Abstract: To provide an Fe(II)-substituted beta type zeolite which has been ion-exchanged with Fe(II) ions and can effectively adsorb and remove nitrogen monoxide or hydrocarbon contained in gas to be cleaned, even if oxygen is present in the gas at a high concentration or the temperature of the gas is low. In the Fe(II)-substituted beta type zeolite, a ratio of SiO2/Al2O3 is preferably 10 to 18, a BET specific surface area is preferably 400 m2/g to 700 m2/g, a micropore specific surface area is preferably 290 m2/g to 500 m2/g, and a micropore volume is preferably 0.15 cm3/g to 0.25 cm3/g. The amount of Fe(II) supported is preferably 0.01% by mass to 6.5% by mass based on the Fe(II)-substituted beta type zeolite.

Abstract: Provided is a method for producing an MTW-type zeolite. The reaction mixture contains a silica source, an alumina source, an alkali source, and water is reacted with a seed crystal of a zeolite to produce an MTW-type zeolite. The reaction mixture has a composition, which makes a synthesized zeolite contain an MFI-type zeolite when the zeolite is synthesized solely from the reaction mixture, is used. As the seed crystal, a beta-type zeolite which has a ratio of SiO2/Al2O3 of 8 to 50 and does not contain a structure direction agent is used. The seed crystal is added to the reaction mixture, in a proportion of 0.1% by mass to 20% by mass based on a silica component in the reaction mixture. The reaction mixture to which the seed crystal has been added is heated at 100° C. to 200° C. in a sealed state.

Abstract: The method for producing an MTW-type zeolite according to the present invention includes: mixing a silica source, an alumina source, an alkali source, a lithium source, and water so as to obtain a reaction mixture having a composition represented by specific molar ratios; (2) adding an MTW-type zeolite which has a SiO2/Al2O3 ratio of 10 to 500 and does not contain an organic compound, as a seed crystal, to the reaction mixture in a proportion of 0.1 to 20% by weight relative to the silica component in the reaction mixture; and (3) airtightly heating the reaction mixture, to which the seed crystal has been added, at 100 to 200° C.

Abstract: Disclosed is a method for readily and inexpensively producing zeolite without using an organic structure-directing agent (organic SDA). Specifically disclosed is a method whereby a gel containing a silica source, an alumina source, an alkaline source and water is reacted with zeolite seed crystals, to produce a zeolite with the same kind of skeletal structure as the zeolite. The gel used is a gel of a composition whereby, when a zeolite is synthesized from this gel only, the synthesized zeolite comprises at least one of the kinds of composite building units of the target zeolite.

Abstract: A zeolite beta according to the present invention has a SiO2/Al2O3 ratio of 10 to 16 and is aluminum-rich. The zeolite beta has a BET specific surface area measured in the state of a sodium type of 500 to 700 m2/g, a micropore specific surface area of 350 to 500 m2/g, and a micropore volume of 0.15 to 0.25 cm3/g.

Abstract: A zeolite beta according to the present invention has a SiO2/Al2O3 ratio of 10 to 16 and is aluminum-rich. The zeolite beta has a BET specific surface area measured in the state of a sodium type of 500 to 700 m2/g, a micropore specific surface area of 350 to 500 m2/g, and a micropore volume of 0.15 to 0.25 cm3/g.

Abstract: An adsorbent comprising zeolite exhibiting a moisture adsorption of at least 28 wt. % at 25° C. under a partial pressure of water vapor of 5 Torr, and exhibiting a moisture adsorption difference of 15-25 wt. % between a moisture adsorption at 25° C. under a partial pressure of water vapor of 5 Torr and a moisture adsorption at 100° C. under a partial pressure of water vapor of 15 Torr. This adsorbent is produced by ion-exchanging an exchangeable cation in a zeolite, and then, heat-treating the cation-exchanged zeolite in an air or nitrogen stream, or with steam. The adsorbent exhibits a large moisture adsorption at ordinary temperature under a relatively low partial pressure of water vapor and a small moisture adsorption at a relatively low regeneration temperature, and thus, has an enhanced effective moisture adsorption, and is used for a zeolite-water heat pump system and an open cycle moisture adsorption-desorption system.

Abstract: A method for adsorbing and removing ethylene in an exhaust gas, comprises contacting with the gas an adsorbent comprising a zeolite which contains Ag and which has a ferrierite structure with a SiO2/Al2O3 molar ratio being at least 15.

Abstract: A method for purifying an exhaust gas by contacting the exhaust gas with an exhaust gas-purifying catalyst comprising a nitrogen oxide-removing catalyst and an adsorbent for ethylene comprising a zeolite which contains Ag, and also Pd, optionally which has a ferrierite structure.

Abstract: An adsorbent for ethylene, comprising a zeolite which contains Ag and which has a ferrierite structure with a SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio being at least 15.

Abstract: The subject of the invention is to provide a new high-performance flame retardant having excellent flame resistant effect and smoke-suppressing effect and generating no hazardous gas, and a new flame retardant resin-composition used it. As a means for solution, a flame retardant comprising ethylenediamine-containing zinc phosphate and other phosphorus-containing compound is formulated in amounts of 10 to 200 parts by weight to 100 parts by weight of resin.

Abstract: A crystalline zeolite X adsorbent comprising a crystalline zeolite X having an SiO.sub.2 /A.sub.2 O.sub.3 molar ratio of not larger than 3.0, where lithium cations associated with an AlO.sub.2 tetrahedron unit are 80 to less than 88 mol % of the total cations and the content of alkaline earth metal cations is from 0.5 to less than 4.6 mo % is produced by ion-exchanging with lithium cations at least 90 mol % of the cations associated with an Al.sub.2 O.sub.3 tetrahedron unit of a crystalline zeolite X having an SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio of not larger than 3.0, ion-exchanging the crystalline zeolite X again with an aqueous solution of mixed salts of an alkali metal salt and an alkaline earth metal salt to decrease the lithium cations associated with the AlO.sub.2 tetrahedron unit to 80 to less than 88 mol %, followed by washing and drying, and activating the crystalline zeolite X.

Abstract: A synthetic mordenite molded body is prepared by a process wherein a starting mixture comprising, as the main components, a silica source, an alumina source, an alkali source and water is molded into a starting molded body, the molded body is calcined and the calcined molded body is heated in an aqueous solution of sodium silicate. The starting mixture has incorporated therein a mordenite seed crystal powder. When the molded body is calcined, the temperature is elevated by heating to a calcination temperature not lower than 400.degree. C. at an average rate of at least 10.degree. C./min and calcination is conducted at the calcination temperature within a time period of 2 hours. When the calcined molded body is crystallized, an aqueous solution of sodium silicate having an SiO.sub.2 concentration of 7 to 25% by weight, an Na.sub.2 O concentration of 2 to 8% by weight and an SiO.sub.2 /Na.sub.2 O molar ratio of from 0.9 to 4.0 is used as the aqueous solution of sodium silicate.

Abstract: Disclosed is a zeolite having a composition of the following formula: xM.sub.2/n O.Al.sub.2 O.sub.3.(5-10)SiO.sub.2.yH.sub.2 O wherein M is at least one cation having a valency of n, and x is 0.8-2 and y is 0-10, and exhibiting an X-ray powder diffraction pattern shown in Table 1. This zeolite is prepared by a process wherein a reaction mixture comprising a silica source, an alumina source, an alkali source, a potassium source and water and having a composition satisfying the following molar ratios: SiO.sub.2 /Al.sub.2 O.sub.3 =6-40, OH/SiO.sub.2 =0.3-1, K.sub.2 O/M.sub.2 O=0.1-0.9 (M: the total of alkali metals), and H.sub.2 O/SiO.sub.2 =10-70, is crystallized at 120.degree. to 200.degree. C. with stirring. The zeolite is also prepared by a process wherein a granular amorphous aluminosilicate containing aluminum in an amount of 4 to 22 wt. % as Al.sub.2 O.sub.

Abstract: A mordenite type zeolite having a high purity and a high SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio is prepared without using an organic or inorganic mineralizer, by a process wherein a homogeneous aluminosilicate containing 3 to 14% by weight, expressed in terms of Al.sub.2 O.sub.3 (calculated as the anhydride), of aluminum is crystallized in an aqueous solution of an alkali metal hydroxide.

Abstract: A ferrierite type zeolite having a high purity and a high SiO.sub.2 /Al.sub.2 O.sub.3 molar ratio is prepared by reacting simultaneously and continuously an aqueous sodium and/or potassium silicate solution with an aluminum-containing solution to obtain a homogeneous phase compound of a granular amorphous aluminosilicate containing Al in an amount of 3 to 14 wt. % as calculated as anhydrous Al.sub.2 O.sub.3 and Na and/or K in an amount of 1 to 17 wt. % as calculated as anhydrous Na.sub.2 O and/or K.sub.2 O; and then, crystallizing the homogeneous phase compound in the form of a slurry in water or in an aqueous sodium hydroxide and/or potassium hydroxide solution. The molar ratio of K.sup.+ to the total of (K.sup.+ +Na.sup.+) in the slurry is 0.1 to 0.9.

Abstract: A zeolite similar to ZSM-5, having lattice spacings (d-values), shown in Table 1, of the X-ray powder diffraction pattern, and a ferrierite zeolite are prepared by crystallizing a homogeneous phase compound of a granular amorphous aluminosilicate in water or in an aqueous solution of an alkali metal hydroxide and/or an alkali metal silicate.

Abstract: An L type zeolite of a high purity is prepared by crystallizing an amorphous sodium alminosilicate compound containing a silicon component in an amount of 67 to 91 wt. % as SiO.sub.2 on the anhydrous basis in an aqueous potassium hydroxide solution.

Abstract: A zeolite encapsulating material composed of an A-type zeolite expressed by a typical unit cell (CsxMII.sub.y Naz)(AlO.sub.2.SiO.sub.2).sub.12 .multidot.(NaAlO.sub.2).delta..multidot..omega.H.sub.2 O wherein MII represents a divalent metal; O.ltoreq..delta..ltoreq.1; and .omega. represents a positive number. Further, in the above stated unit cell, x, y and z which respectively represent the numbers of Cs, M and Na within the unit cell are in a relation:x+2y+z=123.ltoreq.x<100<y.ltoreq.4.5.

Abstract: A zeolite occluding material composed of an A-type zeolite expressed by a generic formula (Kx My Naz)(AlO.sub.2.SiO.sub.2).sub.12.(NaAlO.sub.2).delta...omega.H.sub.2 O wherein M represents a bivalent metal; O.ltoreq..delta..ltoreq.1; and .omega. represents a positive number. Further, in the above stated unit cell, x, y and z which respectively represent the numbers of K, M and Na within the unit crystal lattice (or unit crystal cell) are in a relation:x+2y+z=123.ltoreq.x<101<y.ltoreq.4.5.