Abstract: A method for manufacturing a zeolite membrane structure includes a step of forming a first zeolite membrane on a porous support by hydrothermal synthesis in a state in which the porous support is immersed in a first zeolite membrane formation solution, a step of immersing the porous support formed the first zeolite membrane for greater than or equal to 5 minutes in a second zeolite membrane formation solution at greater than or equal to 10 degrees C. and less than or equal to 70 degrees C. and greater than or equal to pH 10, and a step of forming a second zeolite membrane on the first zeolite membrane by hydrothermal synthesis in a state in which the porous support formed the first zeolite membrane is immersed in the second zeolite membrane formation solution. The first zeolite membrane and the second zeolite membrane share at least one composite building unit constituting a framework structure.

Abstract: A dehydration method is a dehydration method for selectively separating water from a mixture that contains water, using a zeolite membrane having an AFX structure, and the method includes a step of supplying the mixture to a supply side space of the zeolite membrane having an AFX structure, and a step of making a pressure difference between the supply side space and a permeation side space of the zeolite membrane having an AFX structure.

Abstract: A dehydration method is a dehydration method for selectively separating water from a mixture that contains water, and the method includes a step of supplying the mixture to a supply side space of a zeolite membrane having an ERI structure, and a step of making a pressure difference between the supply side space and a permeation side space of the zeolite membrane having an ERI structure.

Abstract: The gas separation method is executed under a condition in which a partial pressure of a first gas (G1) in a feed gas that contains at least mutually different gases being the first gas (G1), a second gas (G2) and a third gas (G3) becomes less than or equal to the total pressure of a permeate-side space (S2) of a gas separation membrane (30). The gas separation method includes a step of causing flow of a sweep gas that contains at least the third gas (G3) into the permeate-side space (S2) of the gas separation membrane (30) while supplying a feed gas to a feed-side space (S1) of the gas separation membrane (30). The permeation rate of the first gas (G1) in the gas separation membrane (30) is greater than the permeation rate of the second gas (G2).

Abstract: A production method for zeolite powder containing forming zeolite seed crystals by wet pulverizing zeolite crystals using a silica unsaturated alkali solution containing an alkali source, preparing a silica saturated alkali solution by adding a silica source to the silica unsaturated alkali solution containing the zeolite seed crystals, and synthesizing zeolite powder by hermetically heating the silica saturated alkali solution.

Abstract: A production method for zeolite powder includes disintegrating zeolite seed crystals in a silica unsaturated alkali solution containing an alkali source, preparing a silica saturated alkali solution by adding a silica source to the silica unsaturated alkali solution containing the zeolite seed crystals, and synthesizing zeolite powder by hermetically heating the silica saturated alkali solution.

Abstract: A zeolite crystal has an AFX structure and a hexagonal plate shape. Ratio of a maximum Feret diameter (L1) in a plan view with respect to a plate thickness in a side view is greater than or equal to 2.

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 (004) plane is greater than or equal to 3 times a peak intensity of a (110) plane in an X-ray diffraction pattern obtained by irradiation of X-rays to a membrane surface of an AFX membrane.

Abstract: A method of synthesis for an aluminophosphate-based zeolite membrane includes a steps of preparing a mixed solution with a pH greater than or equal to 6 and less than or equal to 9 by mixing an acidic phosphorous source with an alkali source, a steps of preparing a starting material solution by adding and mixing an aluminum source to the prepared mixed solution, and a steps of synthesizing an aluminophosphate-based zeolite membrane by hydrothermally synthesizing the starting material solution.

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 method for inspecting a separation membrane module has a sealing step for sealing a gas for inspection on a primary side of zeolite membrane. The dynamic molecular diameter for the gas for inspection is greater than 1.07 times the pore diameter in the zeolite membrane. The gas for inspection has the characteristic of having a rate of reduction for a CO2 gas permeation rate in the zeolite membrane of less than 10% when a separation membrane structure is allowed to stand for 60 minutes in the gas for inspection at 25 degrees C. and 0.1 MPaG.

Abstract: A method for inspecting a separation membrane structure includes an assembly step of sealing a separation membrane structure that includes a porous substrate and a separation membrane into a casing, and an inspection step of applying pressure to an inspection liquid that has filled a first main surface side of the separation membrane.

Abstract: A separation membrane structure includes a porous support, a first separation membrane and a second separation membrane. The first separation membrane is formed on the porous support and contains high silica zeolite having Si/Al atomic ratio of greater than or equal to 200. The second separation membrane is formed on the first separation membrane and contains cation.

Abstract: A drying method for a separation membrane includes supplying a gas for drying to the separation membrane so that a value obtained by dividing the difference between a maximum value and a minimum value of a flow rate of the gas for drying on a membrane surface of the separation membrane by the minimum value of the flow rate is less than or equal to 15%. The gas for drying is less than or equal to 40 degree C. and contains a water-soluble gas that has a solubility in 1 cm3 of water of greater than or equal to 0.5 cm3 in conditions of 40 degree C. and 1 atmosphere.

Abstract: Provided is a zeolite membrane manufactured by: subjecting a porous body to heat treatment at 400° C. or more in the presence of oxygen as pretreatment, before adhering zeolite seed crystals to a surface of the porous body; storing the porous body under an environment of humidity of 30% or more for 12 hours or more after the heat treatment; and subsequently adhering the zeolite seed crystals to the porous body. The zeolite membrane having oxygen eight-membered rings, which is manufactured by subjecting the porous body to the heat treatment, provides a value that is obtained by dividing a permeance of CF4 by a permeance of CO2 to be 0.015 or less, and has fewer defects.

Abstract: A production method for zeolite powder includes disintegrating zeolite seed crystals in a silica unsaturated alkali solution containing an alkali source, preparing a silica saturated alkali solution by adding a silica source to the silica unsaturated alkali solution containing the zeolite seed crystals, and synthesizing zeolite powder by hermetically heating the silica saturated alkali solution.

Abstract: A production method for zeolite powder containing forming zeolite seed crystals by wet pulverizing zeolite crystals using a silica unsaturated alkali solution containing an alkali source, preparing a silica saturated alkali solution by adding a silica source to the silica unsaturated alkali solution containing the zeolite seed crystals, and synthesizing zeolite powder by hermetically heating the silica saturated alkali solution.

Abstract: Provided is a method for producing a DDR type zeolite crystal, the method including: a raw material solution preparing step of preparing a raw material solution by mixing at least silica, water, an organic solvent, and 1-adamantanamine that is a structure directing agent; and a DDR type zeolite crystal generating step of generating a DDR type zeolite crystal by performing a heating treatment on the raw material solution, in which the organic solvent is an organic solvent containing no amine, and the raw material solution is a raw material solution containing no PRTR substance.

Abstract: A repair method for a separation membrane including a step of applying a colloidal solution to a surface of a separation membrane formed on a support. The colloidal solution has a predetermined pH. In colloidal solution, repair material particles are dispersed in an aqueous solvent. The repair material particles have an electrical charge that is opposite to an electrical charge of the support at the predetermined pH.