CN113249370B - Preparation method of bio-based nano material and method for treating organic dye in wastewater - Google Patents
Preparation method of bio-based nano material and method for treating organic dye in wastewater Download PDFInfo
- Publication number
- CN113249370B CN113249370B CN202110509146.9A CN202110509146A CN113249370B CN 113249370 B CN113249370 B CN 113249370B CN 202110509146 A CN202110509146 A CN 202110509146A CN 113249370 B CN113249370 B CN 113249370B
- Authority
- CN
- China
- Prior art keywords
- bio
- hydrocarbon degrading
- wastewater
- nano material
- adsorption
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- C—CHEMISTRY; METALLURGY
- C12—BIOCHEMISTRY; BEER; SPIRITS; WINE; VINEGAR; MICROBIOLOGY; ENZYMOLOGY; MUTATION OR GENETIC ENGINEERING
- C12N—MICROORGANISMS OR ENZYMES; COMPOSITIONS THEREOF; PROPAGATING, PRESERVING, OR MAINTAINING MICROORGANISMS; MUTATION OR GENETIC ENGINEERING; CULTURE MEDIA
- C12N11/00—Carrier-bound or immobilised enzymes; Carrier-bound or immobilised microbial cells; Preparation thereof
- C12N11/14—Enzymes or microbial cells immobilised on or in an inorganic carrier
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y30/00—Nanotechnology for materials or surface science, e.g. nanocomposites
-
- B—PERFORMING OPERATIONS; TRANSPORTING
- B82—NANOTECHNOLOGY
- B82Y—SPECIFIC USES OR APPLICATIONS OF NANOSTRUCTURES; MEASUREMENT OR ANALYSIS OF NANOSTRUCTURES; MANUFACTURE OR TREATMENT OF NANOSTRUCTURES
- B82Y40/00—Manufacture or treatment of nanostructures
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F3/00—Biological treatment of water, waste water, or sewage
- C02F3/34—Biological treatment of water, waste water, or sewage characterised by the microorganisms used
-
- C—CHEMISTRY; METALLURGY
- C02—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F—TREATMENT OF WATER, WASTE WATER, SEWAGE, OR SLUDGE
- C02F2101/00—Nature of the contaminant
- C02F2101/30—Organic compounds
- C02F2101/308—Dyes; Colorants; Fluorescent agents
Landscapes
- Chemical & Material Sciences (AREA)
- Engineering & Computer Science (AREA)
- Life Sciences & Earth Sciences (AREA)
- Nanotechnology (AREA)
- Microbiology (AREA)
- Organic Chemistry (AREA)
- Genetics & Genomics (AREA)
- Wood Science & Technology (AREA)
- Crystallography & Structural Chemistry (AREA)
- General Physics & Mathematics (AREA)
- Health & Medical Sciences (AREA)
- Bioinformatics & Cheminformatics (AREA)
- Condensed Matter Physics & Semiconductors (AREA)
- Physics & Mathematics (AREA)
- Zoology (AREA)
- Biotechnology (AREA)
- Biomedical Technology (AREA)
- Biochemistry (AREA)
- General Engineering & Computer Science (AREA)
- General Health & Medical Sciences (AREA)
- Water Supply & Treatment (AREA)
- Composite Materials (AREA)
- Hydrology & Water Resources (AREA)
- Inorganic Chemistry (AREA)
- Materials Engineering (AREA)
- Environmental & Geological Engineering (AREA)
- Biodiversity & Conservation Biology (AREA)
- Manufacturing & Machinery (AREA)
- Solid-Sorbent Or Filter-Aiding Compositions (AREA)
- Micro-Organisms Or Cultivation Processes Thereof (AREA)
- Water Treatment By Sorption (AREA)
Abstract
The invention discloses a preparation method of a bio-based nano material and a method for treating organic dye in wastewater by using the bio-based nano material, belonging to the technical field of wastewater treatment. The preparation method of the bio-based nano material comprises the following steps: obtaining a suspension of hydrocarbon-degrading bacteria for modification comprising: providing a single hydrocarbon degrading bacterial strain, culturing the single hydrocarbon degrading bacterial strain in an enrichment medium to obtain thalli in a logarithmic growth phase, washing the thalli by using sterile water after centrifugal treatment to obtain a suspension of the modified hydrocarbon degrading bacterial strain, wherein the OD of the suspension of the modified hydrocarbon degrading bacterial strain is 600 The value is 0.5 to 2.0; adding the nano material into the hydrocarbon degrading bacteria suspension liquid for modification under the condition of stirring, wherein the mass ratio of the nano material to the hydrocarbon degrading bacteria suspension liquid is 1:1-1:5, and performing vacuum freeze drying to obtain the bio-based nano material. The bio-based nano material can effectively adsorb organic dyes.
Description
Technical Field
The invention relates to the technical field of wastewater treatment, in particular to a preparation method of a bio-based nano material and a method for treating organic dye in wastewater by using the bio-based nano material.
Background
Many industries such as textile, paper, cosmetics, rubber, pesticides, leather, etc. produce waste water containing organic dyes. Organic dyes pose a great threat to aquatic systems due to their carcinogenic, teratogenic, and mutagenic effects on living organisms.
Therefore, a green and effective method for removing organic dyes is needed.
Disclosure of Invention
In order to solve at least one of the above problems in the prior art, embodiments of the present invention provide a method for preparing a bio-based nanomaterial and a method for treating an organic dye in wastewater using the bio-based nanomaterial.
The bio-based nano material prepared according to the embodiment of the invention has a honeycomb structure and a plurality of small holes, bacteria are attached to the surface of the nano material, the nano material has a larger specific surface area, and the effective adsorption sites of organic dyes are increased. Thus, the embodiment of the invention can more effectively treat the organic dye in the wastewater and relieve the harm of the organic dye in the wastewater to organisms.
According to an aspect of the present invention, there is provided a method for preparing a bio-based nanomaterial, comprising: obtaining a suspension of hydrocarbon degrading bacteria for modification comprising the steps of: providing a single hydrocarbon degrading bacterial strain, culturing the single hydrocarbon degrading bacterial strain in an enrichment medium to obtain thallus in a logarithmic growth phase, suspending the thallus in sterile water after centrifugation and washing by using the sterile water to obtain a hydrocarbon degrading bacterial suspension for modification, wherein the density of the bacterial suspension is determined by measuring the absorbance value at 600nm, and the OD of the hydrocarbon degrading bacterial suspension for modification 600 The value is 0.5 to 2.0; stirring the nano materialAdding the modified nano material into a hydrocarbon degrading bacteria suspension, wherein the mass ratio of the nano material to the hydrocarbon degrading bacteria suspension is 1:1-1:5, and then carrying out vacuum freeze drying to obtain the bio-based nano material.
According to another aspect of the present invention, there is provided a method for treating an organic dye in wastewater by using a bio-based nanomaterial, comprising: providing a bio-based nanomaterial obtained according to the method of preparation described in any one of the preceding embodiments; standing the wastewater for a preset time, and then pretreating the wastewater by using a filter; adding the bio-based nano material into the pretreated wastewater, and adsorbing the organic dye under the conditions that the temperature is 15-45 ℃ and the rotating speed of a shaking table is 80-150 rpm.
The bio-based nano material in the embodiment of the disclosure has a larger specific surface area, and adsorption sites of organic dyes are increased, so that the bio-based nano material can be used for efficiently and environmentally treating the organic dyes in a water phase, thereby alleviating the harm of the organic dyes to organisms.
Other objects and advantages of the present disclosure will become apparent from the following description of the embodiments of the present disclosure, which is made with reference to the accompanying drawings, and can assist in a comprehensive understanding of the present disclosure.
Drawings
These and/or other aspects and advantages of the present invention will become apparent and readily appreciated from the following description of the preferred embodiments, taken in conjunction with the accompanying drawings of which:
fig. 1 illustrates a method for preparing bio-based nanomaterial and a method for treating organic dye in wastewater according to an embodiment of the present invention;
fig. 2 illustrates a method for preparing a bio-based nanomaterial and a method for treating an organic dye in wastewater according to another embodiment of the present invention;
FIG. 3a is a TEM image of hydrocarbon degrading bacteria YD-Y according to an embodiment of the invention;
FIG. 3b is a TEM image of hydrocarbon degrading bacteria YD-LP in accordance with another embodiment of the invention;
FIG. 4a is a phylogenetic tree of hydrocarbon degrading bacteria YD-Y plotted based on a neighbor method according to an embodiment of the invention;
FIG. 4b is a phylogenetic relation tree of hydrocarbon degrading bacteria YD-LP plotted based on a neighbor method according to another embodiment of the invention;
FIG. 5a is a scanning electron microscope image of hydrocarbon degrading bacteria YD-Y modified nano-activated carbon according to an embodiment of the invention;
FIG. 5b is Hydrocarbon degrading bacteria YD-LP modified magnetic clustered nano Fe according to an embodiment of the invention 3 O 4 Scanning electron microscope images of (a);
FIG. 6a shows the adsorption effect of hydrocarbon degrading bacteria YD-Y modified nano activated carbon on Congo red of different concentrations in wastewater according to an embodiment of the invention;
FIG. 6b shows Hydrocarbon degrading bacteria YD-LP modified magnetic clustered nano Fe according to another embodiment of the invention 3 O 4 Adsorption effect on Congo red with different concentrations in the wastewater;
FIG. 7a shows the adsorption effect of different amounts of hydrocarbon degrading bacteria YD-Y modified nano-activated carbon on Congo red in wastewater according to an embodiment of the invention;
FIG. 7b shows different Hydrocarbon degrading bacteria YD-LP modifying magnetic clustered nano Fe according to another embodiment of the invention 3 O 4 The adsorption effect of the dosage on Congo red in the wastewater;
FIG. 8a shows the adsorption effect of hydrocarbon degrading bacteria YD-Y modified nano activated carbon on Congo red in wastewater under different initial wastewater pH values according to an embodiment of the invention;
FIG. 8b shows hydrocarbon degrading bacteria YD-LP modifying magnetic clustered nano Fe under different initial pH of wastewater according to another embodiment of the present invention 3 O 4 The adsorption effect on Congo red in the wastewater.
Detailed Description
The technical scheme of the invention is further specifically described by the following embodiments and the accompanying drawings. In the specification, the same or similar reference numerals denote the same or similar components. The following description of the embodiments of the present invention with reference to the accompanying drawings is intended to explain the general inventive concept of the present invention and should not be construed as limiting the invention.
According to the general concept of the present invention, there is provided a method of preparing a bio-based nanomaterial. As shown in fig. 1 and 2, the preparation method of the bio-based nanomaterial comprises the following steps: obtaining a suspension of hydrocarbon degrading bacteria for modification comprising the steps of: providing a single hydrocarbon degrading bacterial strain, culturing the single hydrocarbon degrading bacterial strain in an enrichment medium to obtain thallus in a logarithmic growth phase, suspending the thallus in sterile water after centrifugation and washing by using the sterile water to obtain a hydrocarbon degrading bacterial suspension for modification, wherein the density of the bacterial suspension is determined by measuring the absorbance value at 600nm, and the OD of the hydrocarbon degrading bacterial suspension for modification 600 The value is 0.5 to 2.0; adding the nano material into the hydrocarbon degrading bacteria suspension for modification under the condition of stirring, wherein the mass ratio of the nano material to the hydrocarbon degrading bacteria suspension is 1:1-1:5 (preferably 1:2-1:4, more preferably 1:3), and then carrying out vacuum freeze drying to obtain the bio-based nano material. Accordingly, the prepared bio-based nanomaterial of the embodiment of the present invention has a honeycomb structure and increased adsorption sites of organic dyes, so that organic dyes in an aqueous phase can be efficiently treated.
In an example, as shown in fig. 1 and 2, obtaining a suspension of hydrocarbon degrading bacteria for modification comprises the steps of: obtaining a surface seawater or surface sediment sample from an offshore area polluted by petroleum hydrocarbon; adding surface seawater or surface sediment sample into an acclimation culture medium which takes crude oil as a sole carbon source for acclimation, wherein the acclimation culture medium is autoclaved natural seawater containing crude oil with the mass fraction of 0.1-2% (preferably 0.5-1.5%, more preferably 0.8-1.0%); after acclimatization for a preset time, obtaining a single hydrocarbon degrading bacterial strain by a solid plate trisection method; culturing a single hydrocarbon degrading bacterial strain in an enrichment medium to obtain thalli in a logarithmic growth phase, washing the thalli by using sterile water after centrifugal treatment, and suspending the thalli in the sterile water to obtain a hydrocarbon degrading bacterial suspension for modification. Determination of the Density of a bacterial suspension by measuring the absorbance value at 600nmFor example OD of said suspensions of hydrocarbon degrading bacteria for modification 600 Values of 0.5 to 2.0, preferably 1.0 to 1.5.
In embodiments, the enrichment medium comprises 1-10g/L (preferably 3-8g/L, more preferably 5 g/L) of inorganic salts, 5-20g/L (preferably 6-16g/L, more preferably 10 g/L) of proteins, and 1-6g/L (preferably 2-4g/L, more preferably 3 g/L) of muscle tissue extract. In an example, the inorganic salt includes any one of sodium chloride, potassium chloride, sodium nitrate, potassium nitrate, sodium sulfate, and potassium sulfate, or any combination thereof. In one example, the protein includes any one of peptone, fish protein peptide, egg white protein and whey protein, or any combination thereof. In an example, the muscle tissue extract includes any one of beef extract, pork extract, chicken extract, and beef extract, or any combination thereof.
In an embodiment, the acclimation is performed for a predetermined time period of three to five cycles or more, wherein each cycle comprises 7 days.
In an embodiment, the hydrocarbon degrading bacteria are petroleum hydrocarbon degrading bacteria. In one example, the petroleum hydrocarbon degrading bacteria include any one of or a combination of micro-Bacillus (Exiguobacterium sp.) and Bacillus cereus. However, it will be apparent to those skilled in the art that embodiments of the present disclosure are not limited to this particular embodiment and that other suitable hydrocarbon degrading bacteria may be employed.
In an embodiment, the nanomaterial comprises activated carbon and magnetic iron tetroxide (Fe) in clusters 3 O 4 ) Any one of or a combination of materials. However, it will be clear to those skilled in the art that embodiments of the present invention are not limited to this particular embodiment, and that other suitable nanomaterials may also be employed.
In an embodiment, the method further comprises pretreating the activated carbon to remove impurities therein and form a more small pore structure before adding the activated carbon to the suspension of hydrocarbon degrading bacteria for modification. In an embodiment, as shown in fig. 1, the pretreated activated carbon comprises: grinding the activated carbon to 80-120 mesh (preferably 100 mesh); soaking with acid liquor overnight to remove impurities, washing with sterile ultrapure water to neutrality, centrifuging, removing supernatant and retaining precipitate; the precipitate is dried in a thermostatted drying cabinet at 40-80 c, preferably 60 c. In one example, the acid solution includes any one or a combination of hydrochloric acid, nitric acid, and sulfuric acid. In one example, a nitric acid soak of 0.7-0.8mol/L (preferably 0.72 mol/L) is used overnight. In one example, the precipitate is dried in a constant temperature drying oven for 6-24 hours (preferably 12-18 hours).
In the examples, clustered ferroferric oxide was prepared by a one-step solvothermal process, as shown in fig. 2. Adding 0.5-2.0g (preferably 0.99-1.65g, more preferably 1.32 g) FeCl into 60-100mL (preferably 80 mL) of ethylene glycol 3 Stirring, adding 2.7-4.5g (preferably 3.6 g) polyacrylic acid, and stirring to dissolve completely. And then 15 to 35mL (preferably 20 mL) of hydroxylamine is added and stirred to be completely dissolved, the solution is transferred to an autoclave (preferably, an autoclave with a polytetrafluoroethylene lining), the solution is treated with a water bath at 160 to 250 ℃ (preferably 200 to 250 ℃, more preferably 230 ℃) for 1 to 5 hours (preferably 1.5 to 3 hours, more preferably 2 hours), the precipitate is retained after the centrifugal treatment and washed (for example, three or more times) with anhydrous ethanol, and the precipitate is dried under vacuum conditions of 40 to 80 ℃ (preferably 60 ℃) for 12 to 36 hours (preferably 24 hours) to obtain cluster nano ferroferric oxide.
According to the general inventive concept, there is also provided a method of treating an organic dye in wastewater with bio-based nanomaterial. As shown in fig. 1 and 2, the method includes: providing a bio-based nanomaterial obtained according to the method of preparation of any one of the preceding embodiments; standing the wastewater for a preset time, and then pretreating the wastewater by using a filter; adding the bio-based nano material into the pretreated wastewater, and performing adsorption of the organic dye under the conditions that the temperature is 15-45 ℃ (preferably 20-30 ℃, more preferably 25 ℃) and the rotating speed of a shaking table is 80-150rpm (preferably 100-120 rpm). In one example, the adsorption of the organic dye is carried out in a shaker at a pH of 4 to 11, preferably 5 to 7. For example, 0.1mol/L NaOH or HCl may be used to adjust the pH. In the examples, the wastewater was allowed to stand for 1 to 2 days and then filtered to primarily remove impurities in the wastewater.
In embodiments, the organic dye comprises any one of congo red, malachite green, methyl violet, crystal violet, and the like, or any combination thereof.
The following detailed description will be given with specific examples. It will be appreciated by persons skilled in the art that the present invention is not limited to the specific embodiments described, but that reasonable modifications are possible in light of the teaching of the present invention.
Screening and isolation of hydrocarbon degrading bacteria
Obtaining a surface seawater or surface sediment sample from an offshore area polluted by petroleum hydrocarbon; adding surface seawater or surface sediment samples into an acclimation culture medium which takes crude oil as a unique carbon source for acclimation, wherein the acclimation culture medium is autoclaved natural seawater containing 0.1-2% of crude oil by mass fraction; after acclimation for four cycles, each 7 days, a single hydrocarbon degrading bacterial strain was obtained by solid plate trisection.
Characterization and identification of strains
The hydrocarbon degrading bacteria single strain obtained above was cultured to logarithmic phase in an enrichment medium, centrifuged at 6000g for 10 minutes, and then washed several times with sterile water. The cells were fixed at 4 ℃ for 1 hour using 2.5% by mass of glutaraldehyde. The fixed cells were then washed several times with 50mM phosphate buffered saline (PBS, pH = 7.0). In PBS (OD) 600 = 1.5), fishing out the thalli from the suspension by using a special copper net for a transmission electron microscope, and irradiating the copper net under an infrared lamp for 15 minutes. The dried sample was scanned using a Transmission Electron Microscope (TEM) (JEM-2100, JEOL, japan). The results are shown in FIGS. 3a and 3 b. As can be seen from FIG. 3a, the strain YD-Y was 500nm in width and 1.5-2 μm in length and without flagella. As can be seen from FIG. 3b, the width of the strain YD-LP is 400-500 nm and the length is 1.5-2 μm.
The centrifugally washed bacteria are sent to Shanghai Meiji biological medicine science and technology limited for sequencing. After the splice sequence was obtained, the DNA sequence alignment was done in BLAST on the NCBI website. Phylogenetic trees were constructed using MEGA software (version X) and using the adjacency algorithm (bootstrap number = 1000). The results are shown in FIGS. 4a and 4 b. As shown in FIG. 4a, the strain YD-Y has a high similarity to the sequence of Microbacterium (Exiguobacterium sp.) BDH26 (KF 933621.1, 99.31%), so the bacterium was identified as Microbacterium. As shown in fig. 4b, the strain YD-LP has a high similarity to the sequence of bacillus cereus DPBS059 (mg452794., 100%), so this strain is considered as bacillus cereus.
Preparation of bio-based nano material
1) Preparation of hydrocarbon degrading bacteria modified active carbon
Pretreating the activated carbon: 6g of Activated Carbon (AC) was ground at 100 mesh and soaked with 0.72mol/L nitric acid for 24 hours (h), then washed to neutrality with ultrapure water, centrifuged to remove the supernatant to retain the precipitate, and the precipitate was dried in an electrothermal constant temperature drying oven at 100 ℃ for 12 hours.
Resuspending hydrocarbon degrading bacteria in sterile water to obtain OD 600 The bacterial suspension of the =1 is added into the pretreated activated carbon according to the mass ratio of 1:1-1:5 under the condition of stirring. The activated carbon and bacterial suspension were sealed in a beaker and dried in a vacuum freeze dryer for 12 hours to obtain hydrocarbon degrading bacteria-modified activated carbon.
2) Hydrocarbon degrading bacteria modified magnetic cluster nano Fe 3 O 4 Preparation of (2)
Magnetic cluster-shaped nano Fe prepared by one-step solvothermal method 3 O 4 . Specifically, 1.0g FeCl was added to 80mL ethylene glycol 3 And 3.5g of polyacrylic acid, which was completely dissolved by stirring, and then 28mL of hydroxylamine was added and completely dissolved by stirring, and then the mixture was quickly transferred to a 100mL autoclave lined with polytetrafluoroethylene and subjected to a water bath treatment at 160 ℃ for 3 hours. Then centrifuging and collecting the precipitate, washing the precipitate with absolute ethyl alcohol for three times, and drying the precipitate in vacuum at 60 ℃ for 24 hours to obtain the magnetic cluster-shaped nano Fe 3 O 4 。
Resuspending hydrocarbon-degrading bacteriaObtaining OD in sterile water 600 =1 bacterial suspension, then adding the bacterial suspension to the magnetic cluster nano-Fe according to 1:1-1:5 under stirring 3 O 4 Drying in a vacuum freeze dryer to obtain the hydrocarbon degrading bacteria modified magnetic cluster nano Fe 3 O 4 。
Surface structure analysis of bio-based nanomaterials
The adsorbent (hydrocarbon degrading bacteria modified activated carbon and hydrocarbon degrading bacteria modified magnetic cluster nano Fe) was analyzed under the condition of 5kV by using a scanning electron microscope (JEOL JSM-7610F, japan) 3 O 4 ) The surface structure of (1). The results are shown in fig. 5a and 5 b.
As shown in fig. 5a and 5b, the bio-based nanomaterial has a honeycomb structure and small pores, the surface is filled with bacteria, it has a large specific surface area, and adsorption sites for dyes or contaminants are increased, thereby achieving a significant increase in adsorption capacity and an increase in specific surface area.
Organic dye in water phase treated by bio-based nano material
The organic dye Congo red in the water phase is treated by utilizing a bio-based nano material. A wastewater sample of 5kg was obtained from wastewater discharged from a certain plant, and after standing the sample for 1 day, large particulate impurities were filtered off using a filter and pH was adjusted =7. 5mg of bio-based nanomaterial was added to a 40mL sample of wastewater in a container and the container was placed on a shaker at 100rpm at 25 ℃ until adsorption equilibrium was reached. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer.
Adsorption characteristic of bio-based nano material to organic dye in water phase
(1) Effect of Congo Red initial concentration
5mg of hydrocarbon degrading bacteria modified activated carbon (referred to as modified activated carbon) and 40mL of Congo red wastewater at different concentrations (20, 40, 60, 80, 100 mg/L) were mixed in a 50mL bottle. The vial was placed on a shaker at 100rpm at room temperature (25 ℃) until equilibrium adsorption was reached. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer. Furthermore, a control experiment was performed using activated carbon instead of modified activated carbon. The results are shown in FIG. 6 a.
As shown in FIG. 6a, the adsorption capacity (Q) of the modified activated carbon e ) Basically, the tendency is first to increase and then to decrease. As the initial concentration of Congo red increased from 20mg/L to 80mg/L, the adsorption capacity of the modified activated carbon increased from 155.8mg/g to 234.6mg/g, and the adsorption removal rate (AR) peaked at 80mg/L (97.4%). The adsorption capacity (or adsorption removal rate) of activated carbon basically exhibits a similar tendency to that of modified activated carbon, except that the adsorption capacity of activated carbon is much lower than that of modified activated carbon. For example, at 80mg/L, the maximum adsorption capacity of activated carbon is only 36.7mg/g. Therefore, the optimal concentration of the solution containing the Congo red removed by the modified activated carbon is 80mg/L.
Magnetic cluster nano Fe modified by 5mg of hydrocarbon degrading bacteria in a 50mL bottle 3 O 4 (referred to as modified Fe) 3 O 4 ) And 40mL of Congo red wastewater at various concentrations (20, 40, 60, 80, 100, 120, and 140 mg/L). The vial was placed on a shaker at 100rpm at room temperature (25 ℃) until equilibrium adsorption was reached. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer. And, using Fe 3 O 4 Substituted for modified Fe 3 O 4 Control experiments were performed. The results are shown in FIG. 6 b.
Modified Fe as shown in FIG. 6b 3 O 4 The adsorption capacity of (a) tends to increase first and then decrease. Modified Fe as the initial concentration of Congo Red increased from 20mg/L to 100mg/L 3 O 4 The adsorption capacity of (A) was increased from 59.8mg/g to 320.2mg/g, and the adsorption removal rate (AR) reached a peak of 40.0% at 100mg/L. Fe 3 O 4 Substantially exhibits an adsorption capacity (or adsorption removal rate) with respect to modified Fe 3 O 4 Similar trend, only Fe 3 O 4 Has an adsorption capacity far lower than that of modified Fe 3 O 4 The adsorption capacity of (c). For example, at 120mg/L, fe 3 O 4 The maximum adsorption capacity of (2) is only 140.0mg/g. Thus, modified Fe 3 O 4 The optimal concentration for removing the solution containing congo red is 100mg/L.
(2) Influence of the amount of adsorbent
1, 3, 5, 10, 15, 20 and 30mg of hydrocarbon degrading bacteria modified activated carbon (referred to as modified activated carbon) and 80mg/L of 40mL of Congo red wastewater were added to a 50mL bottle and mixed. The vial was placed on a shaker at 100rpm at room temperature (25 ℃) until equilibrium adsorption was reached. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer. Furthermore, a control experiment was performed using activated carbon instead of modified activated carbon. The results are shown in FIG. 7 a.
As shown in fig. 7a, the adsorption capacity of the modified activated carbon tends to increase first and then decrease. At the dosage of 5mg of modified activated carbon, the adsorption capacity reaches the peak value of 221.5mg/g, and the adsorption removal rate reaches the peak value of 95.1 percent. The adsorption capacity (or adsorption removal rate) of activated carbon shows a similar tendency to that of modified activated carbon, except that the adsorption capacity of activated carbon is much lower than that of modified activated carbon. For example, at a dosage of 5mg of activated carbon, the adsorption capacity of activated carbon reaches a peak value of only 59.8mg/g. Therefore, the modified activated carbon of the present invention can achieve higher adsorption efficiency with less adsorbent usage.
Adding 3, 5, 8, 10, 20 and 30mg of hydrocarbon degrading bacteria modified magnetic cluster-shaped nano Fe into a 50mL bottle 3 O 4 (referred to as modified Fe) 3 O 4 ) And 80mg/L of 40mL Congo red wastewater. The vial was placed on a shaker at 100rpm at room temperature (25 ℃) until adsorption equilibrium was reached. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer. And, using Fe 3 O 4 Substituted for modified Fe 3 O 4 Control experiments were performed. The results are shown in FIG. 7 b.
Modified Fe as shown in FIG. 7b 3 O 4 The adsorption capacity of (a) is substantially in a tendency of increasing first and then decreasing. Modified Fe at 5mg 3 O 4 The adsorption capacity of the adsorbent reaches a peak value of 320.1mg/g. The adsorption removal rate of congo red increases with the increase of the dosage of the adsorbent, and reaches the maximum value when the dosage is 30mg at the maximum. Fe 3 O 4 Exhibits an adsorption capacity (or adsorption removal rate) of (2) and modifies Fe 3 O 4 Similar trend, only Fe 3 O 4 Has an adsorption capacity lower than that of modified Fe 3 O 4 The adsorption capacity of (c). For example, at 10mg Fe 3 O 4 In the amount of (B), fe 3 O 4 The adsorption capacity of (A) reached a peak value of 188.4mg/g. Thus, the modified Fe of the present invention 3 O 4 Higher adsorption efficiency can be achieved with less adsorbent usage.
The inventors believe that mass transfer between the soluble phase and the adsorbent is enabled because the driving force increases as the initial concentration of adsorbent increases to overcome the mass transfer resistance. Removal efficiency is improved by increasing the amount of adsorbent used, since there is more adsorbent contact surface and higher availability of active adsorbent sites than adsorbent molecules. After an optimal dosage of adsorbent, an increase in the dosage of adsorbent has no major impact on the removal efficiency due to the gradient distribution between the adsorbent and the adsorbent concentration and saturation of the active adsorption sites. After the adsorption sites are saturated, continued increase in adsorbent dosage results in overlapping adsorption sites and hence a decrease in adsorption capacity.
(3) Influence of the pH value
The pH values of the Congo red wastewater solutions were adjusted to 4, 5, 6, 7, 8 and 9, respectively, by 0.1M HCl and NaOH, and 5mg of hydrocarbon degrading bacteria modified activated carbon was added to a 50mL bottle and mixed with the wastewater solutions. The vial was placed on a shaker at 100rpm at room temperature (25 ℃) until equilibrium adsorption was reached. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer. Furthermore, a control experiment was performed using activated carbon instead of modified activated carbon. The results are shown in FIG. 8 a.
As shown in FIG. 8a, the Congo red adsorption capacity of the modified activated carbon has little change with the increase of pH from 4 to 7, and is stabilized at 222.9mg/g-225.5mg/g. At pH values above 7, the modified activated carbon showed a slight downward trend. At pH =9, the adsorption capacity of the modified activated carbon was only 162.6mg/g. With the increase of the pH value, the adsorption capacity of the activated carbon to the Congo red tends to decrease. At pH =9, the adsorption capacity of the activated carbon was only 15.5mg/g. Therefore, the pH value of the wastewater solution is in the range of 4-7, and the adsorption efficiency of the modified activated carbon is better.
Adjusting the pH value of the Congo red wastewater solution to 5, 7, 9 and 11 respectively by 0.1M HCl and NaOH, and adding 5mg of hydrocarbon degrading bacteria modified magnetic cluster nano Fe into a 50mL bottle 3 O 4 Mixing with the wastewater solution. The vial was placed on a shaker at 100rpm at room temperature (25 ℃) until adsorption equilibrium was reached. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer. And, using Fe 3 O 4 Substituted for modified Fe 3 O 4 Control experiments were performed. The results are shown in FIG. 8 b.
As shown in FIG. 8b, the modified Fe increases with pH from 5 to 11 3 O 4 The adsorption capacity of congo red tends to increase first and then decrease. Modified Fe at pH =7 3 O 4 The adsorption capacity of (A) reached a peak of 320.1mg/g. Modified Fe at pH above 7 3 O 4 The adsorption capacity of (a) decreases rapidly. Fe 3 O 4 Fe with capacity of adsorbing Congo red and modified 3 O 4 Similar trends. At pH =7, fe 3 O 4 The adsorption capacity of (A) reached a peak of 135.8mg/g. Therefore, the pH value of the wastewater solution is in the range of 5-7, and Fe is modified 3 O 4 The adsorption efficiency of (2) is good.
Based on the above analysis, pH is one of the key parameters in the adsorption process. The adsorption capacity is highly dependent on the pH of the solution, since a change in the pH of the solution results in a change in the degree of ionization of the adsorbed molecules and the surface properties of the adsorbent. The adsorption capacity on the adsorbent surface is mainly influenced byThe loading of the adsorbent surface, and the adsorbent surface itself, is also affected by the pH of the solution. Congo Red is an anionic dye, the adsorbent has a positive charge at lower pH values, and therefore, due to the electrostatic attraction between the adsorbent and Congo Red and H + High interaction with Congo red improves the adsorption capacity. The decrease in alkaline pH removal efficiency may be due to electrostatic repulsion between the negatively charged surface of the bio-based nanomaterial and the anions, thereby causing the anions to adsorb onto the active sites on the surface of the adsorbent.
Study of kinetics
Kinetic experiments were obtained as follows: 500mg/L of bio-based nano material and 1L of Congo red wastewater of 80mg/L are mixed, and magnetic stirring is carried out at the stirring speed of 100rpm. The sampling was performed for 1, 5, 10, 15, 20, 25, 30, 45, 60, 75, 90, 120, 180, and 240 minutes, and 5mL of the sample was taken out each time. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer. The adsorption kinetics of the bio-based nano material to Congo red are described by adopting a pseudo first-order kinetic equation (formula (1)) and a pseudo second-order kinetic equation (formula (2)).
ln(q e -q t )＝ln q e -k 1 t (1)
Wherein q is e (mg/g) is the amount of Congo Red adsorbed at equilibrium, in mg/g, and k 1 (min -1 ) And k 2 (g/(mg. Min)) are the pseudo first order reaction rate constant and the pseudo second order reaction rate constant, respectively.
The results are shown in tables 1 and 2.
TABLE 1 kinetic parameters of activated carbon and Hydrocarbon-degrading bacteria modified Nano-activated carbon
TABLE 2 magnetic cluster Fe 3 O 4 Hydrocarbon degrading bacteria modified nanometer magnetic cluster Fe 3 O 4 Dynamic parameter of (2)
The results obtained from tables 1 and 2 were compared by comparing the correlation coefficient (R) of the kinetic equation 2 ) It can be seen that the pseudo-first order kinetic model in all states fits better with the experimental data. The pseudo first order kinetics allow for a more accurate assessment of the adsorption of congo red dye on the adsorbents used in the present invention. Furthermore, it can be concluded that the available adsorption sites play a key role in the adsorption rate.
Isothermal adsorption study
The adsorption isotherm experiments were carried out as follows: 40mL 80mg/L Congo red wastewater is added into a 50mL bottle, and then 5mg of bio-based nano material is added. The pH of the wastewater was adjusted to 7.0. The vial was placed on a shaker at 100rpm at room temperature (25 ℃) until adsorption equilibrium was reached. The resulting mixture was centrifuged at 6000g for 10 minutes, and the absorbance values before and after adsorption of the wastewater were measured at 497nm by means of an ultraviolet-visible (UV-Vis) spectrophotometer. Fitting was performed by Langmuir (Langmuir), frendlich (Freundlich) and tmkin (Temkin) adsorption isotherm models. The results are shown in tables 3 and 4.
TABLE 3 isothermal adsorption model parameters for adsorption of Congo red by hydrocarbon degrading bacteria modified nano activated carbon
TABLE 4 Hydrocarbon-degrading bacteria modified nanometer magnetic cluster Fe 3 O 4 Isothermal adsorption model parameters for adsorbing Congo red
Wherein q is m (mg/g) and K L (L/mg) is the maximum adsorption capacity and equilibrium adsorption constant, Q, respectively, of the Langmuir adsorption isothermal model m,exp (mg/g) is the maximum adsorption capacity, Q, obtained by experiment m,cal (mg/g) is the maximum adsorption capacity, K, calculated by the adsorption isotherm model formula F (mg/g)(L/mg) 1/n In relation to the magnitude of the driving force for adsorption, 1/n represents the degree of nonlinearity between the solution concentration and adsorption, b T (J/mol) is a constant relating to the heat of adsorption, K T (L/mg) is the equilibrium binding constant corresponding to the maximum binding energy.
According to the results obtained in tables 3 and 4, and by comparing the correlation coefficients (R) 2 ) It can be seen that the experimental data obtained more closely fit the langmuir isothermal model. Therefore, it can be determined that the adsorption of congo red by the bio-based nanomaterial is performed in a monolayer form.
Although a few embodiments of the present general inventive concept have been shown and described, it will be appreciated by those skilled in the art that changes may be made in these embodiments without departing from the principles and spirit of the general inventive concept, the scope of which is defined in the appended claims and their equivalents.
Claims (6)
1. A method for preparing a bio-based nanomaterial, comprising:
obtaining a suspension of hydrocarbon degrading bacteria for modification comprising the steps of:
providing a single hydrocarbon degrading bacterial strain, culturing the single hydrocarbon degrading bacterial strain in an enrichment medium to obtain thallus in a logarithmic growth phase, centrifuging and washing by using sterile water, and suspending the thallus in the sterile water to obtain a hydrocarbon degrading bacterial suspension for modification, wherein the density of the hydrocarbon degrading bacterial suspension is determined by measuring the absorbance value at 600nm, and the OD of the hydrocarbon degrading bacterial suspension for modification 600 The value is 0.5 to 2.0;
adding a nano material into a hydrocarbon degrading bacteria suspension for modification under the condition of stirring, wherein the mass ratio of the nano material to the hydrocarbon degrading bacteria suspension is 1 to 1,
wherein the nano material is magnetic cluster ferroferric oxide (Fe) 3 O 4 ) The cluster ferroferric oxide is prepared by a one-step solvothermal method:
adding FeCl 0.5-2.0g into ethylene glycol 60-100mL 3 And 2.7-4.5g polyacrylic acid, stirring to completely dissolve the polyacrylic acid, adding 15-35mL of hydroxylamine, stirring to completely dissolve the hydroxylamine, transferring the hydroxylamine into an autoclave, treating the hydroxylamine in a water bath at 160-250 ℃ for 1-5 hours, centrifuging, retaining the precipitate, washing the precipitate by using absolute ethyl alcohol, drying the precipitate at 40-80 ℃ for 12-36 hours to obtain the cluster ferroferric oxide,
wherein providing a single hydrocarbon degrading bacterial strain comprises the steps of:
obtaining a surface seawater or surface sediment sample from an offshore area polluted by petroleum hydrocarbon;
adding a surface seawater or surface sediment sample into a domestication culture medium for domestication, wherein the domestication culture medium is autoclaved natural seawater containing 0.1-2% of crude oil by mass fraction;
after acclimation for a predetermined time, a single hydrocarbon degrading bacterial strain is obtained by solid plate trisection.
2. The method for preparing bio-based nano-material according to claim 1, wherein,
the preset time in the domestication process is 2-5 periods, and the time of each period is 7 days;
the enrichment culture medium comprises 1-10g/L of inorganic salt, 5-20g/L of protein and 1-6g/L of muscle tissue extract.
3. The method for preparing bio-based nanomaterial according to claim 2, wherein the inorganic salt comprises any one of sodium chloride, potassium chloride, sodium nitrate, potassium nitrate, sodium sulfate, and potassium sulfate, or any combination thereof;
the protein comprises any one of peptone, fish protein peptide, egg white protein and whey protein or any combination thereof;
the muscle tissue extract comprises any one of beef extract, pork extract, chicken extract and beef extract or any combination thereof.
4. A method for treating organic dyes in wastewater by using bio-based nano materials, comprising the following steps:
providing a bio-based nanomaterial obtained according to the production method of any one of claims 1 to 3;
standing the wastewater for a preset time, and then pretreating the wastewater by using a filter;
adding the bio-based nano material into the pretreated wastewater, and adsorbing the organic dye under the conditions that the temperature is 15-45 ℃ and the rotating speed of a shaking table is 80-150 rpm.
5. The process according to claim 4, wherein the adsorption of the organic dye is carried out in a shaker at a pH of from 4 to 11.
6. The method of claim 4 or 5, wherein the organic dye comprises any one of Congo Red, malachite Green, methyl Violet, crystal Violet, or any combination thereof.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110509146.9A CN113249370B (en) | 2021-05-11 | 2021-05-11 | Preparation method of bio-based nano material and method for treating organic dye in wastewater |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202110509146.9A CN113249370B (en) | 2021-05-11 | 2021-05-11 | Preparation method of bio-based nano material and method for treating organic dye in wastewater |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN113249370A CN113249370A (en) | 2021-08-13 |
| CN113249370B true CN113249370B (en) | 2022-12-13 |
Family
ID=77222565
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN202110509146.9A Active CN113249370B (en) | 2021-05-11 | 2021-05-11 | Preparation method of bio-based nano material and method for treating organic dye in wastewater |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN113249370B (en) |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102199589A (en) * | 2010-12-27 | 2011-09-28 | 北京师范大学 | Immobilized microspheres for remediation of petroleum contaminated soil, preparation method thereof and application thereof |
| CN102423697A (en) * | 2011-10-19 | 2012-04-25 | 湖南大学 | Immobilized biological adsorbent, its preparation method and application |
| CN105695445A (en) * | 2016-03-28 | 2016-06-22 | 舟山光大检测研究院有限公司 | Immobilized microbial agent for treating oil-containing sewage as well as preparation method and application of immobilized microbial agent |
| CN106282153A (en) * | 2016-08-31 | 2017-01-04 | 武汉大学 | Sandwich micro nanometer fiber composite membrane of loading microorganisms and its preparation method and application |
| CN108637005A (en) * | 2018-05-14 | 2018-10-12 | 江苏金环环保设备有限公司 | It is a kind of to repair polycyclic aromatic hydrocarbons contaminated composite material, preparation method and the usage |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CA3031942A1 (en) * | 2019-01-30 | 2020-07-30 | Satinder Kaur Brar | In situ enzymatic degradation of hydrocarbon-polluted soils |
-
2021
- 2021-05-11 CN CN202110509146.9A patent/CN113249370B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102199589A (en) * | 2010-12-27 | 2011-09-28 | 北京师范大学 | Immobilized microspheres for remediation of petroleum contaminated soil, preparation method thereof and application thereof |
| CN102423697A (en) * | 2011-10-19 | 2012-04-25 | 湖南大学 | Immobilized biological adsorbent, its preparation method and application |
| CN105695445A (en) * | 2016-03-28 | 2016-06-22 | 舟山光大检测研究院有限公司 | Immobilized microbial agent for treating oil-containing sewage as well as preparation method and application of immobilized microbial agent |
| CN106282153A (en) * | 2016-08-31 | 2017-01-04 | 武汉大学 | Sandwich micro nanometer fiber composite membrane of loading microorganisms and its preparation method and application |
| CN108637005A (en) * | 2018-05-14 | 2018-10-12 | 江苏金环环保设备有限公司 | It is a kind of to repair polycyclic aromatic hydrocarbons contaminated composite material, preparation method and the usage |
Non-Patent Citations (2)
| Title |
|---|
| A Wang等.Enhanced removal of Congo red dye from aqueous solution by surface modified activated carbon with bacteria.《J Appl Microbiol.》.2021,第131卷(第5期),第2270-2279页. * |
| Enhanced removal of Congo red dye from aqueous solution by surface modified activated carbon with bacteria;A Wang等;《J Appl Microbiol.》;20210421;第131卷(第5期);第2页右栏第2-3段，第3页左栏第2段、第4-7段、右栏第1段 * |
Also Published As
| Publication number | Publication date |
|---|---|
| CN113249370A (en) | 2021-08-13 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| Daneshvar et al. | A comparative study of methylene blue biosorption using different modified brown, red and green macroalgae–Effect of pretreatment | |
| Mella et al. | Preparation and characterization of activated carbon produced from tannery solid waste applied for tannery wastewater treatment | |
| Aksu et al. | Methylene Blue biosorption by Rhizopus arrhizus: Effect of SDS (sodium dodecylsulfate) surfactant on biosorption properties | |
| Liu et al. | Adsorption of an anionic azo dye by cross-linked chitosan/bentonite composite | |
| Ergene et al. | Removal of Remazol Brilliant Blue R dye from aqueous solutions by adsorption onto immobilized Scenedesmus quadricauda: Equilibrium and kinetic modeling studies | |
| Biswas et al. | Chitosan–clay composites for wastewater treatment: a state-of-the-art review | |
| Selatnia et al. | Biosorption of Ni2+ from aqueous solution by a NaOH-treated bacterial dead Streptomyces rimosus biomass | |
| Binupriya et al. | Sequestration of Reactive Blue 4 by free and immobilized Bacillus subtilis cells and its extracellular polysaccharides | |
| Esmaeli et al. | Acidic dye wastewater treatment onto a marine macroalga, Nizamuddina zanardini (Phylum: Ochrophyta) | |
| Song et al. | Biocompatible G-Fe3O4/CA nanocomposites for the removal of Methylene Blue | |
| Douissa et al. | Macroscopic and microscopic studies of methylene blue sorption onto extracted celluloses from Posidonia oceanica | |
| Sargın et al. | Microfungal spores (Ustilago maydis and U. digitariae) immobilised chitosan microcapsules for heavy metal removal | |
| Reck et al. | Protein fractionation of Moringa oleifera Lam. seeds and functionalization with magnetic particles for the treatment of reactive black 5 solution | |
| Si et al. | Exploring strategies for adsorption of azo dye Congo Red using free and immobilized biomasses of Trametes pubescens | |
| Li et al. | Characterization of cadmium removal by Rhodotorula sp. Y11 | |
| Gao et al. | ZIF-8@ s-EPS as a novel hydrophilic multifunctional biomaterial for efficient scale inhibition, antibacterial and antifouling in water treatment | |
| Nie et al. | Bio-flocculation of Microcystis aeruginosa by using fungal pellets of Aspergillus oryzae: Performance and mechanism | |
| Kim et al. | Application of a polyethylenimine-modified polyacrylonitrile-biomass waste composite fiber sorbent for the removal of a harmful cyanobacterial species from an aqueous solution | |
| CN113249370B (en) | Preparation method of bio-based nano material and method for treating organic dye in wastewater | |
| Mitra et al. | Carboxymethyl Chitosan modified Montmorillonite for Efficient Removal of Cationic Dye from Waste Water. | |
| Gün Gök et al. | Effective removing of remazol black B by the Polyacrylamide Cryogels modified with Polyethyleneimine | |
| JPWO2004058423A1 (en) | Method for removing heavy metals from incineration ash | |
| Arivizhivendhan et al. | Functioned silver nanoparticle loaded activated carbon for the recovery of bioactive molecule from bacterial fermenter for its bactericidal activity | |
| Zazouli et al. | Application of azollafiliculoides biomass in acid black 1 dye adsorption from aqueous solution | |
| Kawasaki et al. | Identification and characterization of the S-layer formed on the sheath of Thiothrix nivea |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |