KR-20260067461-A - CERAMIC HOLLOW FIBER MEMBRANE COATED WITH NANO-GRAPHITE AND METHOD FOR PREPARING SAME

Abstract

The present invention relates to a ceramic hollow fiber membrane coated with nanographite and a method for manufacturing the same. Specifically, the invention provides a coated ceramic hollow fiber membrane and a method for manufacturing the same, comprising: a hollow tubular ceramic support having pores formed therein; and a coating layer disposed on the outer surface of the ceramic support, wherein the coating layer is a nanographite coating layer coated with nanographite. According to the present invention, a ceramic hollow fiber membrane for water treatment coated with nanographite has the advantage of being able to maintain filtration performance by forming a nanographite coating layer, thereby lowering the reduction rate of filtration volume, and also having a coating layer that is more economical because it has superior ion removal performance, such as fluoride removal performance, compared to an uncoated ceramic hollow fiber membrane, and has a low coating cost, thereby providing a ceramic hollow fiber membrane for water treatment coated with nanographite with improved filtration performance.

Inventors

• 박찬혁
• 김소연
• 김혜율
• 정예빈

Assignees

• 이화여자대학교 산학협력단

Dates

Publication Date

20260513

Application Date

20241105

Claims (9)

1. A hollow tubular ceramic support with formed pores; and It includes a coating layer disposed on the outer surface of the ceramic support, and A coated ceramic hollow fiber membrane characterized in that the above coating layer is a nanographite coating layer coated with nanographite, which is a surface-modified nanomaterial.
2. A coated ceramic hollow fiber membrane according to claim 1, characterized in that the ceramic support comprises at least one of alumina ( Al₂O₃ ), titania ( TiO₂ ), zirconia ( ZrO₂ ), and silicon carbide (SiC).
3. A coated ceramic hollow fiber membrane according to claim 1, characterized in that the pore size of the ceramic support is 0.01 μm to 2 μm.
4. A coated ceramic hollow fiber membrane according to claim 1, characterized in that the nano-graphite has a size of 20 nm to 200 nm and the thickness of the coating layer is 50 μm to 200 μm.
5. A hollow fiber membrane module comprising at least one ceramic hollow fiber membrane of claim 1; A housing in which an internal long-term hollow fiber membrane module is placed; and A water treatment module comprising an inlet and an outlet formed spaced apart from each other in the above housing.
6. A step of providing a hollow tubular ceramic support with formed pores (Step 1); and The method includes the step (step 2) of forming a coating layer on the outer surface of the ceramic support, and The above step 2 is A nanographite solution is prepared by dispersing nanographite, a surface-modified nanomaterial, in a solvent, and The above nanographite solution is coated on the outer surface of the ceramic support, and including drying this A method for manufacturing a ceramic hollow fiber membrane for water treatment, characterized by
7. A method according to claim 6, characterized in that the concentration of the nano-graphite solution in step 2 is 25 mg/L to 1000 mg/L.
8. A method according to claim 6, characterized in that, in step 2 above, the coating is performed by at least one of dip coating, spray coating, and pressure filtration coating.
9. A method according to claim 6, characterized in that the thickness of the coating layer dried in step 2 is 50 μm to 200 μm.

Description

Ceramic Hollow Fiber Membrane Coated with Nano-Graphite and Method for Preparing Same The present invention relates to a ceramic hollow fiber membrane and a method for manufacturing the same, specifically, a coated ceramic hollow fiber membrane for water treatment and a method for manufacturing the same. With the advancement of industry, the harmful effects of hazardous substances generated in various industrial processes, such as dust, soot, exhaust gases, smoke, and volatile organic compounds (VOCs), are on the rise. Consequently, while polymer filters are used in some areas to prevent the release of these pollutants, they have drawbacks regarding heat resistance, chemical resistance, wear resistance, and flame retardancy. Therefore, ceramic filters have been developed to solve these problems. Ceramic filters have characteristics such as heat resistance, chemical resistance, and wear resistance that are much superior to those of polymer filters. In particular, they have excellent heat resistance, so there is no need to install a separate cooling device in the exhaust system, which has the advantage of reducing installation and maintenance costs. Membrane filtration processes using nanofiltration membranes (NF) are gaining attention as advanced water treatment processes because they have the advantage of being able to maintain a relatively high membrane flux compared to reverse osmosis (RO) filtration processes and remove even low molecular weight organic matter. Filtration membrane materials primarily used in nanofiltration membrane (NF) processes are composed of polymers that are relatively inexpensive and easy to manufacture, but they have the disadvantage of being vulnerable to high temperatures and organic solvents. To overcome this, research and technological development are actively underway , primarily in Japan, for ceramic nanofiltration membranes made of inorganic materials that offer excellent heat resistance, chemical resistance, and pressure resistance, as well as semi-permanent usability, utilizing various materials such as Al₂O₃ , TiO₂ , and ZrO₂ . However, ceramic membranes currently remain at the level of microfiltration and ultrafiltration, and ceramic nanofiltration technology has not advanced significantly. In particular, domestic ceramic nanofiltration technology is virtually non-existent. Meanwhile, ceramic hollow fiber membranes offer excellent and cost-effective performance for fluid filtration applications. As they are inherently chemically inert, ceramics are superior materials for process applications where conventional polymer membranes are unsuitable due to high pressure, high temperature, or extreme pH. Ceramic hollow fiber membranes prevent bacteria and other impurities from adhering to the membrane surface, thereby extending the lifespan of filtration systems and lowering the total cost of ownership. Ceramic hollow fiber membranes are widely used in industries such as biotechnology, chemical processing, water and wastewater treatment, pharmaceuticals, and food and beverage processing. However, in order to further improve filtration and removal performance and provide ceramic hollow fiber membranes usable in advanced water purification processes, research is needed not only on the materials, size, and structure of the ceramic hollow fiber membranes but also on the coating layer appropriately applied to them. The prior art in the technical field described above is as follows. Korean Patent Registration No. 10-2641726 (Registration Date: February 23, 2024) relates to a ceramic hollow fiber membrane for water treatment, a water treatment module, and a method for manufacturing a ceramic hollow fiber membrane for water treatment. Specifically, it relates to a ceramic hollow fiber membrane for water treatment comprising: a hollow tubular ceramic support having pores formed therein; and a coating layer disposed on the outer surface of the ceramic support containing activated carbon particles. The above patent only uses activated carbon particles as a coating layer and does not teach or imply a nano-graphite coating layer having excellent filtration and removal performance while having a low coating cost, as in the present invention. In addition, Korean Patent Registration No. 10-2427811 (Registration Date: July 27, 2022) relates to a surface-modified ceramic hollow fiber membrane, a membrane contactor including the same, and a method for manufacturing the same. Specifically, it relates to a surface-modified ceramic hollow fiber membrane comprising a hydrophilic inorganic material; and a hydrophobic surface modification layer formed on the surface of the hydrophilic ceramic hollow fiber membrane and comprising a hydrophobic material, a membrane contactor including the same, and a method for manufacturing the same. The aforementioned patent includes only a hydrophobic surface modification layer as a coating layer and does not teach or imply a nano-graphite coating layer having excelle