A device for rapidly and efficiently separating and extracting micro / nano plastics

Abstract

The application provides a device for quickly and efficiently separating and extracting micro / nano plastics, which comprises an upper push-off pool, an upper glass plate, a lower glass plate, a lower separation pool, and the upper glass plate and the lower glass plate are horizontally and slidably connected; the upper push-off pool is a hollow cylinder with two open ends and is fixedly connected with the upper glass plate; the lower separation pool is open at the upper end and is fixedly connected with the lower glass plate; the opening of the upper push-off pool is aligned with / pushed away from the opening of the lower separation pool; when the openings are aligned, the upper push-off pool and the lower separation pool are in communication; when the openings are pushed away, the upper glass plate blocks the upper opening of the lower separation pool, and the lower glass plate blocks the lower opening of the upper push-off pool. The device is used to solve the problems of large amount of flotation liquid, long time consumption, easy damage to the solid-liquid stable system after flotation and standing, and high impurity content in the sample after separation and extraction in the traditional separation and extraction device, and provides a basis for evaluating the characteristics and abundance of micro / nano plastics in environmental samples.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of solid waste treatment, and particularly relates to a device for separating and extracting micro / nano plastics in an environmental sample. BACKGROUND

[0002] Micro / nano plastics refer to plastic fragments, fibers, particles, foams or films with a diameter of less than 5 mm in the environment. With the large-scale production and use of plastic products, micro / nano plastics, as a new type of pollutant widely existing in the environment, have gradually attracted people's attention. However, due to their non-degradable properties, they can exist in water bodies and terrestrial ecosystems for a long time. How to quickly and efficiently separate and extract micro / nano plastics in environmental samples is an important basis for related research.

[0003] For the separation of micro / nano plastics in soil and sediments and environmental samples, the most commonly used method is density flotation, that is, using a high-density flotation liquid to float the micro / nano plastics in the environmental sample to the uppermost layer. The flotation liquid is usually saturated NaCl solution (1.2 g / cm 3 ), ZnCl2 solution (1.6 g / cm 3 ) and NaI solution (1.8 g / cm 3 ) and the like. Due to the differences in reagents and device selection among different studies, the results of different studies are difficult to compare directly, and therefore it is necessary to establish a standardized method for separating and extracting micro / nano plastics from environmental samples.

[0004] Based on the characteristics of micro / nano plastics, the traditional devices for separating micro / nano plastics, such as separatory funnels, test tubes or beaker overflow, have the problems of large amount of flotation liquid, easy to damage the solid-liquid stable system after standing, long time-consuming and the like. In order to solve the above problems, the manual extraction device for quickly and efficiently separating micro / nano plastics in soil and sediments is designed. SUMMARY

[0005] The purpose of the application is to provide a device for quickly and efficiently separating and extracting micro / nano plastics, which solves the problems of large amount of flotation liquid, long time-consuming, easy to damage the solid-liquid stable system after flotation standing and high impurity content in the sample after separation and extraction in the traditional device, and provides a basis for evaluating the characteristics and abundance of micro / nano plastics in environmental samples.

[0006] To achieve the above purpose, the application is implemented by the following technical solutions:

[0007] The device for separating and extracting micro / nano plastics quickly and efficiently comprises an upper pushing-off pool, an upper glass plate, a lower glass plate, a lower separation pool, and the upper glass plate and the lower glass plate are horizontally and slidably connected; the upper pushing-off pool is a hollow cylinder with two open ends and is fixedly connected with the upper glass plate; the lower separation pool is open at the upper end and is fixedly connected with the lower glass plate; the upper pushing-off pool is aligned with / pushed away from the opening of the lower separation pool; when aligned, the upper pushing-off pool and the lower separation pool are in communication; when pushed away, the upper glass plate blocks the upper opening of the lower separation pool and the lower glass plate blocks the lower opening of the upper pushing-off pool.

[0008] Preferably, the upper pushing-off pool and the lower separation pool have the same opening size.

[0009] The device for manually separating and extracting micro / nano plastics provided by the application comprises a separation pool and a pushing-off pool.

[0010] When aligned, the separation pool is formed, that is, the separation pool is composed of the upper and lower two parts aligned after horizontal sliding, and the pushing-off pool is composed of the lower glass plate and the hollow cylinder with two open ends (the upper pushing-off pool).

[0011] Preferably, the lower glass plate is provided with grooves on both sides, and the upper glass plate is slidably inserted into the grooves. Vaseline is coated between the upper glass plate and the lower glass plate. The glass plates are connected in a sealed manner through the coating of Vaseline and the frosted surface, and meanwhile, the clamping grooves on both sides of the lower glass plate are used to ensure the air tightness of the device and the relative sliding in the horizontal direction.

[0012] Preferably, the upper glass plate is symmetrically provided with upper limiting holes, the lower glass plate is symmetrically provided with lower limiting holes, and when the opening of the upper pushing-off pool is aligned with the opening of the lower separation pool, the upper limiting holes are aligned with the lower limiting holes. When the device is assembled into the separation pool, it is necessary to position according to the four sets of limiting holes to ensure the stability of the device. After the sample is uniformly mixed with a certain amount of flotation liquid, the mixture is poured into the separation pool, and when the device is switched from the separation pool to the pushing-off pool, the upper device needs to be slowly pushed until the outer edges of the glass plates are aligned, and the liquid in the separation pool is transferred to the collection device.

[0013] The flotation liquid can be selected from one of saturated NaCl solution (1.2 g / cm 3 ), ZnCl2 solution (1.6 g / cm 3 ), and NaI (1.8 g / cm 3 ) according to different samples.

[0014] The device solves the problems of traditional separating funnel, such as easy to destroy solid-liquid stable system, poor separation effect; compared with the common overflow method, the separation efficiency of the device is higher, and the influence on the stable system after standing is smaller; compared with the newly developed control separation valve and one-way overflow device, the device is made of quartz glass material, without plastic composition, avoiding the problem of plastic pollution caused by the device in the separation and extraction process; using the device, the amount of floating liquid is small, and can be recycled. Especially when ZnCl2 is used as the floating liquid, it not only saves resources, but also does not harm the environment.

[0015] Compared with the traditional separating funnel separation, the device solves the problems of separation process, such as easy to destroy solid-liquid stable system, soil or sediment easy to block the piston; the device is made of quartz glass material, compared with the improved control separation valve, avoiding the problem of contacting plastic in the separation process, which will not harm the environment, and reducing the retention of micro / nano plastic in the extraction process; compared with the commonly used overflow device, the device solves the problems of large amount of floating liquid, uncertain flow direction of overflowed floating liquid, and difficult collection; compared with the improved one-way overflow device, the device also avoids the problem of contacting plastic in the separation process, and through the design of vaseline, ground glass surface and clamping groove, the air tightness of the upper and lower devices is guaranteed, there is no position easy to retain micro / nano plastic, and the recovery rate of micro / nano plastic is high. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 The left view of the micro / nano plastic separation and extraction device provided by the application;

[0017] Figure 2 The main view of the micro / nano plastic separation and extraction device provided by the application is aligned;

[0018] Figure 3 The main view of the micro / nano plastic separation and extraction device provided by the application is pushed away;

[0019] Figure 4 The top view of the micro / nano plastic separation and extraction device provided by the application.

[0020] Among them, 1 is the upper layer push-off pool, 3 is the upper layer glass plate, 4 is the lower layer glass plate, 5 is the lower layer separation pool, 21 is the lower layer limiting hole, and 22 is the upper layer limiting hole. DETAILED DESCRIPTION

[0021] The application will be further described below in combination with examples.

[0022] Example 1

[0023] As Figures 1-3As shown, the present example provides a device for rapid and efficient separation and extraction of micro / nano plastics, which comprises an upper push-off pool 1, an upper limiting hole 22, a lower limiting hole 21, an upper glass plate 3, a lower glass plate 4, and a lower separation pool 5. The upper push-off pool 1 is a hollow cylinder with open ends and is fixedly connected with the upper glass plate 3; the lower separation pool 5 is open at the upper end and is fixedly connected with the lower glass plate 4;

[0024] In the present example, the device has a lower separation pool height of 14 cm, an upper push-off pool height of 6 cm, a pipe opening outer diameter of 4 cm, and a thickness of 0.1 cm. The glass plate connecting the upper and lower layers has a frosted surface, a single piece thickness of 0.3 cm, and a total height of 20.6 cm. Each glass plate is provided with four limiting holes with a diameter of 0.2 cm, a distance of 0.5 cm from the edge of the upper glass plate, and a distance of 0.8 cm from the edge of the lower glass plate. After sliding the upper and lower layers, the horizontal distance between the two pipes is 3 cm. The device is suitable for soil or sediment with a sample mass of 50-150 g, and about 120 mL of flotation liquid can be added to meet the push-off requirements. Those skilled in the art can also make appropriate adjustments to the parameters according to actual needs.

[0025] In use, the device needs to be coated with vaseline between the upper glass plate 3 and the lower glass plate 4 to ensure the air tightness of the upper and lower devices. The upper glass plate 3 is inserted into the clamping groove of the lower glass plate 4, positioned according to the four sets of limiting holes, and the upper and lower pipe openings are aligned to prevent micro / nano plastics from remaining in the middle position. After mixing the sample with a certain amount of flotation liquid and adding it to the device, mix thoroughly. If the liquid level of the mixture does not exceed the upper glass plate 3 in the middle of the device at this time, add flotation liquid from the upper pipe opening to exceed the middle interface, and wait for density flotation to complete. After flotation is completed, gently push the upper device along the horizontal direction of the upper glass plate 3 and the lower glass plate 4 until the outer edges of the glass plates are aligned. At this time, the upper glass plate 3 can exactly block the top opening of the lower separation pool 5, and the lower glass plate 4 can exactly block the bottom opening of the upper push-off pool 1. The flotation liquid containing micro / nano plastics is retained in the upper push-off pool 1. This part of the liquid is transferred to the collection device for subsequent processing, and the separation of micro / nano plastics is completed.

[0026] In the present example, the collection device is preferably a beaker, and those skilled in the art can also select other containers according to needs as long as they can contain the flotation liquid containing micro / nano plastics in the push-off pool.

Claims

1. A device for rapid and efficient separation and extraction of micro / nano plastics, comprising an upper push-off pool (1), an upper glass plate (3), a lower glass plate (4), and a lower separation pool (5), characterized in that, The upper glass plate (3) and the lower glass plate (4) are horizontally slidably connected; the upper push-off pool (1) is a hollow cylinder with two open ends and is fixedly connected with the upper glass plate (3); the lower separation pool (5) is open at the upper end and is fixedly connected with the lower glass plate (4); the upper push-off pool (1) is aligned with the lower separation pool (5) in opening / push-off; when aligned, the upper push-off pool (1) and the lower separation pool (5) are communicated; when pushed off, the upper push-off pool (1) and the lower separation pool (5) are blocked in opening by relative lateral sliding, so as to achieve the purpose of separation.

2. The device for rapid and efficient separation and extraction of micro / nano plastics according to claim 1, characterized in that, The upper glass plate (3) blocks the top opening of the lower separation pool (5), and the lower glass plate (4) blocks the bottom opening of the upper push-off pool (1).

3. The device for rapid and efficient separation and extraction of micro / nano plastics according to claim 1, characterized in that, The lower glass plate (4) is provided with grooves on both sides, and the upper glass plate (3) is slidably inserted into the grooves.

4. The device for rapid and efficient separation and extraction of micro / nano plastics according to claim 1, characterized in that, The upper glass plate (3) and the lower glass plate (4) are coated with vaseline.

5. The device for rapid and efficient separation and extraction of micro / nano plastics according to claim 1, characterized in that, The upper push-off pool (1) and the lower separation pool (5) have the same opening size.

6. The device for rapid and efficient separation and extraction of micro / nano plastics according to claim 1, characterized in that, The upper glass plate (3) is symmetrically provided with upper limiting holes (22), the lower glass plate (4) is symmetrically provided with lower limiting holes (21), and when the upper push-off pool (1) is aligned with the lower separation pool (5) in opening, the upper limiting holes (22) are aligned with the lower limiting holes (21).

7. The device for rapid and efficient separation and extraction of micro / nano plastics according to claim 1, characterized in that, The materials of the upper push-off pool (1), the upper glass plate (3), the lower glass plate (4) and the lower separation pool (5) are all quartz glass.

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