Toray Industries, Inc.

Harutoki Shimura

Yohei Adachi

Takafumi Ogawa

Takaaki Yasuda

Takahiro Tokuyama

Kohei Kuraoka

Yoshiki Nishiguchi

Shinya Mitsui

Masahiro Kimura

Takao Sasaki

Masakazu Koiwa

Koji Nakatsuji

Tsuyoshi Hamada

Yoshie Marutani

Masami Ogata

Tomoya Yoshizaki

Kiyohiko Takaya

Kumiko Ogawa

A composite semipermeable membrane, including: a microporous support layer; and a separation functional layer provided on the microporous support layer, in which the separation functional layer includes a crosslinked wholly aromatic polyamide which is a polycondensation product of a polyfunctional aromatic amine and a polyfunctional aromatic acid chloride and contains amino groups and carboxyl groups, and in positive secondary ions measured on a surface of the separation functional layer by time-of-flight secondary ion mass spectrometry, when (count number of m/z=104.03)/(count number of m/z=108.06) is denoted by a, and a molar ratio (carboxyl group/amino group) of the carboxyl group to the amino group, which is obtained by analyzing the entire separation functional layer byC solid state NMR, is denoted by b, the following formulae (1) and (2) are satisfied: a≥5.0 (1); and a/b≥4.3 (2).

Composite semipermeable membrane

The present invention relates to a composite semipermeable membrane including: a support membrane including a base and a porous support layer; and a separation functional layer disposed on the porous support layer and including a crosslinked aromatic polyamide, in which the separation functional layer contains sulfo groups in an amount of 7.0×10to 5.0×10g/mand includes a structure represented by the formula 1.

Composite semi-permeable membrane

The present invention relates to a composite semipermeable membrane including: a substrate; a porous support layer disposed on the substrate; and a separation functional layer disposed on the porous support layer, in which the separation functional layer includes: a first layer including a crosslinked aromatic polyamide; and a coating layer existing on the first layer and including an aliphatic polyamide including a fluorine atom, and the composite semipermeable membrane has a proportion of the number of fluorine atoms to the total number of atoms of all elements of 0.5% or more and 8% or less, and has a ratio (N/O ratio) of the number of nitrogen atoms to the number of oxygen atoms of 0.8 or more and 1.3 or less.

A novel membrane is provided in which the permeate flow rate is not prone to decrease even when the membrane is used to process seawater with high salt concentration and high heavy metal ion concentration. This composite semipermeable membrane comprises a porous support layer, a separation function layer arranged on the porous support layer, and a coating layer coating the separation function layer, wherein the separation function layer contains a crosslinked polymer amide which is a condensate of polyfunctional aromatic amine and polyfunctional aromatic acid chloride, and the coating layer contains an aliphatic polymer including a polyether moiety and a carbonic acid polymer moiety.

Composite semipermeable membrane and composite semipermeable membrane element

A composite semipermeable membrane includes a porous supporting membrane and a separation functional layer, in which, in cross-sections having a length of 2.0 &#x3bc;m in a membrane surface direction, the average number density of projections in the separation functional layer which have a height of one-fifth or more of the 10-point average surface roughness is 10.0-30.0 projections/&#x3bc;m and the projections have an average height less than 100 nm, and in which a water production rate and a salt rejection are predetermined values or more after an aqueous solution is passed through under certain conditions.

By having a coating layer, this composite semipermeable membrane has fouling resistance easily maintainable before and after contact with acid, and enables stable operation over a long period of time. This composite semipermeable membrane comprises a porous support layer, a separation function layer arranged on the porous support layer, and a coating layer arranged on the separation function layer, wherein the separation function layer contains a crosslinked aromatic polyamide which is a polycondensate of polyfunctional aromatic amines and polyfunctional aromatic acid chloride, and the coating layer contains an aliphatic polymer having the structure (I) in the description.

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Shiga, Japan

Harutoki Shimura