A method of forming a molecular separation device is provided. The method comprises growing or depositing a silica MFI zeolite coating on a ceramic support. The method further comprises growing a ZIF-8 coating on the silica MFI zeolite coating. Growing the ZIF-8 coating on the silica MFI zeolite comprises applying a first reactant fluid including a metal salt and a second reactant fluid including an imidazole reactant to the silica MFI zeolite coating. Growing the ZIF-8 coating on the silica MFI zeolite further comprises reacting the first and second reactant fluid with the silica MFI zeolite coating to produce the ZIF-8 coating. In certain implementations, at least a portion of the ZIF-8 coating is interspersed with a portion of the silica MFI coating. A molecular separation device including the ZIF-8 coating and the silica MFI zeolite is also disclosed.

The present invention aims at providing a method for producing a high-concentration alcohol from a water-alcohol mixture, in which the overall process is efficient and the present invention relates to a production method of a high-concentration alcohol, including a water adsorption step of adsorbing water of a water-alcohol mixture on an adsorption column to obtain a first concentrated alcohol, a water desorption step of introducing an alcohol to obtain a hydrous alcohol, and a membrane separation step of introducing the hydrous alcohol into a membrane separation unit provided with a membrane composite containing zeolite having an SiO.sub.2/Al.sub.2O.sub.3 molar ratio of 5 to 15 to obtain a second concentrated alcohol.

Provided is a method of producing piperylene from a hydrocarbon mixture derived from a petroleum fraction having a carbon number of 5. The hydrocarbon mixture has a piperylene proportional content of not less than 60 mass % and not more than 80 mass % and has a cyclic hydrocarbon proportional content of not less than 20 mass % and not more than 40 mass %. The method of producing piperylene includes a membrane separation step of performing membrane separation of the hydrocarbon mixture using a zeolite membrane to obtain a separated product in which piperylene is enriched.

A DDR-type zeolite seed crystal has an average particle diameter of less than or equal to 0.2 μm, and an average aspect ratio of less than or equal to 1.3.

Provided is a method for separating ammonia gas using zeolite membrane having excellent separation stability at a high temperature capable of separating ammonia gas from a mixed gas composed of multiple components including ammonia gas, hydrogen gas, and nitrogen gas to the permeation side with high selectivity and high permeability. Also provided is a method for separating ammonia by selectively permeating ammonia gas from a mixed gas containing at least ammonia gas, hydrogen gas, and nitrogen gas using a zeolite membrane, wherein the ammonia gas concentration in the mixed gas is 1.0% by volume or more.

Provided are an all-silica zeolite separation membrane for separating carbon dioxide, etc., and not causing a decrease in the processing amount due to adsorption of water molecules, and a production method therefor. One aspect of the present invention is a zeolite separation membrane, in which the framework of a zeolite crystal structure formed on a porous support is all silica, characterized in that the zeolite crystal structure formed on the porous support is fluorine free. Another aspect of the present invention is a method for producing a zeolite separation membrane having a zeolite crystal structure on a porous support, characterized in that the method includes a step of producing a seed crystal, a step of applying the seed crystal onto the porous support, a step of producing a membrane synthesis raw material composition, and a step of immersing the porous support having the seed crystal applied thereon in the membrane synthesis raw material composition and performing hydrothermal synthesis, and the membrane synthesis raw material composition contains a silica source and an organic template and does not contain a fluorine compound.

A process for producing a zeolite membrane composite includes a step of obtaining FAU-type seed crystals, a step of depositing the FAU-type seed crystals on a support, a step of forming an AFX-type zeolite membrane on the support by immersing the support in a raw material solution and growing an AFX-type zeolite from the FAU-type seed crystals by hydrothermal synthesis, and a step of removing a structure-directing agent from the AFX-type zeolite membrane. In this way, the AFX-type zeolite membrane can be provided.

The present disclosure relates to a semipermeable membrane for water treatment, including a photoactive layer. The photoactive layer includes a plurality of one-dimensional nano structure bundles and the one-dimensional nano structure is nano-structured so that a surface of the semipermeable membrane for water treatment has a hydrophobicity.

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.

A super-hydrophilic membrane comprising a metal mesh comprising copper and a coating comprising copper(I) iodide crystals and a method of preparation thereof are disclosed. The membranes provided by the invention have improved physical properties, such as super-hydrophilicity as well as underwater oleophobicity, and are specifically adapted for oil/water separation processes.