NANOFIBER BASED OIL-WATER SEPARATION AND PURIFICATION MATERIAL HAVING A SHIFTED INCLINED-HOLE STRUCTURE AND PREPARATION METHOD THEREOF

Abstract

In a method for preparing a nanofiber based oil-water separation and purification material having a shifted inclined-hole structure, firstly, a melt-spinning method is used for preparing a multi-layer fiber membrane, and then according to the requirements of the size, number and arrangement of holes on each layer of fiber membrane, a puncher is used for punching inclined frustum cone-shaped through holes on the fiber membrane. Finally, according to the requirements of relative positions of the inclined frustum cone-shaped through holes on fiber membranes in different layers, multiple layers of fiber membranes are composited to prepare a nanofiber based oil-water separation and purification material having a shifted inclined-hole structure. The oil-water separation and purification material is a multi-layer composite fiber membrane. Each layer of fiber membrane has a plurality of uniformly distributed inclined frustum cone-shaped through holes.

Claims

1. A nanofiber based oil-water separation and purification material having a shifted inclined-hole structure, wherein the material is a multi-layer composite fiber membrane, each layer of the fiber membrane has a plurality of uniformly distributed inclined frustum cone-shaped through holes, and a large end of each of the frustum cone-shaped through holes is upward, and a small end of each of the frustum cone-shaped through holes is downward; large ends of any two adjacent inclined frustum cone-shaped through holes in each layer of the fiber membrane are tangent to each other; each frustum cone in shape through hole in each layer of the fiber membrane has one corresponding frustum cone-shaped through hole in an under layer of the fiber membrane; and the small end of the each frustum cone-shaped through hole in each layer of fiber membrane communicates with the large end of the one corresponding inclined frustum cone-shaped through hole in the under layer of the fiber membrane; all of the inclined frustum cone-shaped through holes have an identical size, an identical inclination direction and an identical inclination angle; a percentage of a sum of areas of large ends of all of the inclined frustum cone-shaped through holes in each layer of the fiber membrane to a unilateral surface area of the each layer of the fiber membrane is 80 to 90%; and each layer of the fiber membrane is made of oleophylic hydrophobic nanofibers.

2. The nanofiber based oil-water separation and purification material according to claim 1, wherein the oleophylic hydrophobic nanofibers are made of polyvinylidene fluoride, polyethersulfone, polysulfone, polypropylene, polyethylene, polyester or polyvinyl butyral.

3. The nanofiber based oil-water separation and purification material according to claim 2, wherein the oleophylic hydrophobic nanofibers have an average diameter of 50 to 800 nm.

4. The nanofiber based oil-water separation and purification material according to claim 1, wherein the fiber membrane has 3 to 5 layers.

5. The nanofiber based oil-water separation and purification material according to claim 1, wherein each of the inclined frustum cone-shaped through holes has a diameter of 80 to 200 m at the large end, a diameter of 20 to 60 m at the small end, a height of 2 to 40 m, and an inclination angle of 20 to 70.

6. The nanofiber based oil-water separation and purification material according to claim 1, wherein a number of one of rows or columns of the inclined frustum cone-shaped through holes per square meter on a unilateral surface of the fiber membrane is 5,000 to 12,000.

7. The nanofiber based oil-water separation and purification material according to claim 1, wherein a flux of the nanofiber based oil-water separation and purification material is greater than 2500 L/m.sup.2h, and a separation efficiency of the nanofiber based oil-water separation and purification material is greater than 99.99%.

8. A preparation method of the nanofiber based oil-water separation and purification material according to claim 1, comprising: firstly, preparing a plurality of fiber membranes by using a melt-spinning method, then according to requirements on the size, number and arrangement of the through holes on each of the plurality of fiber membranes, punching the inclined frustum cone-shaped through holes on the plurality of fiber membranes by using a puncher, and finally, according to requirements on relative positions of the inclined frustum cone-shaped through holes on each layer of the composite fiber membrane, compounding the plurality of fiber membranes to obtain the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure; wherein a compounding apparatus having a laser positioner is used for compounding.

9. The preparation method according to claim 8, wherein process parameters of the melt-spinning method are: a melting temperature of 200 to 320 C., a wind temperature of 200 to 320 C., a die head temperature of 180 to 320 C., and a fan frequency of 50 Hz.

Description

BRIEF DESCRIPTION OF DRAWINGS

[0026] FIGS. 1 to 3 are schematic diagrams showing the positional relationship of the inclined frustum cone-shaped through holes on each layer of fiber membrane in the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure and the oil-water separation effect in embodiments 1, 5, and 6, respectively.

DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS

[0027] The present disclosure will be further described below in conjunction with specific embodiments. It should be understood that these embodiments are only used to illustrate the present disclosure and are not intended to limit the scope of the present disclosure. In addition, it should be understood that after reading the content taught by the present disclosure, those skilled in the art can make various changes or modifications to the present disclosure, and these equivalent forms also fall within the scope limited by the appended claims of the present application.

Embodiment One

[0028] A nanofiber based oil-water separation and purification material having a shifted inclined-hole structure, the specific steps are as follows.

[0029] (1) Three polyvinylidene fluoride fiber membranes are prepared by meltspinning. The average diameter of the fibers in the fiber membranes is 300 nm, in and the process parameters of the meltspinning are a melting temperature of 225 C., a wind temperature of 230 C., a die head temperature of 220 C., and a fan frequency of 50 Hz.

[0030] (2) A puncher is used for punching inclined frustum cone-shaped through holes on each fiber membrane so that each fiber membrane is evenly distributed with multiple inclined frustum cone-shaped through holes, and the large end of the inclined frustum cone-shaped through hole face is upward and the small end of the inclined frustum cone-shaped through hole face is downward. Seeing from the surface of each fiber membrane where the large end of the inclined frustum cone-shaped through hole is located, on average, within one square meter, each row has 8900 inclined frustum cone-shaped through holes. Large ends of any two adjacent inclined frustum cone-shaped through holes in each layer of fiber membrane are tangent to each other. All inclined frustum cone-shaped through holes have the same size, inclination direction and inclination angle. The average diameter of the large end of each inclined frustum cone-shaped through hole is 120 m, the diameter of the small end is 45 m, the height is 26 m, and the slope of the inclined cone is 46. The percentage of the sum of areas of large ends of all inclined frustum cone-shaped through holes in each layer of fiber membrane to a unilateral surface area of the each layer of fiber membrane is 82%.

[0031] (3) According to the relative position requirements of each frustum cone-shaped through hole in each layer of fiber membrane has one corresponding frustum cone-shaped through hole in an under layer of the fiber membrane communicating with the each frustum cone-shaped through hole; and the small end of the each frustum cone-shaped through hole in each layer of fiber membrane communicates with the large end of the one corresponding inclined frustum cone-shaped through hole in the under layer of the fiber membrane, three fiber membranes having inclined frustum cone-shaped through holes are composited by using a compounding apparatus having a laser locator to obtain the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure.

[0032] The final prepared nanofiber based oil-water separation and purification material having the shifted inclined-hole structure is a three-layer composite fiber membrane as shown in FIG. 1. The flux of the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure is 3476 L/m.sup.2 h, and the separation efficiency is 99.995%.

Embodiment Two

[0033] A preparation method of the nanofiber based oil-water separation and purification material having a shifted inclined-hole structure is basically the same as Embodiment one. The difference lies in that the material of the fiber membrane in step (1) is polypropylene fiber. The process parameters of meltspinning are: a melting temperature of 250 C., a wind temperature of 220 C., a die head temperature of 235 C., and a fan frequency of 50 Hz.

[0034] The flux of the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure finally obtained is 3359 L/m.sup.2 h, and the separation efficiency is 99.997%.

Embodiment Three

[0035] A preparation method of the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure is basically the same as Embodiment one. The difference lies in that the material of the fiber membrane in step (1) is polyethylene fiber. The process parameters of meltspinning are: a melting temperature of 235 C., a wind temperature of 225 C., a die head temperature of 235 C., and a fan frequency of 50 Hz. The flux of the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure finally obtained is 3841 L/m.sup.2 h, and the separation efficiency is 99.992%.

Embodiment Four

[0036] A preparation method of the nanofiber based oil-water separation and purification material having a shifted inclined-hole structure is basically the same as Embodiment one. The difference lies in that the material of the fiber membrane in step (1) is polyvinyl butyral fiber. The process parameters of meltspinning are: a melting temperature of 205 C., a wind temperature of 200 C., a die head temperature of 210 C., and a fan frequency of 50 Hz. The flux of the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure finally obtained is 4019 L/m.sup.2 h, and the separation efficiency is 99.993%.

Embodiment Five

[0037] A preparation method of the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure, the specific steps are as follows.

[0038] (1) Four polyethersulfone fiber membranes are prepared by meltspinning. The average diameter of the fibers in the fiber membranes is 800 nm, and the process parameters of the meltspinning are a melting temperature of 305 C., a wind temperature of 300 C., a die head temperature of 305 C., and a fan frequency of 50 Hz.

[0039] (2) A puncher is used for punching inclined frustum cone-shaped through holes on each fiber membrane so that each fiber membrane is evenly distributed with multiple inclined frustum cone-shaped through holes, and the large end of the inclined frustum cone-shaped through hole face is upward and the small end of the inclined frustum cone-shaped through hole face is downward. Seeing from the surface of each fiber membrane where the large end of the inclined frustum cone-shaped through hole is located, on average, within one square meter, each column has 11080 inclined frustum cone-shaped through holes. Large ends of any two adjacent inclined frustum cone-shaped through holes in each layer of fiber membrane are tangent to each other. All inclined frustum cone-shaped through holes have the same size, inclination direction and inclination angle. The average diameter of the large end of each inclined frustum cone-shaped through hole is 180 m, the diameter of the small end is 55 m, the height is 35 m, and the slope of the inclined cone is 38. The percentage of the sum of areas of large ends of all inclined frustum cone-shaped through holes in each layer of fiber membrane to a unilateral surface area of the each layer of fiber membrane is 86%.

[0040] (3) According to the relative position requirements of each frustum cone-shaped through hole in each layer of fiber membrane has one corresponding frustum cone-shaped through hole in an under layer of the fiber membrane communicating with the each frustum cone-shaped through hole; and the small end of the each frustum cone-shaped through hole in each layer of fiber membrane communicates with the large end of the one corresponding inclined frustum cone-shaped through hole in the under layer of the fiber membrane, four fiber membranes having inclined frustum cone-shaped through holes are composited by using a compounding apparatus having a laser locator to obtain the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure.

[0041] The final prepared nanofiber based oil-water separation and purification material having a shifted inclined-hole structure is a four-layer composite fiber membrane as shown in FIG. 2. The flux of the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure is 4430 L/m.sup.2 h, and the separation efficiency is 99.999%.

Embodiment Six

[0042] A preparation method of the nanofiber based oil-water separation and purification material having a shifted inclined-hole structure, the specific steps are as follows.

[0043] Five polysulfone fiber membranes are prepared by meltspinning. The average diameter of the fibers in the fiber membranes is 550 nm, and the process parameters of the meltspinning are a melting temperature of 285 C., a wind temperature of 290 C., a die head temperature of 290 C., and a fan frequency of 50 Hz.

[0044] A puncher is used for punching inclined frustum cone-shaped through holes on each fiber membrane so that each fiber membrane is evenly distributed with multiple inclined frustum cone-shaped through holes, and the large end of the inclined frustum cone-shaped through hole face is upward and the small end of the inclined frustum cone-shaped through hole face is downward. Seeing from the surface of each fiber membrane where the large end of the inclined frustum cone-shaped through hole is located, on average, within one square meter, each row has 9089 inclined frustum cone-shaped through holes. Large ends of any two adjacent inclined frustum cone-shaped through holes in each layer of fiber membrane are tangent to each other. All inclined frustum cone-shaped through holes have the same size, inclination direction and inclination angle. The average diameter of the large end of each inclined frustum cone-shaped through hole is 168 m, the diameter of the small end is 28 m, the height is 22 m, and the slope of the inclined cone is 58. The percentage of the sum of areas of large ends of all inclined frustum cone-shaped through holes in each layer of fiber membrane to a unilateral surface area of the each layer of fiber membrane is 88%.

[0045] According to the relative position requirements of each frustum cone-shaped through hole in each layer of fiber membrane has one corresponding frustum cone-shaped through hole in an under layer of the fiber membrane communicating with the each frustum cone-shaped through hole; and the small end of the each frustum cone-shaped through hole in each layer of fiber membrane communicates with the large end of the one corresponding inclined frustum cone-shaped through hole in the under layer of the fiber membrane, five fiber membranes having inclined frustum cone-shaped through holes are composited by using a compounding apparatus having a laser locator to obtain the nanofiber based oil-water separation and purification material having the shifted inclined-hole structure.

[0046] The final prepared nanofiber based oil-water separation and purification material having the shifted inclined-hole structure is a five-layer composite fiber membrane as shown in FIG. 3. The flux of the nanofiber based oil-water separation and purification material having a shifted inclined-hole structure is 4509 L/m.sup.2 h, and the separation efficiency is 99.999%.