore channel filler comprises triethylene glycol; s2, putting the carrier of which the surface is pre-coated with the seed crystal into a synthetic solution for crystallization to generate a related film layer, taking out a film material after crystallization is finished, and washing and drying the film material; and S3, activating the membrane material to remove the pore filling agent in the pore channels of the membrane so as to prepare the porous ZSM-5 zeolite membrane. According to the method, the green and low-cost triethylene glycol is used for replacing an organic ammonium template agent to synthesize the ZSM-5 zeolite membrane, the prepared zeolite membrane is good in grain intergrowth, the grain boundary defect in the ZSM-5 zeolite membrane is remarkably reduced, and the ZSM-5 zeolite membrane shows excellent separation performance in pervaporation dehydration and gas separation.

The application discloses a kind of MFI type zeolite membrane and its preparation method, belong to membrane separation technical field.The method includes: the open hole MFI zeolite nanosheet is deposited on the surface of polymer porous carrier and forms seed layer, then sequentially carried out silicon source vapor treatment and ammonia steam treatment, induce adjacent nanosheet to occur fusion growth, and in-situ form dense continuous MFI zeolite membrane layer on the surface of polymer carrier.The polymer carrier is selected from nylon, PVDF, PP or PES, silicon source is tetraethyl orthosilicate or methyl orthosilicate, ammonia concentration is 2-8 wt.%, and processing temperature is 50-120 DEG C, without high-temperature calcination in whole process.The application solves the problem that high-temperature calcination destroys polymer carrier in the preparation of traditional MFI membrane, and realizes the effective fusion of MFI nanosheet under low temperature condition.The separation factor of the obtained membrane to n-butane / isobutane can reach 19.13, and the n-butane permeation rate is higher than 1.3*10 ‑7 mol·m ‑2 ·s ‑1 ·Pa ‑1 , with good application prospect.

This invention provides a method for separating ammonia gas from a mixed gas containing ammonia gas by making the permeation side of the zeolite membrane below atmospheric pressure, thereby allowing ammonia gas to permeate the zeolite membrane with high permeability and high separation selectivity. [Solution] A method for separating ammonia from a mixed gas consisting of at least ammonia using an ammonia separation membrane, comprising an ammonia separation step of supplying the mixed gas to an ammonia separation membrane and separating ammonia from the mixed gas by the ammonia separation membrane, wherein the pressure on the permeate side of the ammonia separation membrane is less than atmospheric pressure, and the ammonia separation membrane is a zeolite membrane, and the Si / Al2 molar ratio of the zeolite constituting the zeolite membrane is 40 or less.

The invention belongs to the technical field of membrane separation, and relates to a preparation method of a zeolite membrane for separating carbon dioxide. According to the method, a heterogeneous crystal seed FAU type molecular sieve and an AEI type molecular sieve have the same secondary structure unit SBU (d6r) to induce growth of an AEI phase in a membrane layer, firstly, a cheap macroporous carrier is pre-coated with an FAU crystal seed layer, and the AEI type zeolite molecular sieve membrane prepared by adopting a heterogeneous crystal seed secondary hydrothermal growth method has certain separation stability. The prepared AEI type zeolite molecular sieve membrane can be used for efficiently separating CO2 / CH4.

The invention relates to the technical field of zeolite membrane preparation, in particular to a method for rapidly preparing an SSZ-13 zeolite membrane through a Na2S2O8 auxiliary strategy, and the method is suitable for efficient separation of gas mixtures such as CO2 / CH4 and the like. The invention provides a method for rapidly preparing an SSZ-13 zeolite membrane by using a Na2S2O8 auxiliary strategy and accurately controlling a matching index of a seed crystal size and a carrier aperture within an optimization interval of 0.5-1.0, and solves the problems of long synthesis time, non-uniform membrane quality and difficulty in large-scale production in the prior art.

This invention belongs to the field of inorganic membrane separation technology, specifically relating to a method for preparing a hierarchical porous zeolite membrane formed by the symbiosis of MFI and MEL, and its application. Symbiotic seed crystals are prepared using raw materials including SiO2, TBAOH, and water. These seed crystals are dispersed in anhydrous ethanol to obtain a seed crystal suspension. A preheated carrier is immersed in the seed crystal suspension for coating, calcined and solidified, and then immersed in a synthesis mother liquor formed by a mixture of SiO2, TBAOH, and water. A hydrothermal reaction is then performed to synthesize a zeolite membrane, which is dried, calcined, and cooled to obtain the hierarchical porous zeolite membrane. This hierarchical porous zeolite membrane can be used as a preferential pervaporation membrane for biomass ethanol under relatively low temperature conditions. Experimental results show that 2-5 nm mesopores are successfully introduced into the microporous zeolite membrane. The increased porosity reduces the mass transport path and transport resistance. When applied to the pervaporation separation of biomass ethanol, the membrane exhibits a significantly reduced decrease in long-term pervaporation flux.

The invention belongs to the technical field of membrane separation, and discloses a recycling and reusing method of waste synthetic liquid after MFI zeolite membrane reaction. The method comprises the following steps: collecting waste synthetic liquid after MFI zeolite membrane synthesis reaction, and removing possible large-particle impurities through simple physical separation means such as standing, centrifuging or filtering to obtain stable suspension rich in MFI crystals, and directly using the suspension as seed crystal liquid for next MFI membrane synthesis. According to the method, a complicated purification or retreatment process is not needed, and in-situ and all-component recovery of the waste synthetic liquid is realized. The method has the beneficial effects that the consumption of fresh seed crystals and chemical raw materials in the preparation process of the MFI film is greatly reduced, and the production cost is saved; meanwhile, the discharge of organic waste liquid is reduced, and the method is environment-friendly; the recycled seed crystal liquid is high in activity, when the seed crystal liquid is used for secondary synthesis, the prepared MFI membrane still has good continuity and separation performance, and an effective way is provided for achieving green, low-cost and sustainable manufacturing of the MFI membrane material.

The invention discloses a preparation method of a zeolite crystal membrane with nanoscale thickness, which comprises the following steps: (1) spin-coating a thin layer: spin-coating a crystallite solution of a zeolite membrane on the surface of a substrate to form a thin solution layer; (2) quick freezing: quickly putting the substrate subjected to thin-layer spin-coating into a cold source environment for freezing treatment, and enabling one surface with a thin solution layer to be in contact with a cold source at first; (3) heating and synthesizing: taking out the substrate after freezing, melting and air-drying, enabling the surface of the substrate with the thin solution layer to face upwards, integrally soaking the substrate in a crystallite solution, and heating to enable seed crystals on the surface of the substrate to grow by heating; and (4) carrying out calcination treatment to remove the template agent brought by the crystallite solution so as to obtain the zeolite crystal membrane with the nanoscale thickness. The zeolite crystal membrane prepared by the method has the advantages that the thickness is obviously reduced to nanoscale, the crystal height is orderly arranged, the consistency is good, and the separation efficiency, the stability and the mechanical strength are obviously improved.