Provided is a method of producing a zeolite film continuously and efficiently. The method of forming zeolite on a surface of a support is characterized in that the method includes: a first step of attaching zeolite fine crystals to a surface of a support; a second step of preparing synthetic gel for growing the fine crystals; a third step of putting the support and the synthetic gel into a continuous reactor and performing hydrothermal synthesis; and a fourth step of cleaning the support on which zeolite has been hydrothermally synthesized, and in the third step, the temperature, pressure, and flow of the synthetic gel in the continuous reactor is adjusted, the support is moved being immersed in the synthetic gel, the reaction time of the hydrothermal synthesis is adjusted by adjusting the time from when the support enters the continuous reactor to when the support exits the continuous reactor.

The present disclosure provides a fluorine-based resin porous membrane exhibiting high mechanical strength and low heat shrinkage rate while having a fine pore size, and a method for preparing the same.

A metal-organic framework material separation membrane and a preparation method for the metal-organic framework material separation membrane are provided. The metal-organic framework material separation membrane has a base membrane and a metal-organic framework material functional layer. The metal-organic framework material functional layer comprises has an inter-embedded polyhedron structure. The preparation metal-organic framework material separation membrane includes the steps of: (1) preparing a solution containing a first organic solvent, an organic ligand, a metal compound, and an auxiliary agent; (2) subjecting a base membrane to a pretreatment, involving introducing, on the surface of the base membrane, metal atoms from the metal compound of step (1); and (3) mixing the pretreated base membrane of step (2) with the solution of step (1) to obtain a first mixture, and then heating the first mixture for reaction, so as to prepare a metal-organic framework material separation membrane.

The present invention relates to a method of controlling a defect structure in a chabazite (CHA) zeolite membrane, the CHA zeolite membrane having a controlled defect structure by the method and a method of separating CO.sub.2, H.sub.2, or He and water from a mixture of water and an organic solvent using the CHA zeolite membrane, and more particularly, to a method of controlling a defect structure in a CHA zeolite membrane that improves the separation performance by reducing the amount and size of defects formed in the CHA membrane structure when removing organic-structure-directing agents in the membrane through calcination at a low temperature using ozone.

The present invention relates to a method of controlling a defect structure in an MFI zeolite membrane and a method of separating xylene isomers using the MFI zeolite membrane produced by the method, and more particularly, to a method of controlling a defect structure in an MFI zeolite membrane that improves the performance of separating a xylene isomer by reducing the amount and size of defects formed in the MFI membrane structure when removing organic-structure-directing agents in the membrane through calcination at a low temperature using ozone.

The present disclosure discloses a preparation method of an organosilica/ceramic composite membrane with a gradient pore structure. The preparation method comprises: (1) selecting a porous ceramic material as a membrane support layer; (2) gradually replacing a solvent with water to prepare zirconium colloidal sols with different particle sizes, and successively coating the prepared zirconium colloidal sols onto a ceramic support from large to small so as to form a membrane transition layer with a gradient pore structure; and (3) catalytically synthesizing an organosilica polymeric sol using hydrochloric acid, coating the prepared organosilica sol onto the preheated transition layer through ultrasonic thermal spraying to undergo heat treatment, so as to prepare the organosilica/ceramic composite membrane with the gradient pore structure. According to the present disclosure, the transition layer with the gradient pore structure is prepared by using the zirconium colloidal sols with different particle sizes. An ultrathin defect-free organosilica separation layer is prepared through ultrasonic thermal spraying. As a result, the obtained organosilica/ceramic composite membrane can be applied to the fields of salt-containing dye wastewater treatment and polypeptide bioactive substance separation.

Provided is a method of producing a zeolite film continuously and efficiently.

Zeolite is formed on a surface of a support using a method including: a first step of attaching zeolite fine crystals to a surface of a support; a second step of preparing synthetic gel for growing the fine crystals; a third step of putting the support and the synthetic gel into a reactor and performing hydrothermal synthesis; and a fourth step of cleaning the support subjected to the hydrothermal synthesis, in which in the third step, multiple containers arranged to be movable in a constant-temperature apparatus are each used as the reactor, the temperature and pressure for the hydrothermal synthesis is adjusted by the temperature and pressure in the constant-temperature apparatus, and the reaction time of the hydrothermal synthesis is adjusted by setting the time from when the reactor enters the constant-temperature apparatus to when the reactor exits the constant-temperature apparatus.

Provided is a method of producing a zeolite film continuously and efficiently. The method of forming zeolite on a surface of a support is characterized in that the method includes: a first step of attaching zeolite fine crystals to a surface of a support; a second step of preparing synthetic gel for growing the fine crystals; a third step of putting the support and the synthetic gel into a continuous reactor and performing hydrothermal synthesis; and a fourth step of cleaning the support on which zeolite has been hydrothermally synthesized, and in the third step, the temperature, pressure, and flow of the synthetic gel in the continuous reactor is adjusted, the support is moved being immersed in the synthetic gel, the reaction time of the hydrothermal synthesis is adjusted by adjusting the time from when the support enters the continuous reactor to when the support exits the continuous reactor.

A preparation method of separation membrane is provided. First, a polyimide composition including a dissolvable polyimide, a crosslinking agent, and a solvent is provided. The dissolvable polyimide is represented by formula 1:

##STR00001## wherein B is a tetravalent organic group derived from a tetracarboxylic dianhydride containing aromatic group, A is a divalent organic group derived from a diamine containing aromatic group, A is a divalent organic group derived from a diamine containing aromatic group and carboxylic acid group, and 0.1X0.9. The crosslinking agent is an aziridine crosslinking agent, an isocyanate crosslinking agent, an epoxy crosslinking agent, a diamine crosslinking agent, or a triamine crosslinking agent. A crosslinking process is performed on the polyimide composition. The polyimide composition which has been subjected to the crosslinking process is coated on a substrate to form a polyimide membrane. A dry phase inversion process is performed on the polyimide membrane.

A hollow fiber membrane of the present invention is a hollow fiber membrane having an outer surface and an inner surface, wherein the inner surface has a zebra stripe pattern in which dense portions and porous portions are alternately formed in the longitudinal direction, and the outer surface has a maximum pore size of about 1 m or less (about 1 m), and wherein the hollow fiber membrane has a water permeability (flux) of about 1,300 LMH/bar to about 5,000 LMH/bar.