Water treatment separation membrane, water treatment module comprising same, and manufacturing method therefor
Provided is a water-treatment membrane including a porous support; and a polyamide active layer including chlorine on a surface thereof, wherein CIE L*a*b* color coordinate values after storing for 30 days or longer at 25° C. to 80° C. satisfy Equation 1 to Equation 3: 91< L *<97 <Equation 1> −1.5< a *<1.5 <Equation 2> −1.5< b *<8 <Equation 3> of the present disclosure, a water-treatment module including the same, and a method for manufacturing the same.
1. A water-treatment membrane comprising:
a porous support;
a polyamide active layer provided on the porous support and including chlorine on a surface thereof, wherein a chlorine element content measured by an elemental analysis on the surface of the polyamide active layer is greater than 0 at % and less than or equal to 3 at %; and
a protective layer including glycerin on the polyamide active layer,
wherein CIE L*a*b* color coordinate values after storing for 30 days or longer at 25° C. to 80° C. satisfy the following <Equation 1> to <Equation 3>:
91< L*< 97 Equation 1>
−1.5< a*< 1.5 Equation 2>
−1.5< b*< 8 <Equation 3>.
2. A water-treatment module comprising one or more of the water-treatment membranes of claim 1 .
3. A method for manufacturing the water-treatment membrane of claim 1 , the method comprising:
(a) forming a polyamide active layer on a porous support by interfacial polymerizing an amine compound and an acyl halide compound;
(b) pretreating the polyamide active layer by bringing the polyamide active layer into contact with a pretreatment solution including water;
(c) bringing a hypochlorite solution having a concentration of 50 ppm to 300 ppm into contact with the pretreated polyamide active layer for 1 second to 1 minute; and
(d) forming a protective layer by coating an aqueous glycerin solution on the polyamide active layer.
4. The method of claim 3 , wherein a moisture content of the water-treatment membrane measured immediately after (a) is from 0.1% to 3%.
5. The method of claim 3 , wherein a moisture content of the water-treatment membrane measured immediately after (b) is from 20% to 50%.
6. The method of claim 3 , wherein a moisture content of the water-treatment membrane measured immediately after (d) is from 0.1% to 5%.
7. The method of claim 3 , wherein the pretreatment solution further includes one or more types of an acidic salt or a basic salt.
8. The method of claim 3 , wherein the hypochlorite solution is an aqueous sodium hypochlorite solution.