JP4834989B2 - Novel structure containing aluminosilicate and process for producing the same - Google Patents

Description

  The present invention relates to a novel structure containing aluminosilicate and a method for producing the same. More specifically, the present invention relates to a structure including a crystalline porous aluminosilicate in a structure surface layer portion and an aluminosilicate in which an inert carrier is present inside the structure surface layer portion, and a method for manufacturing the structure.

  Crystalline porous aluminosilicate is a kind of zeolite, and its composition is generally represented by the following formula (1).

_{xM 2 / n O · Al 2} O 3 · ySiO 2 · zH 2 O (1)
(Here, n is the valence of the cation M, x is a number in the range of 0.8 to 2, y is a number of 2 or more, and z is a number of 0 or more.)
The basic structure consists of a tetrahedral structure represented by SiO ₄ in which four oxygens are arranged at the apex centered on silicon, and a tetrahedron represented by AlO ₄ having aluminum in the center instead of silicon. / (Silicon + aluminum) is a three-dimensionally bonded structure that shares oxygen with each other such that the atomic ratio is 2.

  As a result, a three-dimensional skeleton structure having pores of different sizes and shapes is formed by the difference in the bonding method of the tetrahedron.

  Crystalline porous aluminosilicate is known to have solid acidity. The tetrahedron centered on aluminum is negatively charged, and is electrically neutralized by binding to cations such as protons, alkali metals, and alkaline earth metals. In particular, when it is combined with protons, it exhibits Bronsted acidity, and thus crystalline porous aluminosilicate is used as a solid acid catalyst. That is, it is used as a catalyst for catalytic cracking, hydrocracking, aliphatic or aromatic isomerization reaction, disproportionation reaction, and the like.

  The crystalline porous aluminosilicate is obtained by hydrothermal synthesis of an aqueous slurry prepared using a silicon source, an aluminum source, an alkali metal component, and a structure-directing agent such as nitrogen-containing or phosphorus-containing compound. In the conventional production method, the obtained crystalline porous aluminosilicate is a powder, and when a structure containing aluminosilicate is produced, the crystalline porous aluminosilicate alone cannot be obtained because the moldability is poor. It is necessary to add an inorganic binder to the obtained powder to produce a structure containing aluminosilicate.

  As a method for producing a structure containing an aluminosilicate using a zeolite as a binder, for example, firstly, a first crystal of zeolite is produced, and this crystalline powder is mixed and molded with silica gel or sol, and then added silica gel or sol. (For example, refer to Patent Document 1).

  As a method for producing a crystalline porous aluminosilicate structure not containing a binder, for example, a silica structure is used as a silicon source, and an aluminate, an alkali metal component, and a tetraalkylammonium component are supported on the silica structure, And a method for producing a crystalline aluminosilicate having an MFI, MTW, RUT, BEA, or MEL structure (for example, see Patent Documents 2 to 6).

  In these methods, aluminum atoms are present throughout the structure, and as a result, acid sites are also present throughout the structure.

  As a method for allowing zeolite to be present in the surface layer of the catalyst structure, for example, the surface layer of a granular solid catalyst such as a metal catalyst, an alloy catalyst, or an inorganic oxide catalyst has a molecular sieving action, and the entire surface is made of a substantially inert zeolite membrane. (For example, refer patent document 7). In this case, the zeolite layer on the surface of the structure is an inert silicalite having no acid sites.

JP-T-2001-504084 (page 10) JP 2001-58817 A (page 3) JP 2001-114512 A (page 3) JP 2001-139323 A (page 3) JP 2001-139324 A (page 3) JP 2001-180928 A (page 3) JP 2003-62466 A (page 3)

  However, since the crystalline porous aluminosilicates of Patent Documents 1 to 6 have active sites such as acid sites in the entire structure or inside the structure, the reaction raw materials and reaction products in the solid acid catalytic reaction are pores. Pass through the structure. Therefore, the residence time inside the structure of the reaction raw materials and reaction products is prolonged, the excess reaction proceeds at the active sites, etc., the selectivity of the target product is lowered, and the high boiling point such as coke becomes active sites and fines of the catalyst. It precipitates in the pores, resulting in poisoning of active sites and clogging of the pores, resulting in problems such as a decrease in catalyst activity and a further decrease in catalyst life.

  Further, in the method of Patent Document 7, since the entire surface is coated with a zeolite membrane that has a molecular sieving action on the active point of the catalyst and is substantially inactive, the reaction raw materials and reaction products in the reaction can be converted into zeolite pores. It is necessary to enter the structure through. Also in this case, the residence time inside the structure of the reaction raw materials and reaction products is prolonged, the selectivity of the target product is lowered, high boiling substances such as coke are deposited, poisoning of active sites and pore clogging. As a result, problems such as a decrease in catalyst activity and a decrease in catalyst life occur.

  In order to solve these problems, a zeolite structure in which the reaction product immediately leaves from an acid site, that is, a site having an active site, is required.

  The present invention has been made in view of the above problems, and its purpose is to provide a crystalline porous aluminosilicate in a structure surface layer portion effective as a solid acid catalyst, and an inert carrier inside the structure surface layer portion excluding the structure surface layer portion. It is to provide an existing structure and a method for producing the same.

  As a result of intensive studies to solve the above problems, the present inventors have found a novel structure containing aluminosilicate and have completed the present invention.

That is, the present invention relates to a structure in which a crystalline porous aluminosilicate having an MTT type crystal structure is present in the structure surface layer portion, and an inert carrier is present inside the structure surface layer portion, and a method for producing the structure. It is.

  The novel structure containing the aluminosilicate of the present invention is characterized in that a crystalline porous aluminosilicate is present in the surface layer portion of the structure, and an inert carrier is present inside the structure surface layer portion. To do.

  Here, the structure in the present invention refers to an object molded so as to resist a load such as its own weight or external force.

  The crystalline porous aluminosilicate of the present invention is a kind of zeolite and zeolite-like substance, and is not particularly limited. The structure is a structure code defined by the International Zeolite Society, for example, ABW, AFG, ANA, * BEA, BIK, BOG, BRE, CAN, CAS, CFI, CHA, DAC, DDR, EAB, EDI, EMT, EPI, ERI, ESV, EUO, FAU, FER, FRA, GIS, GME, GOO, HEU, IFR, ITE, JBW, KFI, LAU, LEV, LIO, LOS, LTA, LTL, LTN, MAZ, MEI, MEL, MER, MFI, MFS, MON, MOR, MSO, MTF, MTN, MTT, MTW, MWW, NAT, NES, NON, OFF, -PAR, PAU, PHI, RHO, RT , RUT, SFE, SFF, SFG, SOD, SST, STF, STI, STT, TER, THO, TON, TSC, UFI, VET, VFI, -WEN, YUG, etc. Since it is a zeolite-like substance, preferably ANA, * BEA, CAS, CFI, DDR, EMT, EUO, FAU, FER, ITE, LEV, LTA, MAZ, MEI, MEL, MFI, MFS, MOR, MOS, MTF , MTN, MTT, MTW, MWW, NES, NON, OFF, RUT, SFE, SFF, SFG, SSY, STF, STT, TON, VFI, and more preferably MTT.

  The inner inert carrier excluding the structure surface layer portion of the present invention is a carrier that does not react with the reaction raw material as a solid acid catalyst, and examples thereof include silica, alumina, titania, and zirconia, and the surface layer portion has a high degree of crystallinity. Silica is preferred because silicate can be obtained.

  In the structure of the present invention, the thickness of the layer where the crystalline porous aluminosilicate is present in the surface layer of the structure is preferably 1 to 1000 μm, more preferably 1 to 500 μm from the outer surface of the structure.

  In the structure of the present invention, the aluminum / silicon ratio (atomic ratio) of the crystalline porous aluminosilicate in the surface layer portion of the structure is preferably 0.0001 to 1 because a structure with a high degree of crystallinity can be obtained. More preferably, it is 0.0005 to 0.5.

  The shape of the structure of the present invention is not particularly limited, and examples thereof include a spherical shape, an elliptical shape, a cylindrical shape, a hollow cylindrical shape, a plate shape, a sheet shape, and a honeycomb shape as shown in FIGS. Preferably, it is spherical, elliptical, cylindrical, hollow cylindrical, more preferably spherical, because it has sufficient reaction activity and can suppress side reactions and coking.

  In addition, the size of the structure of the present invention is not particularly limited. For example, since there is sufficient reaction activity and side reactions and coking can be suppressed, preferably in the range of 10 μm to 10 cm, More preferably, a structure in the range of 100 μm to 5 cm is used.

  In the structure of the present invention, the presence or absence of a binder is not particularly limited.

  The structure of the present invention can be produced by any method. For example, (1) after impregnating or supporting an inert carrier with a structure-directing agent such as an alkali metal, nitrogen-containing or phosphorus-containing compound as required. A method of carrying out a crystallization treatment by supporting an aluminum source and a silicon source on an inert carrier and bringing them into contact with water vapor or water vapor containing a structure-directing agent such as nitrogen-containing compound or phosphorus-containing compound, if necessary, (2) inert A method in which a carrier is added to a silica-alumina sol containing a structure-directing agent such as an alkali metal, nitrogen-containing or phosphorus-containing compound as required, and crystallized by hydrothermal treatment, (3) an alkali metal as an inert carrier, If necessary, apply silica-alumina sol containing a structure-directing agent such as nitrogen-containing or phosphorus-containing compound, and form water vapor or, if necessary, structure such as nitrogen-containing or phosphorus-containing compound Jozai brought into contact with water vapor contained can be manufactured by the manufacturing method such as a method of crystallizing process. Since an aluminosilicate having a high degree of crystallinity can be obtained in the surface layer portion of the structure, the method (1) is preferably used.

  In the present invention, the method (1) will be described in more detail. After impregnating or supporting a structure-directing agent such as an alkali metal and, if necessary, a nitrogen-containing or phosphorus-containing compound on an inert carrier, an aluminum source and a silicon source are added. It is supported on an inert carrier, and after drying, it is contacted with water vapor or water vapor containing a structure-directing agent such as nitrogen-containing or phosphorus-containing compound, if necessary. A structure is obtained in which aluminosilicate is present and an inert carrier is present inside the structure except for the surface layer. Furthermore, you may perform baking and ion exchange as needed. When the inert carrier is silica, the silica of the inert carrier serves as the silicon source, and it is not necessary to carry the silicon source. It is preferable to perform the crystallization treatment after impregnating or supporting an alkali metal on silica with an inert carrier and then supporting an aluminum source on the inert carrier.

The inert carrier used in the method of the present invention is not particularly limited. For example, silica, alumina, titania, zirconia can be used, and crystalline porous aluminosilicate is used for the surface layer portion of the structure. Since silica is easily formed, silica is preferably used. A commercially available inert carrier can be used. As the inert carrier, an aluminosilicate having a high degree of crystallinity can be obtained, so that the surface area is preferably 5 to 1000 m ² / g, more preferably 10 to 500 m ² / g.

  The shape of the inert carrier is not particularly limited, and for example, a spherical shape, an elliptical shape, a cylindrical shape, a hollow cylindrical shape, a plate shape, a sheet shape, a honeycomb shape, and the like are used. Since there is sufficient reaction activity and side reactions and coking can be suppressed, spherical, elliptical, cylindrical, hollow cylindrical, and more preferably spherical are used.

  In addition, the particle size of the inert carrier is not particularly limited, and for example, a particle having a size of preferably 10 μm to 10 cm, more preferably 100 μm to 5 cm is used.

  The silicon source used in the method of the present invention is not particularly limited. For example, water glass, colloidal silica, tetraalkoxysilane, silica gel and the like can be used, and silica which is an inert carrier. Can be used as a silicon source. Since an aluminosilicate having a high degree of crystallinity can be obtained in the surface layer portion of the structure, silica that is an inert carrier is preferably used as the silicon source.

  The aluminum source used in the method of the present invention is not particularly limited. For example, aluminum salts such as aluminum chloride, aluminum nitrate, aluminum sulfate, and aluminum carbonate; lithium aluminate, sodium aluminate, potassium aluminate Aluminum aluminates such as rubidium aluminate and cesium aluminate; aluminum alkoxides such as aluminum methoxide, aluminum ethoxide, aluminum propoxide and aluminum butoxide are used. Preferably, aluminum salts are used, and aluminum nitrate and aluminum sulfate are more preferably used because the aluminum source supported on the surface layer of the carrier does not easily diffuse inside.

  The alkali metal used in the method of the present invention is not particularly limited. For example, hydroxides such as lithium hydroxide, sodium hydroxide, potassium hydroxide, rubidium hydroxide, cesium hydroxide; Carbonates such as lithium, sodium carbonate, potassium carbonate, rubidium carbonate, cesium carbonate; acetates such as lithium acetate, sodium acetate, potassium acetate, rubidium acetate, cesium acetate; lithium chloride, sodium chloride, potassium chloride, rubidium chloride, Chlorides such as cesium chloride; nitrates such as lithium nitrate, sodium nitrate, potassium nitrate, rubidium nitrate, and cesium nitrate are used. When using an alkali metal component other than a hydroxide, it is preferable to carry out baking before supporting the aluminum source on the inert carrier to form an oxide.

  The structure directing agent used in the present invention is not particularly limited, and is, for example, a nitrogen-containing or phosphorus-containing compound, such as methylamine, ethylamine, n-propylamine, isopropylamine, n-butylamine, Isobutylamine, n-pentylamine, n-hexylamine, pyridine, diaminoethane, diaminopropane, diaminobutane, diaminopeptane, diamine hexane, dimethylamine, diethylamine, di-n-propylamine, di-n-butylamine, di -N-pentylamine, di-n-hexylamine, diphenylamine, trimethylamine, triethylamine, tri-n-propylamine, triisopropylamine, tri-n-butylamine, tri-n-pentylamine, tri-n-hexylamine, triphenyl Ruamine, dimethylethylamine, dimethyl-n-propylamine, dimethylisopropylamine, dimethyl-n-butylamine, dimethylisopropylamine, dimethyl-n-pentylamine, dimethyl-n-hexylamine, dimethylphenylamine, diethylmethylamine, di- n-propylmethylamine, diisopropylamine, di-n-butylmethylamine, diisobutylamine, di-n-pentylmethylamine, di-n-hexylmethylamine, diphenylmethylamine, aziridine, azetidine, pyrrolidine, 1-methylpyrrolidine 1-ethylpyrrolidine, 1-n-propylpyrrolidine, 1-isopropylpyrrolidine, 1-n-butylpyrrolidine, 1-isobutylpyrrolidine, 1-n-pentylpyrrolidine, 1-n-hex Rupyrrolidine, 1-phenylpyrrolidine, piperidine, 1-methylpiperidine, 1-ethylpiperidine, 1-n-propylpiperidine, 1-isopropylpiperidine, 1-n-butylpiperidine, 1-isobutylpiperidine, 1-n-pentylpiperidine, 1-n-hexylpiperidine, 1-phenylpiperidine, pyrrole, 1-methylpyrrole, 1-ethylpyrrole, 1-n-propylpyrrole, 1-isopropylpyrrole, 1-n-butylpyrrole, 1-isobutylpyrrole, 1- n-pentylpyrrole, 1-n-hexylpyrrole, 1-phenylpyrrole, pyridine, 1-methylpyridine, 1-ethylpyridine, 1-n-propylpyridine, 1-isopropylpyridine, 1-n-butylpyridine, 1- Isobutylpyridine, 1-n-pe Organic amine compounds such as nthylpyridine, 1-n-hexylpyridine, 1-phenylpyridine; tetramethylammonium, tetraethylammonium, tetra-n-propylammonium, tetraisopropylammonium, tetra-n-butylammonium, tetraisobutylammonium, tetra -N-pentylammonium, tetra-n-hexylammonium, tetraphenylammonium, trimethylethylammonium, trimethylethylammonium, trimethyl-n-propylammonium, trimethylisopropylammonium, trimethyl-n-butylammonium, trimethylisobutylammonium, trimethyl-n -Pentylammonium, trimethyl-n-hexylammonium, trimethylphenylammo Dimethyl, diethyldimethylammonium, dimethyldiammonium, dimethyl-di-n-propylammonium, dimethyldiisopropylammonium, dimethyldi-n-butylammonium, dimethyldiisobutylammonium, dimethyldi-n-pentylammonium, dimethyldi-n-hexylammonium, dimethyldiphenyl Ammonium, methyltriethylammonium, methyltriammonium, methyltri-n-propylammonium, methyltriisopropylammonium, methyltri-n-butylammonium, methyltriisobutylammonium, methyltri-n-pentylammonium, methyltri-n-hexylammonium, methyltri Phenylammonium, hydroxymethyltrimethylammonium, 2- Droxyethyltrimethylammonium, 3-hydroxy-n-propyltrimethylammonium, 4-hydroxy-n-butyltrimethylammonium, 5-hydroxy-n-pentyltrimethylammonium, 6-hydroxy-n-hexyltrimethylammonium, 3-hydroxyphenyl Ammonium salts such as halides and hydroxides such as trimethylammonium; tetramethylphosphonium, tetraethylphosphonium, tetra-n-propylphosphonium, tetraisopropylphosphonium, tetra-n-butylphosphonium, tetraisobutylphosphonium, tetra-n-pentyl Phosphonium, tetra-n-hexylphosphonium, tetraphenylphosphonium, trimethylethylphosphonium, trimethylethylphospho , Trimethyl-n-propylphosphonium, trimethylisopropylphosphonium, trimethyl-n-butylphosphonium, trimethylisobutylphosphonium, trimethyl-n-pentylphosphonium, trimethyl-n-hexylphosphonium, trimethylphenylphosphonium, dimethyldiethylphosphonium, dimethyldiphosphonium, Dimethyl-di-n-propylphosphonium, dimethyldiisopropylphosphonium, dimethyldi-n-butylphosphonium, dimethyldiisobutylphosphonium, dimethyldi-n-pentylphosphonium, dimethyldi-n-hexylphosphonium, dimethyldiphenylphosphonium, methyltriethylphosphonium, methyltriphosphonium, Methyltri-n-propylphosphonium, methyl Riisopropylphosphonium, methyltri-n-butylphosphonium, methyltriisobutylphosphonium, methyltri-n-pentylphosphonium, methyltri-n-hexylphosphonium, methyltriphenylphosphonium, hydroxymethyltrimethylphosphonium, 2-hydroxyethyltrimethylphosphonium, 3-hydroxy Halides such as -n-propyltrimethylphosphonium, 4-hydroxy-n-butyltrimethylphosphonium, 5-hydroxy-n-pentyltrimethylphosphonium, 6-hydroxy-n-hexyltrimethylphosphonium, 3-hydroxyphenyltrimethylphosphonium, water Phosphonium salts such as oxides; etc. are used. Since an aluminosilicate having a high degree of crystallinity can be obtained, organic amines, ammonium salts, and more preferably pyrrolidine is preferably used.

  In the present invention, the order of impregnation or loading of the silicon source, the aluminum source, the alkali component, and the structure directing agent on the inert carrier is not particularly limited. Since an aluminosilicate having high crystallinity can be obtained in the structure surface layer portion, the order of alkali metal, structure directing agent, and aluminum source is preferable. The order of loading the silicon source on the inert carrier is not particularly limited, and may be before the alkali metal is loaded or simultaneously with the aluminum source.

  In the present invention, the method for supporting an alkali metal on an inert carrier is not particularly limited, but a conventionally known method for supporting a metal component on an inert carrier or the like, for example, an impregnation method, a deposition method, an ion exchange method, or the like. Laws are used. If necessary, drying and baking may be performed. The amount of alkali metal supported on the inert carrier is not limited. For example, the alkali metal is 0.0001 to 50% of the weight of the inert carrier, and an aluminosilicate having a high degree of crystallinity is obtained. The range of 0.001 to 30% is preferable because the aluminum source supported on the surface layer portion of the inert carrier is difficult to diffuse inside.

  In the present invention, the method for supporting the structure-directing agent on the inert carrier is not particularly limited, but a conventionally known method for supporting a substance on the inert carrier or the like, for example, impregnation method, deposition method, ion exchange, etc. Laws are used. The amount of impregnation or loading of the structure-directing agent is in the range of 0 to 100% with respect to the weight of the inert carrier.

In the present invention, the method for supporting the silicon source on the inert carrier is not particularly limited, but a conventionally known method for supporting a substance on the inert carrier or the like, for example, an impregnation method, a deposition method, an ion exchange method, or the like. Etc. are used. The impregnation amount or loading amount of the silicon source is in the range of 0 to 100% as SiO _{2 with} respect to the weight of the inert carrier. When using silica whose silicon source is an inert carrier, it is not necessary to newly carry a silicon source.

  In the present invention, the method for supporting the aluminum source on the inert carrier is not particularly limited. For example, the aluminum source is dissolved in a solvent, heated, and impregnated or supported with the alkali metal shown above. An inert carrier is added instantaneously and stirred with heating. The solvent may be any solvent as long as the aluminum source is dissolved. For example, water, ethanol or the like can be used. The amount of the solvent is not particularly limited. For example, since the aluminum source supported on the surface layer of the inert carrier is difficult to diffuse inside, the amount of the solvent is preferably more than the pore volume of the inert carrier. More preferably, the amount is 1 to 5 times the pore volume. The heating temperature of the solution in which the aluminum source is dissolved is not particularly limited. For example, the aluminum source supported on the surface layer of the inert carrier is less likely to diffuse inside, and therefore preferably 30 to 100 ° C., More preferably, it is 60-95 degreeC. The heating and stirring temperature is not particularly limited, but is preferably 30 to 100 ° C., more preferably 60 to 95, for example, because the aluminum source supported on the surface layer portion of the inert carrier is difficult to diffuse inside. ° C. The heating and stirring time is not particularly limited, but is preferably 1 minute to 10 hours, more preferably 5 minutes to 5 hours, for example, because the aluminum source supported on the surface portion of the inert carrier is difficult to diffuse inside. It is. The ratio between the alkali metal supported on the inert carrier and the aluminum source is not particularly limited. For example, the aluminum source supported on the surface layer of the inert carrier is less likely to diffuse inside, and the crystallinity is low. Since a high aluminosilicate can be obtained, the alkali metal / aluminum source ratio (atomic ratio) is preferably 1 to 100, more preferably 3 to 50. After loading, the solvent is removed by operations such as decantation, filtration, heating or heating under reduced pressure.

  In the method of the present invention, the support of the aluminum source on the inert carrier is preferably supported at a position of 1 to 1000 μm, more preferably 1 to 500 μm from the outer surface of the inert carrier.

  In the present invention, the method for crystallizing the supported silicon source and aluminum source is not particularly limited. For example, the method can be crystallized by bringing it into contact with water vapor or, if necessary, water vapor containing a structure-directing agent. preferable. The temperature of the water vapor is not particularly limited, but it is sufficient that a crystalline porous aluminosilicate is produced, and an aluminosilicate having a high degree of crystallinity can be obtained. Therefore, the temperature is preferably 80 to 260 ° C., more preferably It is the range of 100-230 degreeC. Although the contact time with water vapor | steam is not restrict | limited in particular, Since an aluminosilicate with high crystallinity can be obtained, Preferably it is 2 hours or more, More preferably, it is the range of 2 hours-80 days.

  The method of contacting with water vapor and the apparatus thereof are not particularly limited as long as crystalline porous aluminosilicate is produced. For example, a silicon source, an aluminum source, and an alkali metal are supported in the air of a pressure vessel. It can be manufactured by installing an inert carrier, adding water to the lower part of the container, sealing, and then heating in a thermostat. The amount of water to be added is not particularly limited, but is preferably 0.1% or more based on the weight of the inert carrier because an aluminosilicate having a high degree of crystallinity can be obtained. The amount of the structure-directing agent to be added is not particularly limited, and may be 0% or more with respect to the weight of the inert carrier.

  The structure obtained in the present invention may be washed with water, dried, and fired and ion exchanged as necessary.

  The structure of the present invention can be used as a catalyst in a system that reacts with a solid acid catalyst. For example, catalytic cracking reaction of light oil and heavy oil; hydrocracking reaction of heavy oil; cyclohexane dehydrogenation, cyclopentene isomerization dehydrogenation, paraffin cyclization dehydrogenation, paraffin isomerization, paraffin hydrogenation Catalytic reforming of heavy fractions of petroleum naphtha such as cracking; isomerization of alkanes and alkenes such as butane, pentane, hexane, butene, pentene, hexene; methane, ethane, propane, butane, pentane, hexane, ethylene , Propylene, butene, pentene, hexene, etc .; benzene, alkylbenzene, naphthalene, phenol, thiophene, pyridine, etc. and ethylene, propylene, butene, pentene, hexene, methanol, ethanol, propanol, butanol, ethyl chloride, propyl Prolide, butyl chloride, etc. Aromatic alkylation reactions such as fins, alcohol alkyl halides; toluene, ethylbenzene, propylbenzene, butylbenzene, xylene, diethylbenzene, dipropylbenzene, dibutylbenzene, trimethylbenzene, triethylbenzene, tripropylbenzene, tributylbenzene, etc. It can be used for reactions such as isomerization, disproportionation, transalkylation, dealkylation reaction of alkyl aromatics; olefin polymerization reaction such as ethylene, propylene, butene, pentene, hexene.

  The structure of the present invention can also be used as a catalyst support, for example, one group element such as lithium, sodium, potassium, rubidium and cesium; two groups such as beryllium, magnesium, calcium, strontium and barium. Elements; 3 group elements such as scandium, yttrium, lanthanoid and actinoid; 4 group elements such as titanium and zirconium; 5 group elements such as vanadium, niobium and tantalum; 6 group elements such as chromium, molybdenum and tungsten; manganese, rhenium and the like 7 group elements; 8 group elements such as iron, ruthenium and osmium; 9 group elements such as cobalt, rhodium and iridium; 10 group elements such as nickel, palladium and platinum; 11 group elements such as copper, silver and gold; , 12 group elements such as cadmium; boron, aluminum, gallium, indium, It can be used as a catalyst by supporting one or more elements such as 13 group elements such as lithium; 14 group elements such as germanium, tin and lead; 15 group elements such as antimony and bismuth, and 16 group elements such as sulfur and tellurium. .

  The structure of the present invention has a crystalline porous aluminosilicate that is effective as a solid acid catalyst in the surface layer of the structure, so that the residence time of the reaction raw materials and reaction products in the structure is short, and the selectivity of the target product In addition, since it is difficult to cause poisoning of active sites and clogging of pores, the catalytic activity is unlikely to be lowered and the catalyst life is long.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples.

The measurement methods used in the following examples are shown.
(Confirmation of crystal state of structure)
The crystal state of the obtained structure was measured at a voltage of 40 kV and a current of 200 mA using a powder X-ray diffraction measurement apparatus (XRD) (manufactured by Mac Science, trade name: M18XHF).
(Measurement of aluminum depth distribution and silicon / aluminum ratio)
A sample obtained by embedding the obtained structure in a resin and cutting with an ultramicrotome was measured using a X-ray microanalyzer (EPMA) (trade name EPM-810, manufactured by Shimadzu Corporation) at a voltage of 20 kV and a current of 10 nA. Line analysis and surface analysis in the depth direction of the particle cross section were performed, and the loading ratio was calculated from the strength ratio.
(Confirmation of aluminum in zeolite framework structure)
²⁷ Measured with Al solid NMR (trade name GSX-270, manufactured by JEOL Ltd.), a peak measured in the range of chemical shift (σ) = 50 to 70 ppm attributed to 4-coordinated aluminum in the zeolite framework structure; This was confirmed by a peak measured in the range of chemical shift (σ) = 0 to 10 ppm attributed to off-lattice 6-coordinated aluminum deviating from the skeletal structure.

Example 1
To 12 ml of water, 0.3 g of sodium hydroxide (sodium / silicon ratio = 0.04 (atomic ratio)) and 1.0 g of pyrrolidine (pyrrolidine / silicon ratio = 0.07 (molar ratio)) were added and dissolved. To this aqueous solution, 11 g of silica beads (Fuji Silysia Chemical "Caractect Q-50", particle shape: spherical, particle diameter: 1.7 to 4.0 mm, surface area: 80 m ² / g, average pore diameter of 50 nm) is added. Then, silica beads were impregnated with an aqueous solution.

  Next, 0.4 g of aluminum nitrate nonahydrate (sodium / aluminum = 6.7 (atomic ratio)) was dissolved in 12 ml of water, heated to 75 ° C., and impregnated with sodium hydroxide and pyrrolidine. The added silica beads were added and stirred for 30 minutes. After stirring, the mixture was dried under reduced pressure, and dried for 5 hours at 80 ° C. in a nitrogen atmosphere.

  As a result of an aluminum line analysis of the obtained structural body, it was found that the supported aluminum was present within 80 μm from the outer surface of the silica beads.

  Put 0.8 g of water and 1.0 g of pyrrolidine into a Teflon (registered trademark) pressure vessel, raise a Teflon (registered trademark) dish so that it does not touch the aqueous solution, and carry sodium hydroxide, pyrrolidine and aluminum sources on it. 11 g of the silica beads were added, the pressure vessel was sealed, and the pressure vessel was heated at 179 ° C. for 7 days.

  Then, after washing with distilled water, drying was performed at 110 ° C. overnight, followed by firing at 540 ° C. in air.

  As a result of the powder X-ray diffraction measurement of the obtained structure (Table 1), a diffraction pattern of the MTT structure was shown in addition to the broad pattern of silica beads as the silicon source. Further, from the results of surface analysis and line analysis of aluminum (FIGS. 5 and 6), aluminum is present within 80 μm from the outer surface of the obtained structure, and the structure obtained as a result of component analysis of the local portion by EPMA. The aluminum / silicon ratio (atomic ratio) of the surface layer portion of the body was 0.008. From the outer surface of the structure, about 250 μm, and from the center, aluminum was below the detection limit.

As a result of solid-state NMR measurement of ²⁷ Al, a peak was confirmed in the range of chemical shift (σ) of 50 to 70 ppm, and it was found that aluminum was present in the zeolite framework structure.

Sectional view of the spherical structure of the present invention Sectional view of the cylindrical structure of the present invention Sectional view of the hollow cylindrical structure of the present invention Sectional view of the plate-like structure of the present invention Results of aluminum surface analysis of the structure of Example 1 Results of aluminum line analysis of the structure of Example 1

Explanation of symbols

1 Crystalline porous aluminosilicate 2 Inactive carrier

Claims (6)

A structure characterized in that a crystalline porous aluminosilicate having an MTT-type crystal structure is present in a surface layer portion of the structure, and an inert carrier is present inside the surface layer portion excluding the structure surface layer portion. The structure according to claim 1, wherein the inert carrier is silica, alumina, titania or zirconia . The structure according to claim 1 or 2, wherein the crystalline porous aluminosilicate is present in a surface layer portion from the outer surface of the structure to a depth of 1 to 1000 µm . The structure according to any one of claims 1 to 3, wherein the structure is spherical . The inert carrier is silica, and after impregnating or carrying an alkali metal and an organic amine compound as a structure directing agent on the inert carrier, the aluminum carrier and the silicon source are carried on the inert carrier, and then the crystallization treatment is performed. The method for producing a structure according to claim 1, wherein the method is performed . 6. The method for producing a structure according to claim 5, wherein the aluminum source is supported on the surface layer part from the outer surface of the inert carrier to a depth of 1 to 1000 [mu] m .

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