CN106769356A - A kind of micro- plastics extraction element and its method for preventing sample by microfibre pollution - Google Patents

A kind of micro- plastics extraction element and its method for preventing sample by microfibre pollution Download PDF

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Publication number
CN106769356A
CN106769356A CN201611100598.7A CN201611100598A CN106769356A CN 106769356 A CN106769356 A CN 106769356A CN 201611100598 A CN201611100598 A CN 201611100598A CN 106769356 A CN106769356 A CN 106769356A
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China
Prior art keywords
pollution
micro
microfibre
conical flask
plastics
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CN201611100598.7A
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Chinese (zh)
Inventor
刘新会
韩磊
梁宝翠
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Beijing Normal University
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Beijing Normal University
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    • GPHYSICS
    • G01MEASURING; TESTING
    • G01NINVESTIGATING OR ANALYSING MATERIALS BY DETERMINING THEIR CHEMICAL OR PHYSICAL PROPERTIES
    • G01N1/00Sampling; Preparing specimens for investigation
    • G01N1/28Preparing specimens for investigation including physical details of (bio-)chemical methods covered elsewhere, e.g. G01N33/50, C12Q
    • G01N1/34Purifying; Cleaning

Abstract

A kind of micro- plastics extracting method of deposit that sample can be prevented to be subject to microfibre pollution in environment in processing procedure.The invention belongs to micro- plastics separation technology field in environmental monitoring and water body deposit, separation and Extraction is carried out to the high score subclass particulate matter (micro- plastics) in deposit compared with low-density using saturated nacl aqueous solution as separating medium.The particulate matter that will swim in mixed liquor surface using special glass suction pipe is shifted, and is reused special ceramic device and is blotted liquid, and obtains extract in container 2.Extract in the container can directly carry out subsequent purification purified treatment.Completed in closed vessel from purification process is extracted, to prevent in air and periphery object drops the pollution of fiber.

Description

A kind of micro- plastics extraction element and its method for preventing sample by microfibre pollution
Technical field:
The invention belongs to micro- plastics separation technology field in environmental monitoring and water body deposit, totally enclosed density point is used From method, can extract water body deposit in micro- plastics while prevent air in and periphery object drop microfibre to sample Pollution.
Background technology:
Micro- plastics are the emerging environmental contaminants of a class, most laggard by all means after plastic products are discarded by the mankind In entering ocean.Plastic flakes of the diameter below 5 millimeters, are referred to as micro- plastics, including primary micro- plastics and secondary micro- plastics, enter The modeling of the small particle in entering the plastics products of the microsize in environment and being lost to natural environment during production and transport Material feed particles constitute primary micro- plastics, and the larger plastic article entered in natural environment is in the physics such as ultraviolet oxygen and heat Gradually weathering fragmentation forms secondary micro- plastics under electrochemical conditions.Tiny plastic grain eaten by mistake as food by marine organisms after meeting The Energy intaking and then influence for reducing bion grow.Plastics are the high molecular polymers of highly stable difficult degradation, As long as can there is upper a century in natural environment, finally converge and accumulate into the plastic waste material in environment by all means In ocean, the hydrophobic surface of plastics can also efficiently be combined with various sustainability organic pollutions.It is permanent and far-reaching to produce Influence.
As a kind of emerging pollutant, the micro- plastics extraction and separation technology not passed through at present.In the research of early stage In, the bulk plastic fragment for spreading on the beach can be obtained easily, of interest with the further investigation to these plastic flakes Size it is also less and less, separating difficulty is increasing.Micro- plastics of the millimeter of diameter 5 can be differentiated with the naked eye, can be made Separation and Extraction is carried out to it with sieve, and micro- plastics naked eyes of the diameter below 1 millimeter are difficult to differentiate, and extract difficulty higher.Together When pollution of the micro fiber to sample extracted in operating environment become can not ignore.These micro fibers and deposition of interest Part extract has same feature in thing, greatly disturbs follow-up micro- plastic analysis detection, have impact on the standard of data Exactness and reliability.Nuelle etc. has found some micro fibers in as the blank sample of control, Binding experiment room environmental Analysis infers that the clothing of experiment operator is primary pollution source.Identical is have also discovered in previous experiments of the invention to show As, and drawn similar conclusion.The research of Woodall simultaneously is also had also, it was found that and being kept away using judicial expertise method Exempt from the pollution of micro- plastic sample, but the common environmentology laboratory of dustfree environment required in the method is difficult to.Moral The micro- plastics extraction element in Manchester of the Imhof of state has organic efficiency higher, but the device volume is big, and cost is high, Complex operation, as Density Separation medium, and does not relate to prevent using to the disagreeableness saturation liquor zinci chloridi of environment The measure that sample is contaminated.The sieve used for the micro- plastics of 5 mm dias floats micronic dust in can not intercepting surrounding enviroment Pollution to sample, cumbersome operation can also increase the chance that mixture system is externally exposed environment in sample transfer process. Prevent that sample is contaminated it is critical only that the process for separating deposit and micro- plastic grain using Density Separation medium should be Carried out under closed environment completely, and the container conduit that is touched of mixture etc. all should keep clean dustless.This covering device Middle use micropore ceramics material and vacuum system simplify operating process instead of sieve removal Density Separation liquid, while being also to carry The follow-up purified treatment for taking thing is provided convenience.So far, ceramic material and vacuum system are used in water body deposit The extraction of micro- plastics simultaneously prevents sample to be subject to the method that air and periphery object pollute to have not been reported simultaneously.With aforementioned approaches method Compare, the apparatus structure is simple, low cost, have to the micro- plastics of trace deposit below one millimeter of diameter and reclaim effect well Really, and the pollution of floating microfibre that is prevented from common laboratory environment, special dustless or ultra-clean experiment is not required Room.
In sum, micro- plastics are as hot subject new in Environmental Studies, the environment measuring relevant with micro- plastics The exploitation of new technology is particularly urgent and crucial with improvement, is the following technical foundation for carrying out environment comprehensive monitoring, with important Significance of scientific research.A kind of wide micro- plastics extractive technique of the convenient applicability of reliability is developed to being pushed further into current micro- plastics research Significant and actual application value.
The content of the invention
A kind of sample can be prevented to be subject to micro- plastic pollution in environment in processing procedure present invention aim at providing The micro- plastics extraction element of deposit and method
Technical scheme is as follows:
A kind of 1 micro- plastics of the deposit that sample can be prevented to be subject to micro- plastic pollution in environment in processing procedure extract dress Put, including following part.
Cylindrical glass container (1), the cylindrical glass container (1) mixes with Density Separation solution for deposit and carries Take the relatively low high molecular polymerization composition granule of density;
Conical flask (2), the conical flask (2) is connected with the other end of elbow straw, the bottle sealing of the conical flask;
Dewar bottle (3), has closure at the opening of the Dewar bottle (3), is filled with micropore ceramics by connecting tube at sealing Put and be connected inside (4), ceramic device (4) is placed in conical flask (2), and the Dewar bottle (3) is by another connection on closure Pipe is connected with vavuum pump.
Elbow straw (5), the elbow straw is used to draw the floating particle in hydrostatic column (1), other end connection Silicone tube simultaneously enters in conical flask (2) through after peristaltic pump.
Micropore ceramics device (4), top layer liquid and floating particle in cylindrical glass container (1) pass through elbow straw (5) after being transferred in conical flask (2), elbow straw is removed, in the liquid that micropore ceramics device (4) is placed in conical flask (2).
Micro- plastic grain and the portion of solid are only retained after liquid is fully transferred in Dewar bottle (3) in conical flask (2), in bottle Divide impurity particle, clearing up for biological organic particle directly can be carried out in conical flask (2) and purified or dilute acid soln cleaning.
2 a kind of extracting methods for preventing sample to be subject to microfibre pollution in environment, it is characterised in that comprise the following steps:
1) sediment sample 500g to be separated is taken, is put into cylindrical glass container (1), plus 2.5L saturated sodium-chlorides are molten After liquid is sufficiently stirred for, sealing stands 6-48 hours;
2) using elbow straw and peristaltic pump (5) by the interior liquid-covered floating object of cylindrical glass container (1) and part Layer 1/3-1/2 liquid is transferred in conical flask (2);
3) porous ceramics (4) is inserted in conical flask (2), and is sealed, start vacuum system, by the liquid in conical flask (2) Body is transferred in vacuum tank (3).
4) 50ml watery hydrochloric acid rinses porous ceramics (4), by conical flask (2) sealing, treatment mixture 3-12 hours.
5) deionized water rinsing is added to filter through mixture in the container (2) after treatment, extract is retained on filter membrane.
It is preferred that, container (1) is cylindrical glass container, to reach preferable separating effect, a diameter of 12cm, height 35- 40cm.Can be adjusted according to sediment grain size using height, using preceding through fully flushing.
It is preferred that, the amount of the treatable precipitum of institute is 0.25-1kg weight in wet bases in cylindrical glass container (1), uses preshoot Wash.
It is preferred that, above-mentioned steps 1) in the standing sedimentation time can be adjusted according to sediment grain size, time of repose is more long then to be gone up Thin clay particle in layer liquid is fewer.
It is preferred that, above-mentioned steps 3) in micropore ceramics material aperture be 0.1 micron, porosity is 20%.
It is preferred that, above-mentioned steps 3) in vacuum tank (3) vacuum rate be 0.02Mpa.
It is preferred that, above-mentioned steps 3) in minipump the speed of exhaust for 20L it is per minute.
It is preferred that, above-mentioned steps 4) in watery hydrochloric acid concentration be 5%
Note:1 micron pore size (or following) glass is all needed before 1 all flushing deionized waters and saturated nacl aqueous solution use Glass Fibrous membrane filtration.
2 operating spaces should ensure that clean and certain humidity, and operating personnel should wear garment for clean room and be filled with and prevent clothes fiber from taking off Fall contaminated samples.
One section of silicone tube is connected after 3 elbow straws by peristaltic pump, liquid and the extract of floating are transferred to conical flask (2), pipeline need to be rinsed in advance.
4 micropore ceramics devices (4), using preceding rinsing well, should be cleaned by ultrasonic to remove the ore deposit of its adsorption after use Composition granule.
5 peristaltic pumps (6) and vavuum pump (7) should use the silicone tube of corresponding specification.
The art of this patent has advantages below compared with prior art:
1) the micro- plastics extraction process compression of deposit is reduced to a closing space by the present invention, it is not necessary to which special is dustless Laboratory, can complete dustless operation in common lab.
2) present invention does not have lower limit to limit extracted micro- plastics size in theory using without sieve extractive technique, improves Extractability.
3) present invention optimizes Density Separation device, improve micro- plastics extraction efficiency of fine grained deposit
4) extraction of micro- plastics and purification process are united completion by the present invention, improve efficiency.
5) the art of this patent device is simple, low cost, strong applicability.Beneficial to penetration and promotion.
Specific embodiment:
Following instance further describes details of the invention and effect:
Example 1
So that in the container (1) that the saturated nacl aqueous solution 2.5L additions after filtering have been rinsed, sealing stands 24 hours.Utilize Elbow straw and peristaltic pump are drawn 1/3 liquid and are entered in clean container (2), and ceramic device is inserted in container B after rinsing, B bottles Mouth is sealed with clean PE films, only by the connecting tube with Dewar bottle (3) of ceramic device.Opening minipump makes to be tieed up in C Negative pressure is held, solution is under atmospheric pressure through in ceramic wall inflow Dewar bottle (3) in (2).Solution is complete in treating conical flask (2) After portion is flowed into Dewar bottle (3), dilute hydrochloric acid solution is added to process 3-6 hours, then by deionized water rinsing 3 times, washing lotion crosses aperture 1 Micrometer glass fiber filter membrane.Sight glass filter membrane under 40 power microscopes, does not find any foreign matter.
Example 2
So that in the glass container (1) that the saturated nacl aqueous solution 2.5L additions after filtering have been rinsed, sealing stands 24h, on Layer liquid crosses 100 mesh sub-sieves, and with deionized water rinsing sieve surface after filtering, washing lotion crosses the micrometer glass fiber filter membrane of aperture 1. Sight glass filter membrane under 40 power microscopes, finds some red and blue celluloses, about 20 microns of diameter, length about 0.3-1mm.
Example 3
Take 10mg different-grain diameters polyethylene and PP GRANULES mix with 500g deposits after add glass container (1) In, adding 2.5L saturated nacl aqueous solutions and be sufficiently stirred for, sealing stands 24 hours.1/ is drawn using elbow straw and peristaltic pump 3 liquid enter in clean conical flask (2), and ceramic device is inserted in conical flask (2) after rinsing, and its bottleneck is sealed with new PE films, Only by the connecting tube with Dewar bottle (3) of ceramic device.Opening minipump makes to maintain negative pressure, taper in Dewar bottle (3) Solution is under atmospheric pressure through in ceramic wall inflow Dewar bottle (3) in bottle (2).After after solution emptying in (2), add 5% watery hydrochloric acid is processed 3 hours.Deionized water rinsing after addition filtering 3 times, washing lotion crosses the micrometer glass fiber filter membrane of aperture 1, claims Weight.
Example 4
Diameter 20um, length about 1mm colors are taken under scraping some fiber fines, microscope on polypropylene spun fabric purchased in market Bright-coloured monfil 20 is added in about 500g deposits, after mixture is extracted according to the step of example 3, counted under microscope, Fiber 17 is recycled, the rate of recovery is 85%.
Polyethylene (2mm) Polyethylene (300um) Polypropylene (2mm) Polypropylene (300um)
The rate of recovery (%) 100 99.2 100 99.7
Example 5
Beach sediment 500g is taken, any recovery mark is not added with, basis of microscopic observation after being extracted according to the step of example 3, It was found that white chips 1, blue cellulose 3, red fiber 1.
Brief description of the drawings:
Fig. 1 is micro- plastics extraction element schematic diagram in deposit.

Claims (9)

1. it is a kind of prevent sample be subject to environment in microfibre pollution extraction element, it is characterised in that including following part:
1) cylindrical glass container (1), the cylindrical glass container (1) mixes extraction for deposit with Density Separation solution The relatively low organic high molecular polymer particle of density;
2) conical flask (2), the conical flask (2) is connected with the other end of elbow straw (5), and the bottleneck of the conical flask is close Envelope;
3), there is closure Dewar bottle (3) at the opening of the Dewar bottle (3), by connecting tube and micropore ceramics device at sealing (4) internal to be connected, ceramic device (4) is placed in conical flask (2), and the Dewar bottle (3) is by another connecting tube on closure It is connected with vavuum pump;
4) elbow straw (5), the elbow straw is used to draw the floating particle in hydrostatic column (1), other end connection silicon Sebific duct simultaneously enters in conical flask (2) afterwards through peristaltic pump (6);
5) micropore ceramics device (4), top layer liquid and floating particle in cylindrical glass container (1) pass through elbow straw (5) After being transferred in conical flask (2), elbow straw, the liquid that the micropore ceramics device (4) is placed in conical flask (2) are removed In;
6) peristaltic pump (6) and minipump (7) should match with the connecting tube model for being used.
2. it is a kind of prevent sample be subject to environment in microfibre pollution extracting method, it is characterised in that comprise the following steps:
1) sediment sample 500g to be separated is taken, is put into cylindrical glass container (1), add 2.5L saturated nacl aqueous solutions After being sufficiently stirred for, sealing stands 6-48 hours;
2) elbow straw and peristaltic pump (6) are used by the interior liquid-covered floating object of cylindrical glass container (1) and 1/3 supernatant liquid It is transferred in conical flask (3);
3) micropore ceramics device (4) is inserted in conical flask (2), and is sealed, connect micropore ceramics device and Dewar bottle (3), opened Actuating miniature vavuum pump (7), the liquid in conical flask (2) is transferred in Dewar bottle (3);
4) 50ml watery hydrochloric acid rinses micropore ceramics device (4), by conical flask (2) sealing, treatment mixture 3-12 hours;
5) mixing liquid and flushing liquor are filtered in (2), and extract is retained on glass fiber filter.
3. a kind of extracting method for preventing sample to be subject to microfibre pollution in environment according to claim 2, its feature exists In a diameter of 12cm of the cylindrical glass container (1), is highly 35-40cm.
4. a kind of extracting method for preventing sample to be subject to microfibre pollution in environment according to claim 2, its feature exists The amount of the treatable deposit of institute is 0.25-1kg weight in wet bases in, the cylindrical glass container (1).
5. a kind of extracting method for preventing sample to be subject to microfibre pollution in environment according to claim 2, its feature exists In the step 2) in, wriggling pump discharge is 100-250r/min.
6. it is according to claim 2 it is a kind of prevent sample by microfibre pollution micro- plastics extraction element and its method, its Be characterised by, the step 3) in micropore ceramics device (4) aperture for 0.1 micron, porosity is 30%.
7. it is according to claim 2 it is a kind of prevent sample by microfibre pollution micro- plastics extraction element and its method, its Be characterised by, the step 3) in vacuum tank (3) vacuum be 0.02Mpa.
8. it is according to claim 2 it is a kind of prevent sample by microfibre pollution micro- plastics extraction element and its method, its Be characterised by, the step 3) in the minipump speed of exhaust be 20L/ point.
9. it is according to claim 2 it is a kind of prevent sample by microfibre pollution micro- plastics extraction element and its method, its Be characterised by, the step 4) in watery hydrochloric acid concentration be 5%.
CN201611100598.7A 2016-12-05 2016-12-05 A kind of micro- plastics extraction element and its method for preventing sample by microfibre pollution Pending CN106769356A (en)

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CN107364041A (en) * 2017-08-16 2017-11-21 河海大学 A kind of micro- flotation of Plastics separator and its application
CN107957490A (en) * 2017-11-17 2018-04-24 中国水产科学研究院黄海水产研究所 The experimental provision and application method of the micro- plastics ecological niche on-spot study of seawater
CN108593401A (en) * 2018-02-27 2018-09-28 浙江工业大学 The separation method of water environment or the micro- plastics of marine product sub-micron grade
CN109521181A (en) * 2018-10-29 2019-03-26 天津大学 The detection method of micro- plastics in a kind of beach sand
CN109540626A (en) * 2018-12-25 2019-03-29 福建师范大学 A kind of research device produced in water body, separate micro- plastics
CN111167190A (en) * 2020-02-21 2020-05-19 浙江树人学院(浙江树人大学) Integrated micro-plastic separation device for coastal sediments and micro-plastic collection method

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Cited By (8)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CN107364041A (en) * 2017-08-16 2017-11-21 河海大学 A kind of micro- flotation of Plastics separator and its application
CN107957490A (en) * 2017-11-17 2018-04-24 中国水产科学研究院黄海水产研究所 The experimental provision and application method of the micro- plastics ecological niche on-spot study of seawater
CN107957490B (en) * 2017-11-17 2020-04-03 中国水产科学研究院黄海水产研究所 Experimental device for seawater micro-plastic ecological niche in-situ research and using method
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CN109521181A (en) * 2018-10-29 2019-03-26 天津大学 The detection method of micro- plastics in a kind of beach sand
CN109540626A (en) * 2018-12-25 2019-03-29 福建师范大学 A kind of research device produced in water body, separate micro- plastics
CN109540626B (en) * 2018-12-25 2021-05-28 福建师范大学 Research device for preparing and separating micro-plastic in water body
CN111167190A (en) * 2020-02-21 2020-05-19 浙江树人学院(浙江树人大学) Integrated micro-plastic separation device for coastal sediments and micro-plastic collection method

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Application publication date: 20170531