阅读说明：本技术 一种纳米乳液及其制备方法和应用 (Nano emulsion and preparation method and application thereof ) 是由 赵莎莎 陈士勇 张欢乐 王耀国 于 2021-07-09 设计创作，主要内容包括：一种纳米乳液及其制备方法和应用,所述纳米乳液包括氨基酸表面活性剂和有机溶剂；所述氨基酸表面活性剂包覆所述有机溶剂。本发明利用纳米乳液,靶向吸附在油泥颗粒表面,缓慢释放出包埋的溶剂,与表活剂共同作用剥离原油,具有显著的清洗含油污泥的效果,并且该方法成本低,可降解,无二次污染。(A nano-emulsion, a preparation method and an application thereof, wherein the nano-emulsion comprises an amino acid surfactant and an organic solvent; the amino acid surfactant coats the organic solvent. The nano emulsion is adsorbed on the surface of oil sludge particles in a targeted mode, the embedded solvent is slowly released, the nano emulsion and the surfactant act together to strip crude oil, the effect of cleaning oily sludge is remarkable, and the method is low in cost, degradable and free of secondary pollution.)

1. A nanoemulsion characterized in that it comprises an amino acid surfactant and an organic solvent;

the amino acid surfactant coats the organic solvent.

2. The nanoemulsion of claim 1, wherein the organic solvent is selected from at least one of ethyl acetate, acetone, petroleum ether;

preferably, the amino acid surfactant is protein powder or C₁₅～C₂₀The acyl chloride compound and the sulfonate compound are reacted to prepare the compound;

preferably, in the nano emulsion, the mass ratio of the amino acid surfactant to the organic solvent is 2-4: 1.

3. The nanoemulsion of claim 1, further comprising an amine compound and water in the nanoemulsion;

preferably, the amine compound is selected from at least one of diethanolamine and triethanolamine;

preferably, in the nano emulsion, the mass content of the amine compound is 0.4-1.5%;

the mass content of the water is 90-98%;

preferably, the molecular weight of the amino acid surfactant is 5000-6000;

preferably, the surface tension of the nano emulsion is 25.47-25.66 mN/m.

4. A method of preparing a nanoemulsion as claimed in any one of claims 1 to 3, characterised in that it comprises:

reacting and ultrasonically treating a material I containing an amino acid surfactant and an organic solvent to obtain the nano emulsion;

the pH value of the material I is 6-6.5.

5. The method according to claim 4, wherein the amino acid surfactant is prepared by:

mixing water, protein powder, C₁₅～C₂₀Reacting the acyl chloride compound, the sulfonate compound and a material II of an organic solvent, and performing ultrasonic treatment to obtain the amino acid surfactant;

preferably, the preparation method comprises:

mixing water, protein powder, C₁₅～C₂₀Mixing the acyl chloride compound, the sulfonate compound and the material III of the organic solvent, reacting, and performing ultrasonic treatment to obtain the nano emulsion;

the pH value of the material III is 6-6.5;

preferably, said C₁₅～C₂₀The acyl chloride compound of (a) is selected from at least one of cocoyl chloride and palmitoyl chloride; the sulfonate compound is at least one of sodium isethionate and sodium 3-chloro-2-hydroxypropanesulfonate;

preferably, the water, protein powder and C₁₅～C₂₀The mass ratio of the acyl chloride compound to the sulfonate compound is 100-300: 1-10: 0.5-1: 0.5;

preferably, the organic solvent and C₁₅～C₂₀The volume ratio of the acyl chloride-based compound is 1-10: 1;

preferably, the reaction conditions are: the reaction temperature is 55-60 ℃, and the reaction time is 2-5 h;

preferably, the conditions of the ultrasound are: the ultrasonic frequency is 10-20 KHz, and the ultrasonic time is 1-5 min.

6. A cleaning solution, characterized in that the cleaning solution comprises a nanoemulsion;

the nano emulsion is at least one selected from the nano emulsion described in any one of claims 1 to 3 and the nano emulsion obtained by the preparation method described in any one of claims 4 to 5.

7. A method for preparing the cleaning liquid as claimed in claim 6, characterized in that the method comprises: diluting the nano emulsion, and adjusting the pH to 9-10 to obtain the cleaning solution.

8. The preparation method of claim 7, wherein the mass concentration of the nano emulsion in the cleaning solution is 1-5%;

preferably, the solvent for dilution is selected from water.

9. A method for cleaning oily sludge is characterized in that cleaning solution is mixed with the oily sludge and cleaned, and then the oily sludge can be cleaned;

the cleaning liquid is at least one selected from the cleaning liquids described in claim 6 and the cleaning liquids obtained by the production method described in claim 7 or 8.

10. The method of claim 9, further comprising heating the mixture with agitation; the heating and stirring conditions are as follows: the heating temperature is 60-70 ℃, and the stirring time is 60 min;

preferably, the mass volume ratio of the oily sludge to the cleaning fluid is 1-2: 3-6;

preferably, the oily sludge is cleaned by physical action, and the centrifuged liquid can be reused.

Technical Field

The invention belongs to the technical field of oily sludge treatment, and particularly relates to a nano emulsion and a preparation method and application thereof.

Background

At present, about 1000 million tons of oily sludge is urgently needed to be treated every year in China, the sources of the oily sludge mainly comprise the oily sludge generated in the processes of crude oil exploitation, gathering and transportation, refining and oil field sewage treatment, and the generation amount of the oily sludge is increased year by year due to exploitation of shale gas and offshore oil fields. The oily sludge belongs to hazardous waste, and volatile hydrocarbon pollutes air if the oily sludge is not treated in time; secondly, the long-term stacking of the soil and the water causes the pollution of soil and water in a wider range; and the contained teratogenic, carcinogenic and mutagenic substances directly harm the health of people and livestock.

The prior oily sludge treatment technology mainly comprises the following steps: hot washing technology, thermal desorption technology, solidification technology, freezing and melting technology, wet oxidation technology, ultrasonic treatment technology, extraction and biological method, biological degradation method and the like. The hot washing method is a widely used method at present, has less investment and lower operation cost compared with other methods, and is one of effective methods for reduction and resource utilization. However, the oil content of the residue treated by the method is often higher than the standard and the used chemical agent causes secondary pollution to the environment. The thermal desorption method has high crude oil recovery rate, but is difficult to popularize and apply on a large scale due to high requirements on reaction conditions and large amount of generated waste gas. The curing process does not solve the problem fundamentally, only eliminates the hazard temporarily, and wastes limited petroleum resources. The freeze-fusion method has low energy consumption but low oil recovery rate. The oxidation method has the hidden trouble of secondary pollution. Extraction + biological processes are limited by their extractant. The biodegradation method is not suitable for the oily sludge with high oil content, and the treatment period is longer.

The organic solvent has good viscosity reduction and dispersion effects on the oily sludge, the surfactant can form micelles with hydrophobic cores in the solution when the concentration of the surfactant is higher than the critical micelle concentration of the surfactant, and the micelles can provide a hydrophobic 'hypothetical phase' for distribution of petroleum hydrocarbon, so that the solubility of the petroleum hydrocarbon in the aqueous phase is remarkably improved, and the migration of pollutants from the surface of solid particles to the aqueous phase is promoted.

Disclosure of Invention

The invention provides a nano emulsion, a preparation method and application thereof, which utilize protein powder and C₁₅～C₂₀The acyl chloride-based compound, the sulfonate compound and the organic solvent are synthesized into the nano emulsion, the nano emulsion has nano-sized microcapsules, and the surfactant micelle is coated around the organic solvent to mediateThe cleaning agent is adsorbed on the surface of oil sludge particles in a targeted manner, slowly releases an embedded solvent, and peels off crude oil under the combined action of the surface active agent, so that the cleaning agent has a remarkable effect of cleaning oil-containing sludge.

According to an aspect of the present application, there is provided a nanoemulsion comprising an amino acid surfactant and an organic solvent; the amino acid surfactant coats the organic solvent.

Optionally, the organic solvent is selected from at least one of ethyl acetate, acetone, petroleum ether.

Preferably, the organic solvent is selected from ethyl acetate.

Optionally, the amino acid surfactant is protein powder, C₁₅～C₂₀The acyl chloride compound and the sulfonate compound are reacted to prepare the compound.

Optionally, in the nano emulsion, the mass ratio of the amino acid surfactant to the organic solvent is 2-4: 1.

Optionally, an amine compound and water are also included in the nanoemulsion.

Optionally, the amine compound is selected from at least one of diethanolamine and triethanolamine.

Optionally, in the nano emulsion, the mass content of the amine compound is 0.4-1.5%; the mass content of the water is 90-98%.

Optionally, the amino acid surfactant has a molecular weight of 5000-6000.

Optionally, the surface tension of the nanoemulsion is 25.47-25.66 mN/m.

According to a further aspect of the present application, there is provided a method of preparing a nanoemulsion as described above, comprising: reacting and ultrasonically treating a material I containing an amino acid surfactant and an organic solvent to obtain the nano emulsion; the pH value of the material I is 6-6.5.

Optionally, the amino acid surfactant is prepared by the following method:

mixing water, protein powder, C₁₅～C₂₀Acyl chloride group ofReacting the compound with a material II of an organic solvent, and carrying out ultrasonic treatment to obtain the amino acid surfactant.

Optionally, the preparation method comprises:

mixing water, protein powder, C₁₅～C₂₀Mixing the acyl chloride compound, the sulfonate compound and the material III of the organic solvent, reacting, and performing ultrasonic treatment to obtain the nano emulsion; the pH value of the material III is 6-6.5.

Optionally, the C₁₅～C₂₀The acyl chloride compound of (b) is at least one selected from cocoyl chloride and palmitoyl chloride.

Preferably, said C₁₅～C₂₀The acid chloride based compound of (a) is selected from cocoyl chloride.

Preferably, the sulfonate compound is at least one selected from sodium isethionate and sodium 3-chloro-2-hydroxypropanesulfonate.

Optionally, the water, protein powder and C₁₅～C₂₀The mass ratio of the acyl chloride compound to the sulfonate compound is 100-300: 1-10: 0.5-1: 0.5.

optionally, the organic solvent and C₁₅～C₂₀The volume ratio of the acyl chloride-based compound (b) is 1-10: 1.

Optionally, the reaction conditions are: the reaction temperature is 55-60 ℃, and the reaction time is 2-5 h.

Optionally, the reaction conditions are: the reaction temperature is 55-60 ℃, and the reaction time is 2-5 h.

Optionally, the conditions of the ultrasound are: the ultrasonic frequency is 10-20 KHz, and the ultrasonic time is 1-5 min.

Optionally, the conditions of the ultrasound are: the ultrasonic frequency is 10-20 KHz, and the ultrasonic time is 3-4 min.

According to yet another aspect of the present application, there is provided a cleaning solution comprising a nanoemulsion; the nanoemulsion is selected from at least one of the nanoemulsion as defined in any one of the above claims and the nanoemulsion obtained according to the preparation method as defined in any one of the above claims.

According to still another aspect of the present application, there is provided a method of preparing the cleaning liquid as described above, the method comprising: diluting the nano emulsion, and adjusting the pH to 9-10 to obtain the cleaning solution.

Optionally, the solvent for dilution is selected from water.

Optionally, the mass concentration of the nano emulsion in the cleaning solution is 1-5%.

According to still another aspect of the present application, there is provided a method for cleaning oily sludge, comprising mixing a cleaning solution with the oily sludge, heating and stirring to clean the oily sludge; the cleaning liquid is at least one selected from the cleaning liquids described above and the cleaning liquids obtained by the production methods described above.

Optionally, the conditions of heating and stirring are as follows: the heating temperature is 60-70 ℃, and the stirring time is 60 min.

Optionally, the mass-to-volume ratio of the oily sludge to the cleaning fluid is 1-2: 3 to 6.

Optionally, the mass-to-volume ratio of the oily sludge to the cleaning fluid is 1: 3.

optionally, the cleaning liquid after cleaning the oily sludge can be reused.

Optionally, the cleaning solution after the oil-containing sludge is cleaned can be reused for 1-10 times.

Preferably, the cleaning liquid after cleaning the oily sludge can be reused for 4 times.

Optionally, the cleaning solution after cleaning the oily sludge can be obtained by precipitating and centrifugally separating the mixture for cleaning the oily sludge.

Optionally, the method of cleaning oily sludge comprises: performing ultrasonic treatment at the ultrasonic frequency of 10-20 KHz for 1-5 min, diluting the emulsion with clear water, adjusting the pH value with NaOH to form a cleaning solution, adding oily sludge into the cleaning solution, stirring and cleaning for 60min under the heating condition of 60-70 ℃, precipitating the mixture, and performing centrifugal separation.

The degradable nano emulsion can be used for efficiently and environmentally protecting oil stains on the surfaces of oily sludge particles, and has a remarkable effect.

Optionally, the method of cleaning oily sludge comprises:

1) and (3) nano emulsion synthesis: adding 3-10 g of protein powder, 1.5-3 g of ethyl acetate, 0.5-3 g of cocoyl chloride, 1.5-2 g of diethanolamine and 0.5-1 g of sodium isethionate into 300mL of clear water, adjusting the pH to 6-6.5 by using HCl, and stirring for 2 hours at the temperature of 55-60 ℃;

2) ultrasonic preparation: performing ultrasonic treatment at the ultrasonic frequency of 10-20 KHz for 1-5 min;

3) preparing a cleaning solution: diluting the emulsion to a mass concentration of 1-5% with clear water, and adjusting the pH to 9-10 with NaOH to form a cleaning solution;

4) adding the oily sludge into the cleaning solution, and stirring and cleaning for 30-60 min under the heating condition of 60-70 ℃;

5) precipitating the mixture cleaned in the step 4), performing centrifugal separation at the speed of 3000r/min, recycling the separated liquid as cleaning liquid, recycling the cleaning liquid, and cleaning new oily sludge for the 9 th time in a circulating way, wherein the oil content of the cleaned sludge is 0.78%. The cleaning solution is used for 10 times in total, and the oil removal rate can reach more than 97 percent when new oily sludge is cleaned each time.

Wherein, the pH value of the solution is adjusted to 7-9 by diethanolamine and is adjusted to 6-6.5 by hydrochloric acid.

Alternatively, the ethyl acetate: the volume ratio of the cocoyl chloride is 1-3: 1, and the oily sludge is from an oil field production site.

Optionally, in the step 4), the mass-to-volume ratio of the oily sludge to the cleaning solution is 1: 3.

In this application, C₁₅～C₂₀And the like refer to the number of carbon atoms that the group contains.

The invention has the beneficial effects that:

(1) using protein powder and C₁₅～C₂₀The amino acid surfactant is formed by the reaction of acyl chloride compound and sulfonate compound, lipophilic group of the amino acid surfactant is embedded with organic solvent to form nano capsules, and the nano emulsion is finally obtained through ultrasonic preparation, wherein hydrophilic groups on the surface of the nano emulsion mediate the nano emulsion to be adsorbed on the surface of oil sludge particles in a targeted manner, and the nano emulsion is slowly adsorbed on the surface of the oil sludge particlesReleasing the coated solvent, and acting with surfactant to strip the crude oil.

(2) 1-5% of cleaning solution prepared from the nano emulsion can be used for cleaning oily sludge, the pH of the cleaning solution is adjusted to 9-10 because carboxyl in the nano emulsion can be dissociated when the cleaning solution is alkaline, the nano emulsion has extremely strong hydrophilicity, and a hydrophilic membrane is formed on the surface of oil by enrichment, so that the adhesion between lipid substances and oil sludge particles is reduced, and the solubilization and desorption effects of the surfactant are enhanced.

(3) A green and efficient method for cleaning oily sludge is developed by taking the oil content after cleaning as an index, and has the following three advantages: firstly, nanoparticles are adsorbed and dispersed on the surface of oil sludge particles in a targeted manner; secondly, slowly releasing the solvent; thirdly, the amino acid surfactant formed by the reaction accelerates the dissolution of the pollutants.

(4) The production process of the nano emulsion has low requirement, the raw materials for production are convenient to obtain, the synthesis and preparation are simple and easy to operate, the cost for cleaning the oily sludge is low, and the cleaning solution can be recycled for repeated use, so that the nano emulsion has wide application prospect.

Drawings

FIG. 1 is a schematic view of the "microcapsule" of the nano-emulsion prepared in example 1 of the present application under a microscope.

Fig. 2 is a schematic diagram illustrating the effect of the nano-emulsion prepared at different ultrasonic times on the cleaning effect of the oily sludge in example 10 of the present application.

Fig. 3 is a schematic diagram illustrating the influence of the nano-emulsion prepared in example 8 on the cleaning effect of the oily sludge in different cleaning solution circulation times.

Detailed Description

Unless otherwise specified, the raw materials and catalysts in the examples of the present application were all purchased commercially.

The oily sludge comes from the production field of the Changqing oil field.

Protein powder, food grade, performance standard: GB2760-2014, available from Zhejiang intermediate-range pharmaceutical industry Co.

Example 1

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1g of ethyl acetate, 0.5g of cocoyl chloride and 1.5g of diethanolamine into 100mL of clear water, adjusting the pH value to 7.5, stirring for 3 hours at the temperature of 55 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 2 hours at the temperature of 60 ℃;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 3 min;

(3) preparing a cleaning solution: diluting the emulsion to 3% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 60 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 1.93:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3.

The molecular weight of the amino acid surfactant was 5000.

The surface tension of the nano emulsion is 25.47mN/m, and the test method is a suspension loop method. A schematic diagram of a microcapsule of the prepared nano emulsion is shown in fig. 1, fig. 1 is a schematic diagram of a "microcapsule" of the nano emulsion prepared in example 1 of the present application, which is enlarged 1000 times under a microscope, in fig. 1, a microsphere with a particle size of 35977.80nm is an organic solvent, a microsphere with a particle size of 4623.66nm is a surfactant micelle, the surfactant has a hydrophilic lipophilic group, the lipophilic group is coated around the organic solvent microsphere, the hydrophilic group mediates the targeted adsorption of the hydrophilic group on the surface of oil sludge, and the crude oil is better stripped under the action of the hydrophilic group and the oil sludge.

The initial oil content of the tested oil-containing sludge is 30%, the surfactant in the nano emulsion mediates the dissolution of amino acid molecules to accelerate the dissolution of pollutants through the action of a solvent, and the oil removal rate reaches 98.96%.

Example 2

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 1g of cocoyl chloride and 2g of diethanolamine into 200mL of clear water, adjusting the pH value to 8, stirring for 2 hours at the temperature of 60 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 3 hours at the temperature of 55 ℃;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 1 min;

(3) preparing a cleaning solution: diluting the emulsion to 4% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 60 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 1.45:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3. The molecular weight of the amino acid surfactant is 6000. The surface tension of the nano emulsion is 25.63mN/m, and the test method is a suspension loop method.

The initial oil content of the tested oil-containing sludge is 30 percent, and the oil removal rate of the cleaning solution for cleaning the oil-containing sludge is 95.03 percent.

Example 3

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 0.5g of cocoyl chloride and 1.5g of diethanolamine into 100mL of clear water, adjusting the pH value to 7.5, stirring for 3 hours at the temperature of 55 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 2 hours at the temperature of 60 ℃;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 3 min;

(3) preparing a cleaning solution: diluting the emulsion to 3% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding the oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 65 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 2.89:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3.

The molecular weight of the amino acid surfactant was 5000.

The surface tension of the nano emulsion is 25.47mN/m, and the test method is a suspension loop method.

The initial oil content of the tested oil-containing sludge is 30 percent, and the oil removal rate of the first cleaning of the cleaning solution is 98.96 percent; the cleaning solution is reused for one time to clean new oily sludge, and the oil removal rate is 98.76%.

Example 4

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 1g of cocoyl chloride and 2g of diethanolamine into 200mL of clear water, adjusting the pH value to 8, stirring for 2 hours at the temperature of 60 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 3 hours at the temperature of 55 ℃;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 2 min;

(3) preparing a cleaning solution: diluting the emulsion to 4% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 60 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 1.45:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3. The molecular weight of the amino acid surfactant is 6000. The surface tension of the nano emulsion is 25.58mN/m, and the test method is a suspension loop method.

The initial oil content of the tested oil-containing sludge is 30 percent, and the oil removal rate of the cleaning solution is 96.33 percent.

Example 5

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 0.5g of cocoyl chloride and 1.5g of diethanolamine into 300mL of clear water, adjusting the pH value to 7.5, stirring for 3 hours at the temperature of 55 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 2 hours at the temperature of 60 ℃;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 3 min;

(3) preparing a cleaning solution: diluting the emulsion to 3% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 70 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 2.89:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3.

The molecular weight of the amino acid surfactant was 5000.

The surface tension of the nano emulsion is 25.62mN/m, and the test method is a suspension loop method.

The initial oil content of the tested oil-containing sludge is 30 percent, and the oil removal rate of the cleaning solution is 98.67 percent.

Example 6

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 0.5g of cocoyl chloride and 1.5g of diethanolamine into 300mL of clear water, adjusting the pH value to 7.5, stirring at the temperature of 60 ℃ for 2 hours, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring at the temperature of 60 ℃ for 2 hours;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 2 min;

(3) preparing a cleaning solution: diluting the emulsion to 5% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 60 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 2.89:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3. The molecular weight of the amino acid surfactant was 5000. The surface tension of the nano emulsion is 25.66mN/m, and the test method is a suspension loop method.

The initial oil content of the tested oil-containing sludge is 30 percent, and the oil removal rate of the cleaning solution is 98.6 percent.

Example 7

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 0.5g of cocoyl chloride and 1.5g of diethanolamine into 300mL of clear water, adjusting the pH value to 7.5, stirring for 3 hours at the temperature of 56 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 2.5 hours at the temperature of 60 ℃;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 3 min;

(3) preparing a cleaning solution: diluting the emulsion to 1% of mass concentration by using clear water, and adjusting the pH to 9 by using NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 60 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 2.89:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3. The molecular weight of the amino acid surfactant was 5000. The surface tension of the nano emulsion is 25.62mN/m, and the test method is a suspension loop method.

The initial oil content of the tested oil-containing sludge is 30 percent, and the oil removal rate of the cleaning solution is 98.47 percent.

Example 8

(1) And (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 0.5g of cocoyl chloride and 1.5g of diethanolamine into 100mL of clear water, adjusting the pH value to 7.5, stirring for 3 hours at the temperature of 55 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 2 hours at the temperature of 60 ℃;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 3 min;

(3) preparing a cleaning solution: diluting the emulsion to 3% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 70 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 2.89:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3.

The molecular weight of the amino acid surfactant was 5000.

The surface tension of the nano emulsion is 25.47mN/m, and the test method is a suspension loop method.

The initial oil content of the tested oil-containing sludge is 30%, the recovered cleaning solution is reused for the tenth time, and new oil sludge is cleaned each time, as shown in fig. 3, and the oil removal rates are respectively 98.93%, 98.83%, 98.8%, 98.76%, 98.67%, 98.6%, 98.47%, 97.3%, 97.83% and 97.4%.

Example 9

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 1g of cocoyl chloride and 2.5g of diethanolamine into 300mL of clear water, adjusting the pH value to 9, stirring for 2 hours at the temperature of 60 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 3 hours at the temperature of 55 ℃;

(2) ultrasonic preparation: performing ultrasonic treatment at 20KHz ultrasonic frequency for 1 min;

(3) preparing a cleaning solution: diluting the emulsion to 2% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 60 ℃;

(5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 1.45:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3. The initial oil content of the tested oily sludge is 42%, and the oil removal rate is 96.17%.

The molecular weight of the amino acid surfactant is 6000.

The surface tension of the nano emulsion is 25.65mN/m, and the test method is a suspension loop method.

Example 10

A method for cleaning oily sludge by using nano emulsion comprises the following steps:

(1) and (3) nano emulsion synthesis: adding 3g of protein powder, 1.5g of ethyl acetate, 1g of cocoyl chloride and 2.5g of diethanolamine into 300mL of clear water, adjusting the pH value to 9, stirring for 2 hours at the temperature of 60 ℃, adding 0.5g of sodium isethionate, adjusting the pH value to 6 by using HCl, and stirring for 3 hours at the temperature of 55 ℃;

(2) ultrasonic preparation: respectively performing ultrasonic treatment at 20KHz ultrasonic frequency for 1min, 2min, 3min, 4min and 5 min;

(3) preparing a cleaning solution: diluting the emulsion to 2% of mass concentration with clear water, and adjusting the pH to 9 with NaOH to form a cleaning solution;

(4) adding oily sludge into the cleaning solution, and stirring and cleaning for 60min under the heating condition of 60 ℃; (5) and (4) precipitating the mixture cleaned in the step (4), performing centrifugal separation at the speed of 3000r/min, and recycling the separated liquid as a cleaning liquid.

The ethyl acetate: the cocoyl chloride is in a volume ratio of 1.45:1, and the oily sludge is sourced from the Changqing oil field production site; the mass volume ratio of the oily sludge to the cleaning liquid is 1: 3.

The molecular weight of the amino acid surfactant is 6000.

The surface tensions of the nano-emulsions prepared by ultrasonic for 1min, 2min, 3min, 4min and 5min are respectively 25.65mN/m, 24.91, 24.88, 24.65 and 24.51, and the test method is a suspension loop method. The initial oil content of the tested oil-containing sludge was 42%, and as shown in fig. 2, the oil removal rates were 96.16%, 98.67%, 99.28%, 99.12%, and 99.09%, respectively.

Although the present application has been described with reference to a few embodiments, it should be understood that various changes, substitutions and alterations can be made herein without departing from the spirit and scope of the application as defined by the appended claims.