Abstract: In an RHO-type zeolite, in a case where a peak at a lattice spacing of 9.96 to 11.25 ? in a measurement using a powder X-ray diffraction method is assumed as a reference peak and an intensity of the reference peak is assumed as 100, a relative intensity of a peak at a lattice spacing of 4.59 to 4.85 ? is 150 to 300, a relative intensity of a peak at a lattice spacing of 3.55 to 3.64 ? is 200 to 500, and a relative intensity of a peak at a lattice spacing of 2.98 to 3.06 ? is 100 to 200.

Abstract: A zeolite membrane complex comprises: a support; and a zeolite membrane formed on the support. The membrane is of SAT-type zeolite, and in an X-ray diffraction pattern obtained by X-ray irradiation to the zeolite membrane, a peak intensity around 2?=13.9° is 1.5 times or more a peak intensity around 2?=8.5°.

Abstract: Seed crystals are crystals of zeolite to be attached onto a support in production of a zeolite membrane complex including the support and a zeolite membrane formed on the support. The specific surface area of the seed crystals is not smaller than 10 m2/g and not larger than 150 m2/g. The strength obtained from a crystal component at a diffraction angle 2? indicating a maximum peak in a range of diffraction angle 2? from 12° to 25° in an X-ray diffraction pattern obtained by emitting X-ray to the seed crystals is not less than once and not more than 30 times that obtained from an amorphous component. It is thereby possible to improve adherence of the seed crystals to the support.

Abstract: A zeolite membrane complex includes a support and a zeolite membrane formed on the support. The zeolite membrane is of an SAT-type zeolite. Among particles on the surface of the zeolite membrane, particles that have aspect ratios higher than or equal to 1.2 and lower than or equal to 10 account for 85% or more of the area of the surface of the zeolite membrane. This improves the orientations of the particles and also reduces the interstices among the particles. As a result, the denseness of the zeolite membrane is improved. Accordingly, for example, high gas separation performance can be obtained when the zeolite membrane complex is used as a gas separation membrane.

Abstract: A zeolite membrane complex includes a porous support and a zeolite membrane formed on the support. The zeolite membrane contains Al, P, and a tetravalent element. The composition of the zeolite membrane measured by X-ray photoelectron spectroscopy is such that the molar ratio of the tetravalent element to Al is higher than or equal to 0.01 and lower than or equal to 0.5, the molar ratio of P to Al is higher than or equal to 0.5 and lower than 1.0, and the total molar ratio of P and the tetravalent element to Al is higher than or equal to 0.9 and lower than or equal to 1.3. The zeolite membrane contains a zeolite crystal with an accessible volume higher than or equal to 450 ?3.

Abstract: A peak intensity of a (002) plane is greater than or equal to 0.5 times a peak intensity of a (100) plane in an X-ray diffraction pattern obtained by irradiation of X-rays to a membrane surface of the ERI membrane.

Abstract: A zeolite membrane complex includes a porous support and a zeolite membrane formed on the support. Water molecules are adsorbed in the zeolite membrane. A decreasing rate of water content in the zeolite membrane from 250° C. to 500° C. is 0.1% or more.

Abstract: A seed crystal is a crystal of zeolite that is to be deposited on a support when producing a zeolite membrane complex that includes the support and a zeolite membrane formed on the support. A volume-cumulative particle size distribution of the seed crystal, measured by a laser diffraction scattering method, has a coefficient of variation of 0.5 or less and a kurtosis of 5 or less. Use of these seed crystals improves the bonding of zeolite crystals when producing the zeolite membrane. As a result, a dense zeolite membrane can be formed.

Abstract: Part of a zeolite membrane of a zeolite membrane complex is set in pores of a support over a boundary surface between the zeolite membrane and the support. With respect to a main element constituting the zeolite membrane, a distance in a depth direction perpendicular to the boundary surface between a position at which a ratio (B/C)/A is 0.8 and the boundary surface is preferably not smaller than 0.01 ?m and not larger than 5 ?m. B/C is a value obtained by dividing an atomic percentage B of the main element inside the support by a porosity C of the support. The ratio (B/C)/A is a ratio of the value to an atomic percentage A of the main element in the zeolite membrane.

Abstract: A peak intensity of a (110) plane is greater than or equal to 2.5 times a peak intensity of a (004) plane in an X-ray diffraction pattern obtained by irradiation of X-rays to a membrane surface of the AFX membrane.

Abstract: A zeolite membrane complex includes a support and a zeolite membrane formed on the support. The zeolite membrane is of an SAT-type zeolite. Among particles on the surface of the zeolite membrane, particles that have aspect ratios higher than or equal to 1.2 and lower than or equal to 10 account for 85% or more of the area of the surface of the zeolite membrane. This improves the orientations of the particles and also reduces the interstices among the particles. As a result, the denseness of the zeolite membrane is improved. Accordingly, for example, high gas separation performance can be obtained when the zeolite membrane complex is used as a gas separation membrane.

Abstract: A seed crystal is a crystal of zeolite that is to be deposited on a support when producing a zeolite membrane complex that includes the support and a zeolite membrane formed on the support. A volume-cumulative particle size distribution of the seed crystal, measured by a laser diffraction scattering method, has a coefficient of variation of 0.5 or less and a kurtosis of 5 or less. Use of these seed crystals improves the bonding of zeolite crystals when producing the zeolite membrane. As a result, a dense zeolite membrane can be formed.

Abstract: The monolithic base is a porous alumina body that includes pores and that is configured by alumina particles as an aggregate and an oxide phase as a binding material. The alumina particles include microscopic alumina particles having a particle diameter of greater than or equal to 0.5 ?m and less than or equal to 5 ?m and coarse alumina particles having a particle diameter of greater than 5 ?m. The number of microscopic alumina particles that are encapsulated in the oxide phase is greater than or equal to 50% of the total number of microscopic alumina particles and coarse alumina particles.

Abstract: A zeolite membrane complex comprises: a support; and a zeolite membrane formed on the support. The membrane is of SAT-type zeolite, and in an X-ray diffraction pattern obtained by X-ray irradiation to the zeolite membrane, a peak intensity around 2?=13.9° is 1.5 times or more a peak intensity around 2?=8.5°.

Abstract: A peak intensity of a (110) plane is greater than or equal to 2.5 times a peak intensity of a (004) plane in an X-ray diffraction pattern obtained by irradiation of X-rays to a membrane surface of the AFX membrane.

Abstract: A peak intensity of a (002) plane is greater than or equal to 0.5 times a peak intensity of a (100) plane in an X-ray diffraction pattern obtained by irradiation of X-rays to a membrane surface of the ERI membrane.

Abstract: Seed crystals are crystals of zeolite to be attached onto a support in production of a zeolite membrane complex including the support and a zeolite membrane formed on the support. The specific surface area of the seed crystals is not smaller than 10 m2/g and not larger than 150 m2/g. The strength obtained from a crystal component at a diffraction angle 2? indicating a maximum peak in a range of diffraction angle 2? from 12° to 25° in an X-ray diffraction pattern obtained by emitting X-ray to the seed crystals is not less than once and not more than 30 times that obtained from an amorphous component. It is thereby possible to improve adherence of the seed crystals to the support.

Abstract: The monolithic base is a porous alumina body that includes pores and that is configured by alumina particles as an aggregate and an oxide phase as a binding material. The alumina particles include microscopic alumina particles having a particle diameter of greater than or equal to 0.5 ?m and less than or equal to 5 ?m and coarse alumina particles having a particle diameter of greater than 5 ?m. The number of microscopic alumina particles that are encapsulated in the oxide phase is greater than or equal to 50% of the total number of microscopic alumina particles and coarse alumina particles.