Recycling method of amphiphilic surface-active pollutants in water

Abstract

The present disclosure provides a recycling method of amphiphilic surface-active pollutants in water, comprising: performing a polymerization reaction by illumination treatment on the amphiphilic surface-active pollutants in water to form a polymerization product; performing self-assembly on the polymerization product for aggregation to form a fluorescent material, and performing separation to obtain a recycled product. Through treatment of the amphiphilic surface-active pollutants by illumination, the present disclosure can realize the recycled utilization of the amphiphilic pollutants in the wastewater by one step of reaction, so that the amphiphilic surface-active pollutants can be converted into usable fluorescent materials, and the biological toxicity is greatly reduced. The obtained fluorescent material can be further used in the fields such as biological imaging as a recycled product, realizes detoxification of the pollutants and efficient conversion of organic carbon resources at the same time, provides a novel strategy for wastewater treatment and resource conversion, and achieves a win-win situation for economic benefits and environmental friendliness in the field of amphipathic organic pollution treatment and has a good application prospect.

Claims

1. A recycling method of amphiphilic surface-active pollutants in water, comprising: performing a polymerization reaction by illumination treatment on the amphiphilic surface-active pollutants in water to form a polymerization product; performing self-assembly on the polymerization product for aggregation to form a fluorescent material, and performing separation to obtain a recycled product.

2. The recycling method according to claim 1, wherein the wavelength for the illumination is 100 nm-1200 nm.

3. The recycling method according to claim 1, wherein the amphiphilic surface-active pollutants are selected from the group consisting of an anionic surfactant, a cationic surfactant, a nonionic surfactant, and a combination of at least two select therefrom.

4. The recycling method according to claim 1, wherein in the water, the volume ratio of the amphiphilic surface-active pollutants to the water is 0.0001%-99.9%.

5. The recycling method according to claim 3, wherein the anionic surfactant is selected from the group consisting of sodium dodecyl benzene sulfonate, sodium alcohol ether sulfate, ammonium alcohol ether sulfate, primary alcohol ethoxylate, sodium lauryl sulfate, olefin sulfonate, perfluorooctane sulfonate, and a combination of at least two selected therefrom.

6. The recycling method according to claim 3, wherein the cationic surfactant comprises an alkyl imidazoline surfactant and/or a quaternary ammonium surfactant.

7. The recycling method according to claim 3, wherein the nonionic surfactant is selected from the group consisting of alkylphenol ethoxylates, C.sub.1-C.sub.30 saturated fatty acid, fatty alcohol, fatty aldehyde and fatty amine, C.sub.1-C.sub.30 unsaturated fatty acid, fatty alcohol, fatty aldehyde and fatty amine, phthalate, and a combination of at least two selected therefrom.

8. The recycling method according to claim 1, wherein the illumination time is 0.5 h-48 h.

9. The recycling method according to claim 1, wherein the polymerization reaction further comprises: adding a photosensitizer to the water.

10. The recycling method according to claim 1, wherein the polymerization reaction is carried out under stirring.

11. The recycling method according to claim 10, wherein the stirring rate is 10 r/min-300 r/min.

12. The recycling method according to claim 1, wherein the pressure of self-assembly is selected from the group consisting of normal pressure, low pressure and high pressure.

13. The recycling method according to claim 12, wherein the low pressure has a pressure range of 0-−0.1 MPa.

14. The recycling method according to claim 12, wherein the high pressure has a pressure range of 2-50 MPa.

15. The recycling method according to claim 1, wherein the temperature of self-assembly is 10-200° C.

16. The recycling method according to claim 1, wherein the self-assembly is conducted under an atmosphere selected from the group consisting of nitrogen gas, oxygen gas, argon gas, ozone gas, helium gas, neon gas and air.

17. The recycling method according to claim 1, wherein the self-assembly is conducted under normal pressure, a temperature of 10° C.-50° C. and air atmosphere.

18. The recycling method according to claim 1, wherein the means of the separation is selected from the group consisting of extraction, chromatography, gel chromatography, physical standing, and a combination of at least two selected therefrom.

19. The recycling method according to claim 1, wherein the means of the separation is physical standing; the time of physical standing is 2-10 days.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 is an electron micrograph of the recycled product obtained in Example 1 of the present disclosure (with a scale of 10 nm).

(2) FIG. 2A is a view showing the recycled product obtained in Example 1 of the present disclosure observed under indoor sunlight.

(3) FIG. 2B is a view showing the recycled product obtained in Example 1 of the disclosure observed under an ultraviolet lamp.

(4) FIG. 3 is a bar graph of the cytotoxicity test of the recycled product obtained in Example 1 of the present disclosure.

(5) FIG. 4 is a view showing a use of the recycled product obtained in Example 1 of the present disclosure in cell imaging.

DETAILED DESCRIPTION

(6) The technical solution of the present disclosure is further illustrated by the specific embodiments below. Those skilled in the art shall understand that the examples are set forth to assist in understanding the present disclosure and should not be regarded as specific limitations to the present disclosure.

Example 1

(7) In this example, a wastewater containing nonanoic acid as a pollutant was treated by the following steps:

(8) a mixture of nonanoic acid (NA) and water in a volume ratio of 1% was sonicated for 10 min, magnetically stirred for 10 min at 200 r/min, and irradiated for 16 h at 770 nm, self-assembled and aggregated at 25° C. at normal pressure under air atmosphere, followed by physical standing for 8 days, and a recycled product was obtained. According to mass spectrometry, the recycled conversion rate of nonanoic acid in the wastewater reached 73.8%.

Example 2

(9) In this example, a wastewater containing dibutyl phthalate as a pollutant was treated by the following steps:

(10) a mixture of dibutyl phthalate and water in a volume ratio of 2% was sonicated for 10 min, magnetically stirred for 10 min at 300 r/min, and irradiated for 0.5 h at 1200 nm, self-assembled and aggregated at 25° C. at normal pressure under air atmosphere, followed by physical standing for 2 days, and a recycled product was obtained. According to mass spectrometry, the recycled conversion rate of dibutyl phthalate in the wastewater reached 62.4%.

Example 3

(11) In this example, a wastewater containing primary alcohol ethoxylate and sodium lauryl sulfate as pollutants was treated by the following steps:

(12) a mixture of primary alcohol ethoxylate, sodium lauryl sulfate, and water in a ratio of the volume of primary alcohol ethoxylate and sodium lauryl sulfate to the volume of the water of 1% was sonicated for 10 min, magnetically stirred for 10 min at 10 r/min, and irradiated for 48 h at 100 nm, self-assembled and aggregated at 25° C. at normal pressure under air atmosphere, followed by separation and purification with a silica gel plate, and a recycled product was obtained.

(13) According to mass spectrometry, the recycled conversion rate of primary alcohol ethoxylate and sodium lauryl sulfate in the wastewater reached 59.3%.

Example 4

(14) In this example, a wastewater containing α-olefin sulfonate and sodium alcohol ether sulfate as pollutants was treated by the following steps:

(15) a mixture of α-olefin sulfonate, sodium alcohol ether sulfate and water in a ratio of the volume of α-olefin sulfonate and sodium alcohol ether sulfate to the volume of the water of 1% was sonicated for 10 min, magnetically stirred for 10 min at 200 r/min, and irradiated for 10 h at 700 nm, self-assembled and aggregated at 25° C. at normal pressure under air atmosphere, followed by separation and purification with a silica gel plate, and a recycled product was obtained. According to mass spectrometry, the recycled conversion rate of α-olefin sulfonate and sodium alcohol ether sulfate reached 61.7%.

Example 5

(16) In this example, a wastewater containing octanoic acid and sodium alcohol ether sulfate as pollutants was treated by the following steps:

(17) benzophenone as a photosensitizer was added to a mixture of octanoic acid, sodium alcohol ether sulfate and water in a ratio of the volume of octanoic acid and sodium alcohol ether sulfate to the volume of the water of 86.8%. The mixture was sonicated for 10 min, magnetically stirred for 10 min at 200 r/min, and irradiated for 10 h at 700 nm, self-assembled and aggregated at 40° C. at normal pressure under air atmosphere, followed by separation and purification with a silica gel plate to obtain fluorescent carbon nanoparticles as a recycled product. According to mass spectrometry, the recycled conversion rate of octanoic acid and sodium alcohol ether sulfate reached 45.8%.

Example 6

(18) In this example, a wastewater containing 2-alkenyl n-hexanoic acid as a pollutant was treated by the following steps:

(19) a mixture of 2-alkenyl n-hexanoic acid and water in a volume ratio of 0.005% was irradiated for 14 h at 800 nm, then self-assembled and aggregated at 25° C. at normal pressure under air atmosphere, followed by separation and purification with a silica gel plate to obtain fluorescent carbon nanoparticles as a recycled product. According to mass spectrometry, the recycled conversion rate of 2-alkenyl n-hexanoic acid in the wastewater reached 57.6%.

Comparison Example 1

(20) The only difference from Example 1 is that, in the present comparison example, no treatment of wastewater by illumination at 700 nm was conducted.

(21) This comparison example failed to process wastewater to obtain recycled products, and failed to realize recycled utilization.

(22) Performance Tests of Recycled Products:

(23) The recycled product obtained in Example 1 was observed under electron microscope, indoor sunlight, and ultraviolet light, specifically as shown in FIG. 1, FIG. 2A and FIG. 2B. As can be seen from FIG. 1, it is found through electron microscopy that the fluorescent carbon nanoparticles have a spheroidal external form and a particle diameter of less than 10 nm. FIG. 2A illustrates that the fluorescent carbon nanomaterial is dispersed in the solvent and shows yellow under indoor sunlight, and FIG. 2B illustrates that it shows bright blue fluorescence under ultraviolet light irradiation.

(24) The recycled product prepared in Example 1 was subjected to cytotoxicity test (with results shown in FIG. 3) and cell imaging test (with a result shown in FIG. 4):

(25) The cytotoxicities of the obtained recycled product in the remaining NA solution and the original NA were evaluated by MTT (3-(4,5-dimethyl thiazol-2-yl)-2,5-diphenyltetrazolium bromide) assay. Human lung cancer cell line A549 cells were grown in DMEM medium supplemented with 10% (v/v) of fetal bovine serum (FBS) and 1% of penicillin streptomycin. A549 was first incubated at 37° C. for 24 hours with a density of 5000 cells per well. After being washed with phosphate buffered saline (PBS, pH=7.4), A549 cells were incubated together with 200 μL of medium having various concentrations for 24 hours (15 μM, 30 μM, 60 μM, 120 μM, 240 μM, 480 μM, 960 μM, 1920 μM, 3840 μM, 7680 μM, 15360 μM). Three sets of parallel replicates were prepared for each concentration. Then, the medium was removed and replaced with 20 μL of MTT solution (5 mg/mL). A549 cells were further incubated for 3 hours. The medium having MTT was removed and replaced with 100 μL of DMSO. The plate was then shaken for 10 minutes. To assess cell viability, the optical density of the mixture at 492 nm was measured by an enzyme-linked immunosorbent assay spectrophotometer (infinite F90). For labeling, A549 cells were incubated at 37° C. for 24 hours in a cell culture dish with glass bottom at a density of 5000 cells/well and then mixed with prepared FCNs samples. After incubating for 3 hours at a concentration of 480 μM, A549 cells were thoroughly washed three times with PBS (pH=7.4), and then fixed with 1 mL of paraformaldehyde (1%, v/v). The control group was carried out in the absence of FCN. The cell culture dish with glass bottom was covered with a tin foil until cell images were obtained by fluorescence microscopy under excitation at 408 nm, 488 nm and 561 nm.

(26) According to the toxicity test, at low concentration (15-240 μM), nonanoic acid and the recycled product have almost no effect on cell viability; when the concentration is 480-3840 μM, the recycled product can promote cell growth more than nonanoic acid; when the concentration is greater than 3840 μM, nonanoic acid shows significant toxicity to the cells, while the recycled product is still not significantly toxic to the cells. In summary, the conversion of nonanoic acid to a recycled product reduces the cytotoxicity to the organism. The above toxicity tests demonstrate that the treatment method provided by the present disclosure can greatly reduce the toxicity of amphiphilic surface-active pollutants in wastewater.

(27) It can be seen from the cell imaging test that the recycled product obtained by the recycling treatment of the present disclosure can be well applied to cell imaging and can be fully applicable to the bio-imaging field.

(28) The applicant declares that the recycling method of amphiphilic surface-active pollutants in water is illustrated by the above examples. However, the present disclosure is not limited to the above process steps, that is, it does not mean that the present disclosure must rely on the above process steps to be implemented. It will be apparent to those skilled in the art that any modifications of the present disclosure, equivalent substitutions of the materials for the product of the present disclosure, and additions of auxiliary ingredients, selections of the specific means and the like, are all within the protection and disclosure scopes of the present disclosure.