1525results about "Pentasil aluminosilicate zeolite" patented technology

The present invention relates to preparation process of adhesive-free ZSM type molecular sieve, and aims at solving the problem of adding adhesive causing decrease in effective surface area and limited diffusion. Technologically, the present invention is that adhesive silica in 5-50 wt% and ZSM type molecular sieve powder are made to form mixture, and the mixture is hydrothermally converted inside water solution or steam containing organic amine halide and alkyl diamine into integrated ZSM type molecular sieve. The process of the present invention may be used in the industrial preparation of ZSM type molecular sieve catalyst.

The preparation process of small crystal grain ZSM-5 zeolite includes the following steps: mixing alumino sillica gel grain in SiO2/Al2O3 molar ratio of 20-600 and granularity of 20-300 mesh and water solution of organic template agent, and hydrothermal crystallization of the mixture with or without ZSM-5 zeolite crystal seed; and once filtering, drying and roasting. The said process can preparing ZSM-5 zeolite product with Si/Al molar ratio of 15-200 and initial crystal granularity of 0.1-0.5 micron. The process uses no sodium ion material, needs no ammonium exchange, filtering and roasting process, and thus has high zeolite product yield and simplified production process. The zeolite product is used in the catalyst for hydrolyzing cyclohexene to prepare cyclohexanol and has high cyclohexanol converting rate.

The invention discloses a synthetic method for ZSM-5/mordenite mixed crystal material, wherein ZSM-5 molecular sieve is charged into the synthesized reaction mixture of mordenite as seed crystal, and said material is prepared through water thermal crystallization. The invention realizes low making cost and more ideal catalyzing performance.

The invention relates to a synthesis method of fine grain ZSM-5 zeolite molecular sieve with high silicon aluminium ratio, which comprises using a surface active agent, charging it into acidified aluminium salt solution, then slowly dropping alkaline solution formed from sodium silicate, template agent and seed crystal into aluminium saline solution, the overall composition of the obtained reaction mixture being Na2O:Al2O3:SiO2:H2O=1.5-4.0:1:20-280:500-2000 by mol ratio, then subjecting the reaction mixture to thermal crystallization through the conventional method.

A loudspeaker device (200) is presented which includes a zeolite material (100) comprising zeolite particles (102) having a silicon to aluminum mass ratio of at least 200. For an increased pore fraction of pores with a diameter in a range between 0.7 micrometer and 30 micrometer shows an increased shift of the resonance frequency down to lower frequencies has been observed.

The invention relates to a preparation method of a nano-ZSM-5 molecular sieve, which belongs to the field of preparation of zeolite molecular sieve catalysts. The preparation method can solve the problem that the existing synthesis technology has the defects of easy emergence of mixed crystal phase, high cost, environmental pollution and easy loss of features of nanomaterials. The method is as follows: adding pre-crystallized crystal seeds into a gel system of the template-free synthetic nano-ZSM-5 molecular sieve, carrying out crystallization for 24 hours at the temperature of 160-180 DEG C,cooling to room temperature, carrying out centrifugal filtration on products, washing, drying and baking. The prepared nano-ZSM-5 molecular sieve is highly concentrated nanoscale crystals without themixed crystal phase; and the method has the advantages of low cost and environmental protection.

The invention provides a preparation method for small-size ZSM-5 molecular sieve. Wherein, using pearlite and montmorillonite as material for aluminum, adding crystal seed for crystallization reaction on hydrothermal condition, and obtaining a small-size product with 5~95% ZSM-5 that can be used to prepare modified ZSM-5 molecular sieve by different post-treatment method or as the active intergradient or carrier for catalyst. This invention cuts the cost more.

The invention provides a ZSM-5 type molecular sieve for a catalyst for a reaction for preparing propylene from methanol and/or dimethyl ether, which has a silica alumina ratio of 250-1,150 and a grain diameter of 65-250nm. A preparation method of the molecular sieve comprises the following steps: (1) mixing an aluminum source and an organic directing agent and stirring an obtained mixture at constant temperature of 0-30 DEG C for 2-24 hours; (2) adding a silicon source and an organic addition agent to the mixed solution obtained in the step (1) and continuing stirring the mixed solution to obtain gel; (3) stirring the gel obtained in the step (2) at 35-95 DEG C and then carrying out a crystallization reaction for 24-240 hours at 60-200 DEG C, wherein in the raw materials for synthesizing the molecular sieve, and the molar ratio of OH<-1> to SO2 to AL2O3 to H2O to the organic directing agent to the organic directing agent is (0.1-0.35):1:(0.0005-0.01):(10-25):(0.1-0.6):(0.5-8). The ZSM-5 type catalyst has the characteristics of controllable grain size, adjustable silica alumina ratio, high dispersity, and the like and has higher propylene selectivity and P/E ratio in the reaction for preparing low carbon olefin from the methanol and/or the dimethyl ether.

The invention relates to ZSM-5 molecular sieve with small crystal grains and application thereof, mainly solving the technical problems that the silica-alumina molar ratio (SiO2/Al2O3) of ZSM-5 molecular sieves with small crystal grains is less than 200, and the traditional ZSM-5 molecular sieves have poor catalyst stability and short service life when used for reaction for preparing propylene from methanol in the prior art. The invention well solves the problems by the technical scheme that the ZSM-5 molecular sieve with small crystal grains, which has a crystal diameter less than 300 microns and a SiO2/Al2O3 molar ratio not less than 200, is used for reaction for preparing the propylene from the methanol. The invention can be used in industrial production for preparing the propylene from the methanol.

Provided is a method of preparing a ZSM-5 catalyst for preparing light olefins including ethylene and propylene through a catalytic cracking of a hydrocarbon mixture of C4 to C7 produced after a naphtha cracking. The method includes (a) forming a gel by aging a mixture solution including a silica precursor and an aluminum precursor; (b) adding a template possibly forming mesopores through a heat treatment, into the gel, stirring and then aging; (c) forming a solid product by crystallizing the aged mixture in step (b); and (d) heat treating the solid product to remove the template. The ZSM-5 catalyst may include micropores and mesopores and may have good physical and chemical properties along with a good pore property. The production yield of the light olefins may be increased.

The invention discloses a preparation method of a mesoporous-microporous composite molecular sieve. The preparation method comprises the following steps of adding a microporous molecular sieve subjected to hydrothermal treatment into a mixed system of a silicon source, an acid solution and a surfactant, then carrying out crystallization, filtration and washing, and then carrying out drying and calcination to obtain the mesoporous-microporous composite molecular sieve. The preparation method fully utilizes non-framework aluminum falling from the microporous molecular sieve, avoids an aluminum source used by the conventional molecular sieve preparation technology, is conducive to improvement of a silica-alumina ratio of the mesoporous-microporous composite molecular sieve, realizes a high degree of crystallization, and improves hydrothermal stability and thermostability of the mesoporous-microporous composite molecular sieve. The mesoporous-microporous composite molecular sieve is suitable for the field of macromolecule catalysis, is conducive to improvement of a reaction conversion ratio and reaction selectivity, and is especially suitable for being used in a cracking catalyst for maximum-degree production of middle distillate from heavy oil as a raw material.

The invention belongs to the synthesis field of aluminosilicate ZMS (Zeolite Molecular Sieve), and relates to a synthetic method of ZSM-5 zeolite molecular sieves. ZSM-5 zeolites are high-silicon micro-porous zeolites with unique three-dimensional ten-membered ring crossing aperture passages, the diameters of the aperture passages are close to the sizes of benzene rings, and the ZSM-5 zeolites can be widely applied to petroleum refining, petrochemical industry and fine chemicals synthesis. Particularly, nano-sized ZSM-5 zeolites achieve larger external surface area and higher intracrystalline diffusion rate, and have higher activity and selectivity as well as strong coking deactivation-resisting capability in hydrocarbons catalysis conversion reactions. The synthetic method regulates the polymerization degrees of silicon sources and aluminum sources respectively by adding acid and alkali so as to obtain highly reactive reactants, and can rapidly achieve nucleus formation in large quantities in a system so as to obtain nano-sized zeolites. The synthetic method is not limited by the types of the silicon sources and the aluminum sources, has strong applicability to raw materials, changes the activity of the raw materials through simple regulation, and can rapidly synthesize products of the nano-sized ZSM-5 zeolites with well crystallinity under the dosage conditions of no template and low-cost templates.

The invention provides a process for synthesizing ZSM-5, characterized in that, diatomaceous soil is used as a silicon source, and total or part of aluminum source to be mixed with other aluminum source, NaOH and water, 0-10 wt.% molecular sieve is added in as seed crystal to prepare slurry of reaction mixture, performing water thermal crystallization in normal condition. The process can reduce gelatification, increase solid content and reduce the cost.

The invention discloses a nano ZSM-5 molecular sieve based catalyst and preparation and use methods. The molecular sieve catalyst consists of molecular sieves and metal components, wherein the molecular sieves are nano ZSM-5 molecular sieves with a short b-axis, a medium high silica-alumina ratio, less strong acid, high Lewis acid content, and resistance to hydrothermal deactivation. The preparation method is as follows: mixing a silicon source, an aluminum source, a template agent, a structure promoter, an additive and alkali with water, and stirring to prepare a precursor solution, then crystallizing, separating solid from liquid, and calcinating to obtain molecular sieve raw powder; mixing the molecular sieve raw powder with an ammonium salt solution, stirring, filtering, mixing with the ammonium salt solution for several times, stirring, filtering, and calcinating to obtain hydrogen-type ZSM-5 molecular sieves; mixing with the metal precursor solution, drying and calcinating to obtain the aromatization catalyst. The use method is as follows: transforming oxy-compound raw materials to aromatic hydrocarbon through the catalyst under the reaction conditions. The nano ZSM-5 molecular sieve based catalyst has the characteristics of being high in aromatics yield (reaching up to 99%) and long in service life (the catalyst is alive after 300 hours, and the aromatics selectivity reaches up to 70% after the catalyst is subjected to hydrothermal aging at 760 DEG C for 4 hours).

The invention relates to a preparation method of kaolin in situ crystallization ZSM-5 molecular sieves and is characterized in that the internal and external surfaces of modified kaolin are provided with ZSM-5 molecular sieves by in situ crystallization; calculated by relative crystallinity, the relative content of the ZSM-5 molecular sieves in the kaolin is 30-80 %. The in situ crystallization ZSM-5 molecular sieves of the invention have the advantages of high crystallinity, small crystal grain, high activity and good stability.

A method for producing zeolite films or membranes at essentially ambient pressure, which includes preparing a synthesis mixture comprising an ionic liquid solvent and an aluminum and/or silicon and/or phosphate source and converting the synthesis mixture to form a continuous zeolite layer. In addition, a method of synthesizing zeolite nanocrystals, which includes preparing a synthesis mixture, the synthesis mixture having a silica or a silica and alumina source, and a template; and synthesizing the synthesis mixture to form zeolite nanocrystals.

The invention relates to a method for preparing hollow zeolite socony mobil-5 (ZSM-5) nanometer zeolite. The method is characterized by comprising the following steps of: mixing single-dispersion ZSM-5 nanometer zeolite of which the silicon-aluminum molar ratio of SiO2/Al2O3 is over 20 and the partical size ranges from 100 to 400 nanometers with 0.05 to 0.5 mol/L of an aqueous solution of alkaline substances, wherein the alkaline substances are selected from a mixture in which a molar ratio of quaternary ammonium salt to sodium hydroxide is 1:1, a mixture in which a molar ratio of the quaternary ammonium salt to potassium hydroxide is 1:1, n-butylamine and quaternary ammonium base; and stirring at the temperature of between 80 and 200 DEG C for 10 to 200 hours, and separating. By the method, a regular cavity structure is formed, so that reactants and products are easy to transfer, and the crystallinity is high; and the method is simple, low in cost and high in yield, and can be used for mass production. The hollow ZSM-5 nanometer zeolite with different silicon-aluminum ratios can be obtained by using different matrixes or under different treatment conditions, and the sizes of cavities of hollow ZSM-5 nanometer zeolite can be regulated by changing the treatment condition.

The preparation process of ZSM-5 molecular sieve of nanometer size and containing hetero atom includes adding alkali metal salt; adding additive, template agent, one of Al and hetero atoms in certain order and at 60-120 deg.c for mixing with Si source; and crystallization statically or under stirring for 1-15 days. The molecular sieve has crystal grain size of 40-200 nm, and specific surface area of 300-600 sq m/g. The present invention has the advantages of optional static or dynamic synthesizing condition, no-toxic operation, controllable crystal grain size and skeleton hetero atom, various kinds of metal atom, low crystallization temperature and simple operation. The present invention provides some optional materials for developing catalyst with industrial application foreground and has great application value.

The invention relates to a method for preparing ZSM-5 zeolite through in-situ crystallization, which comprises that: kaolin slurry containing kaolin, adhesive and water is prepared into kaolin microspheres through spray drying, and the prepared kaolin microspheres are baked; silicon-enriched clay slurry containing silicon-enriched clay, adhesive and water is prepared into silicon-enriched clay microspheres through spray drying, and the prepared silicon-enriched clay microspheres are baked; and the respectively baked kaolin microspheres and silicon-enriched clay microspheres are mixed with a water solution containing alkali, and the mixture is subjected to in-situ hydrothermal crystallization to obtain crystallization product, wherein the mol ratio of SiO2 to Al2O3 in the silicon-enriched clay is more than 2. The ZSM-5 zeolite prepared by the method has high content of zeolite and rich middle holes, so the ZSM-5 zeolite can be used as a catalyst in the field of petrochemical industry.

The present invention relates to a process for the preparation of doped pentasil-type zeolite, which process comprises the steps of:

• a) preparing an aqueous precursor mixture from a silicon source, an aluminium source, and doped non-zeolitic seeds; and
• b) thermally treating the precursor mixture to form a doped pentasil-type zeolite.

The term “non-zeolitic seeds” includes seeds made from materials selected from the group consisting of (i) X-ray amorphous materials, (ii) milled crystalline materials, such as milled zeolites, that have a relative crystallinity of not more than 75%, and (iii) crystalline materials other than zeolites, such as clays (e,g, bentonite and kaolin) and (low) crystalline aluminas.

The invention relates to a method for preparing a ZSM (Zeolite Socony Mobil)-5 in a grade structure, and specifically relates to a method for preparing a grade porous ZMS-5 molecular sieve by acid-base coupling. The method comprises the following steps: mixing commercial ZSM-5 and alkali liquor in proportion, and heating and stirring to form a suspension; filtering the suspension; washing the filter cakes by water or acidic liquor; and finally, carrying out ion exchange by using acidic ammonium salt liquor; and then, roasting to obtain the grade porous ZMS-5 molecular sieve. The method provided by the invention aims to prepare the ZSM-molecular sieve rich in secondary mesopores. Firstly, part of aluminum silicon species in the ZSM-5 is removed in an environment-friendly alkali treatment manner to prepare the ZSM-5 molecular sieve with a secondary pore structure. Based on the secondary pore formed, undefined structures on the surface of the ZSM-5 and in the duct are dissolved out by way of acid washing or ion exchange. Meanwhile, the pore volume and the specific surface area of the secondary mesopore-enriching ZSM-5 molecular sieve are improved. Through the acid-base coupling treatment, the distribution state of aluminum outside the framework on the surface of the ZSM-5 is improved, so that the secondary mesopore-enriching ZSM-5 molecular sieve prepared by the method has a huge application potential in catalytic cracking and hydrocracking.