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.

A process for manufacturing a porous body, includes preparing a dispersion liquid having a dispersion medium with cellulose-based nanofibers that have an average fiber diameter from 1 to 100 nm and dispersed therein, attaching the dispersion liquid to a porous support having a plurality of pores that connect with one another, removing the dispersion liquid attached to a surface of the porous support excluding an inside of pores of the porous support, and subsequently drying the porous support including the dispersion liquid in the pores of the porous support to remove the dispersion medium.

In order to obtain a crosslinked cellulose without derivatization, a polymer according to an embodiment of the present disclosure is a polymer having a structure in which cellulose substantially represented by the following formula (c1) is crosslinked with a polyfunctional epoxy compound:

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wherein in the formula (c1), n represents an integer of 2 or more.

The invention relates to a high-strength hollow fiber zeolite membrane and its preparation method, characterized in that the support of the high-strength zeolite membrane has a multi-channel hollow fiber configuration. The preparation method comprises first preparing a crystal seed solution, then immersing the dry support with the multi-channel hollow fiber configuration in the crystal seed solution, and extracting and drying the support to obtain a crystal-seeded support; and finally placing the crystal-seeded support in a zeolite membrane synthetic fluid, performing hydrothermal synthesis, and taking out, washing and drying the product to obtain the high-strength hollow fiber zeolite membrane. The multi-channel hollow fiber support can provide high mechanical property, which greatly reduces the depreciation rate of the hollow fiber zeolite membrane equipment during use. Meanwhile, the multi-channel hollow fiber zeolite membrane prepared by the Invention possesses high loading density of permeation flux and membrane module and can reduce the production cost and improve the separation efficiency significantly, and thus lays the foundation for promoting the industrial application of the hollow fiber zeolite membrane.

The invention relates to macroporous, hydrophobic and isotropic polyvinylidene fluoride (PVDF) membranes having improved properties and to a new method for preparing the same

The present invention relates to high performance, crosslinked hollow-fibre membranes and a new process for manufacturing the same.

The present disclosure is directed to ultrafiltration membranes based on bacterial nanocellulose and graphene oxide. In particular, the present disclosure is directed to the novel design and incorporation of membranes for realizing new, highly efficient, and environmentally-friendly anti-biofouling membranes for water purification.

A method for increasing the thickness of a sheet of CNTs (146, 147, 246, 346), comprising: providing a wet sheet of CNTs, wherein the sheet of CNTs is either a continuous sheet of CNTs or a portion of sheet of CNTs, wherein the wet sheet of CNTs is the result of applying a process for manufacturing a sheet of CNTs; separating the wet sheet of CNTs from any filter or support element; drying the wet sheet of CNTs (146, 147, 246, 346) by applying heat (15, 25, 35) from a heat source (12, 22, 32). A method for manufacturing a continuous sheet of CNTs, comprising: in a container (41) filled with a liquid solution (42) comprising CNTs at certain concentration, submerging a vacuum tank (43) having a lower surface forming a grillage; moving an elongated filtering membrane (44) along the lower surface of the vacuum tank (43) while vacuum is applied on the elongated filtering membrane (44) in such a way that in the surface of the filtering membrane (44) opposed to the surface in contact with the lower surface of the vacuum tank (43) CNTs are deposited forming a continuous sheet of CNTs (45) of constant thickness; taking the filtering membrane (44) together with the continuous sheet of CNTs (45) out of the container (41); washing the continuous sheet of CNTs (55) disposed on the filtering membrane or on a support element (54) in a second container (51) filled with cleaning solution (52); taking the continuous sheet of CNTs (55) together with the filtering membrane or the support element (54) out of the second container (51); separating the continuous sheet of CNTs (55) from the filtering membrane or the support element (54); drying the continuous sheet of CNTs (55) by applying the method for increasing the thickness of a sheet of CNTs.

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 cm.sup.3 of water of greater than or equal to 0.5 cm.sup.3 in conditions of 40 degree C. and 1 atmosphere.

An amphiphilic block copolymer comprises a poly(phenylene ether) block or a poly(phenylene ether) copolymer block and a hydrophilic block or graft. A method of making the amphiphilic block copolymer comprises polymerization of a hydrophilic ethylenically unsaturated monomer in the presence of poly(phenylene ether) or a poly(phenylene ether) copolymer to make the amphiphilic block copolymer. A porous asymmetric membrane comprises a poly(phenylene ether) or poly(phenylene ether) copolymer, and the amphiphilic block copolymer comprising a poly(phenylene ether) block or a poly(phenylene ether) copolymer block, and a hydrophilic block or graft. The porous asymmetric membrane is made by phase-inversion of a dope solution of the poly(phenylene ether) or poly(phenylene ether) copolymer and the amphiphilic block copolymer in a coagulation bath.