CN116971127A - Method for cleaning mixed oil stains on textiles using supercritical fluid - Google Patents

Abstract

The invention relates to a method for cleaning mixed oil stains on textiles using supercritical fluid. A supercritical fluid-in-water microemulsion is formed in situ in the supercritical fluid. The microemulsion is used to carry the working fluid, and a circulation pump is used to forcefully circulate and statically control the fluid. The circulating fluid carries the effective cleaning components in the working fluid and is forced to pass through the object being washed. Textiles, and released on the textiles, a degradation or emulsification reaction occurs between the cleaning fluid and the oil stain, reducing the force between the oil stain and the fiber, forming a stained microemulsion, and causing it to separate from the textile under the physical action of the supercritical fluid , to achieve preliminary cleaning of textiles containing mixed oil stains; then use pure supercritical fluid for fine cleaning to remove residual working fluid and mixed oil stains to obtain clean textiles. The invention has the characteristics of simple process, convenient operation, no need for traditional padding and drying treatments, no waste water, waste gas and other pollutant emissions, and significant energy saving, emission reduction, green ecology and other characteristics.

Description

Method for cleaning mixed oil stains on textiles using supercritical fluid

Technical field

The present invention relates to a method for cleaning contaminated textiles, and in particular, to a method for cleaning mixed oil stains on textiles using supercritical fluid.

Background technique

On the market, water washing and dry cleaning are mainly used to clean daily clothing. Washing with water requires a complex surfactant formula, takes a long time to dry, and wastes water. Dry cleaning uses chemical solvents to clean clothes, mainly tetrachlorethylene, which has high cleanliness and washing efficiency. However, dry cleaning is slow, energy-consuming and costly. It can also damage fibers, damage the ozone layer and the environment. The pollution caused is also very serious. Although the ultrasonic cleaning and plasma cleaning that have emerged today have been used to some extent, they have certain limitations in the cleaning of textiles. In recent years, we have been looking for cleaning solvents that are non-toxic, non-polluting, good in cleaning effect, economical, safe and reliable.

Supercritical CO ₂ has certain dissolving ability, low surface tension and excellent diffusion ability, allowing it to easily enter the interior of the fiber, remove dirt, and cause little damage to the fiber. The washed clothes do not need to be dried again and can be recycled and reused. , good safety, low cost, wide source, and environmentally friendly, so it has broad application prospects in industrial production.

Textile cleaning is to remove various stains on the surface of the fabric through physical or chemical methods without damaging the natural feel of the fabric. During the cleaning process, surfactants are used to emulsify the stains and reduce the interaction between the stains and the fabric. , and removed from the clothing through a certain mechanical force. Ultrasonic cleaning mainly utilizes the chemical and mechanical effects produced by ultrasonic cavitation. On the one hand, the cavitation effect of ultrasonic waves causes pollutants to peel off quickly; on the other hand, it generates local high temperature and high pressure during the collapse process to accelerate the pyrolysis of water molecules, generating highly active free radicals (:H and:OH) and active substances, which disperse and Emulsify and peel off dirt to achieve cleaning purposes. However, ultrasonic cleaning technology cannot be used for clothing cleaning, because clothing will absorb sound waves, weaken the cavitation effect, and cannot achieve the cleaning effect. Plasma cleaning uses the activation of various high-energy substances in the plasma to completely remove the dirt attached to the surface of the object. Objects that have been plasma cleaned have been completely dried, and many new active groups are often formed on the surface of the object, which can greatly improve the wetting and adhesion properties of the object surface, making it widely used.

Before the present invention was made, Chinese invention patent CN110747625 A disclosed a method of using supercritical cleaning of animal fibers. On the basis of supercritical carbon dioxide microemulsion, biological enzyme technology was used to pretreat raw cotton fabrics, and desizing pretreatment was successfully obtained. For cotton fabrics with high processing and cleanliness, although the high-efficiency and specific enzyme type can achieve good cleaning results for a single slurry and pollutants, the cleaning effect is poor for fabrics containing multiple impurities, and The types of enzymes selected increase accordingly, thereby increasing the same effects between enzymes, thereby affecting the efficiency of using a single enzyme; at the same time, although this method can improve the whiteness and cleanliness of raw animal fibers to a certain extent, it cannot. Good effect in removing grease, especially mixed greases. Therefore, there is currently no relevant published literature report on how to apply supercritical fluid technology to the cleaning of textiles and change traditional water washing and current dry cleaning into ecological, green and environmentally friendly supercritical fluid dry cleaning technology.

Contents of the invention

In view of the shortcomings of the existing technology, the present invention provides a method for cleaning mixed oil stains on textiles using supercritical fluid, which has the characteristics of energy saving, environmental protection, no pollution, strong decontamination ability, and good effect.

The history of technical solutions to achieve the object of the present invention provides a method for cleaning mixed oil stains on textiles using supercritical fluid, which includes the following steps:

(1) Prepare working fluid for supercritical fluid cleaning of mixed oil stains on textiles, including surfactants, cleaning fluids, additives, and solvents;

(2) Form a supercritical fluid-in-water microemulsion in situ in the supercritical fluid, use the microemulsion to carry the working fluid, and use a circulating pump to force the fluid under the conditions of a temperature of 10 to 130°C and a pressure of 7 to 40MPa. Circulation and static control, the cycle and static time ratio is (10~1)min:1min; the circulating fluid carries the effective cleaning components in the working fluid and is forced to pass through the washed textiles and is released on the textiles, between the cleaning fluid and the oil stains Degradation or emulsification reaction occurs, reducing the force between oil stains and fibers, and forming a stained microemulsion in situ on the outer surface or outer surface of the textile. The stained microemulsion is separated from the textile under the physical action of the supercritical fluid, achieving Preliminary cleaning of textiles containing mixed oil stains;

(3) Finely clean the textiles that have been initially cleaned in step (2) using pure supercritical fluid at a temperature of 30~120℃ and a pressure of 5~35MPa to remove the remaining working fluid on the textiles and obtain clean textile.

The present invention uses supercritical fluid to clean mixed oil stains on textiles. The working fluid and the textiles containing mixed oil stains are placed in a high-pressure reaction kettle, and the high-pressure reaction kettle is connected to a supercritical fluid circulation device; the high-pressure reaction kettle is connected to a supercritical fluid circulation device; The reaction kettle includes an auxiliary kettle and a cleaning kettle. The auxiliary kettle is used to store cleaning liquid. The top of the auxiliary kettle is connected to the cleaning kettle. There is a sarong in the cleaning kettle. Textiles containing mixed oil stains are placed in the sarong. On the sarong A number of through holes are provided, and a filter is provided between the auxiliary kettle and the cleaning kettle; a fluid inlet and a fluid outlet of the supercritical fluid circulation device are connected to the auxiliary kettle and the cleaning kettle respectively. Connected.

The surfactant includes one or more of diisooctyl succinate sodium sulfonate, sodium dodecyl sulfonate, anhydrous sorbic acid fatty acid ester, and glyceryl monostearate. The concentration of surfactant is 0.01~30g/L.

The cleaning liquid includes one or more of detergent base dry powder, sodium perborate, and tetraacetylethylenediamine, and the concentration of the detergent in the working liquid is 0.1g/L~20g/L.

The auxiliary agent includes one or more of inorganic salts, emulsifiers, water softeners, and sodium stearate, and the concentration of the auxiliary agent in the working fluid is 0.01g/L~10g/L.

The solvent includes one or more of water, absolute ethanol, n-butanol, n-pentanol, n-hexanol, and n-heptanol.

The invention provides a method for cleaning mixed oil stains on textiles using supercritical fluid. The time for preliminary cleaning and fine cleaning under supercritical fluid conditions is 30 to 300 minutes.

The invention provides a method for cleaning mixed oil stains on textiles using supercritical fluid. The cleaned supercritical fluid is decompressed and separated, and the cleaning liquid, mixed oil stains and supercritical fluid are recovered.

The textiles of the present invention include cotton, wool, cashmere, goat hair, nylon, and polyester; the mixed oil stains include soy sauce, edible oil, liquid paraffin, palmitic acid, squalene, olive oil, and triolein. The supercritical fluid includes supercritical carbon dioxide fluid, supercritical methane fluid, supercritical ethane fluid, and supercritical propane fluid.

The present invention utilizes the characteristics of supercritical _CO2 with low viscosity, small surface tension and large transmission rate to dissolved objects, and applies it to dissolve surface contaminants of materials. The principle of the invention is: with the help of hydrophobic supercritical carbon dioxide medium as the continuous phase, and adding surfactant to the working fluid, the purpose is to reduce the surface tension of the liquid and facilitate the formation of microemulsion; the solvent in the working fluid is used Provide microemulsion core to enhance the polarity of supercritical fluid to form a supercritical carbon dioxide microemulsion system (W/SCF-CO ₂ ) carrying cleaning agent (SCF-CO ₂ /AOT/water/ethanol/cleaning agent microemulsion system ) method is green, environmentally friendly, and pollution-free. The selected cleaning agents have similar optimal cleaning processes, and have less environmental pollution and less damage to fabrics. In appropriate proportions, optimal cleaning can be achieved. Effect, and CO ₂ is a recyclable and renewable resource. It is rich in resources, cheap, safe, and comes from a wide range of sources, which is in line with the current theme of green and environmentally friendly development. During the cleaning process of materials, it has the advantages of not reacting with materials, excellent wettability, high diffusivity, easy to enter the interior of the material to be washed to remove dirt from dead corners, no need for drying, and no residue. Therefore, supercritical CO ₂ can replace VOCs and CFCs. As a cleaning agent. No industrial waste is produced during the cleaning process, there is no residue after cleaning, no secondary drying is required, and it can be recycled and reused. It has good safety, low cost, wide source, and is environmentally friendly, so it has broad application prospects in industrial production.

Compared with the prior art, the beneficial effects of the present invention are:

1. The present invention provides a method for cleaning contaminated textiles in supercritical fluids. The cleaning agent is mixed with an appropriate amount of surfactants and organic alcohols to form a working fluid, and then the working fluid is used in situ using a hydrophobic supercritical fluid medium. Microemulsions are formed, and the microemulsions pass through the contaminated textiles with the fluid to achieve cleaning processing in supercritical fluids. At the same time, they can also phase separate and remove pollutants in the fluid and micro-water environment, and have strong decontamination ability; the fluid is circulated during the circulation process , the micro-emulsion shell that releases the cleaning fluid is re-formed in situ on the outer surface of the textile or the outer surface of the contaminated micro-emulsion, and then the mixed oil stains on the textile are transferred into the fluid again; and then pure supercritical fluid is used for cleaning. It can further clean contaminated textiles and clean various additives used in the first step, with good decontamination effect.

2. The cleaning method provided by the present invention is simple in process and easy to operate, and the chemicals and fluid media used can be recycled and reused. On the basis of solving the problems of cumbersome process flow and high energy consumption in the existing technology, it also combines the traditional Water washing is changed to ecological, green and environmentally friendly supercritical fluid dry cleaning, which is in line with the concept of green and sustainable development.

Description of the drawings

Figure 1 is a schematic structural diagram of a supercritical carbon dioxide fluid cleaning system utilized in an embodiment of the present invention;

Figure 2 is a schematic structural diagram of a high-pressure cleaning cylinder for supercritical carbon dioxide fluid provided by an embodiment of the present invention;

Figures 3 and 4 are respectively electron microscope scanning images of cotton fabrics and nylon fabrics before, after, and after cleaning according to the embodiment of the present invention.

Explanation of reference symbols:

1. _CO2 storage tank; 2, 6, 9, 11, 13, 14, 21 and 22. Valves; 3. Condenser; 4. Booster pump; 5. Heat exchanger; 7. Auxiliary unit; 8. Filtration 10. High-pressure reactor; 12. Circulation pump; 15 and 17. Pressure gauge; 16 and 18 thermometer; 19. Separator; 20. Purifier; 23. Circulating fluid inlet; 24. Insulation layer; 25. Fluid distribution 26. Porous filter plate; 27. Fluid guide cover; 28. Area to be treated; 29. Porous shaft; 30. Circulating fluid outlet; 31. Additive kettle; 32. Autoclave.

Implementation

Specific implementations of the present invention will be described in further detail below with reference to examples.

The following embodiments of the present invention provide a method for cleaning mixed oil stains on textiles using supercriticality. The method mainly utilizes the supercritical carbon dioxide fluid treatment system shown in Figure 1 and the supercritical carbon dioxide fluid high-pressure finishing cylinder shown in Figure 2 accomplish.

Referring to Figure 1, the supercritical carbon dioxide fluid treatment system consists of a pressurizing system, a cleaning circulation system and a separation and recovery system. Among them, the pressurized system is that the CO ₂ storage tank 1 is first connected to the stop valve 2, the condenser 3, the pressurizing pump 4, the preheater 5, the stop valve 6, and the stop valve 13 through pipelines, and then through the stop valve 14. The inlet of the high-pressure finishing cylinder 10 is connected; the outlet of the high-pressure reaction kettle 10 is connected to the stop valve 11 to control the fluid entering the separation recovery system and the treatment circulation system; the auxiliary unit 7 is connected to the high-pressure finishing cylinder 10 through the filter 8 and the stop valve 9. And its top is equipped with thermometers 16, 19 and pressure gauges 17, 20. The separation and recovery system includes a stop valve 11, a separation kettle 19, and a purifier 20 connected through pipelines, and finally recovers the fluid to the condenser 3.

Referring to Figure 2, the supercritical carbon dioxide fluid high-pressure cleaning kettle includes an auxiliary kettle 31; the tubular fluid distributor 25 in the cylindrical auxiliary kettle 31 is mainly composed of three interconnected pipes, of which the ones on both sides The two pipes are circulating fluid outlet pipes, with their pipe mouths facing downward and below the liquid level of the working fluid in the auxiliary kettle 31. The bottom end of the middle pipe is the fluid circulation inlet 23, which is connected with the fluid treatment system with the circulation pump 12 ( The auxiliary unit 7 in Figure 1) is connected; the top of the working kettle 31 is the circulating fluid outlet 30, which is connected to the high-pressure finishing cylinder 10 in the fluid treatment system (Figure 1); the porous shaft 29 in the working kettle 32 , can effectively filter impurities contained in the working fluid and circulating fluid; a porous filter 26 with a porous structure is provided between the auxiliary kettle 31 and the working kettle 32, and the fluid guide cover 27 above it communicates with the fluid through the pipe body The circulation outlet 30 is connected. When the supercritical carbon dioxide fluid passes through the auxiliary kettle 31, the working fluid is brought out, and enters the tube body through the filter 26 and the fluid guide cover 27. At this time, the supercritical carbon dioxide fluid and the working fluid pass through the porous shaft to treat the fabric or other products Cleaning is carried out, and finally flows out of the working kettle 32 through the circulating fluid outlet 30.

Example 1

This embodiment provides a mixed oil stain cleaning method using supercritical fluid as the medium. The textile samples are cotton fabrics and nylon fabrics contaminated by mixed oil stains. The above device is used, including the following steps:

(1) Dissolve 1.0g sodium bis(2-ethylhexyl)succinate sulfonate in 20mL absolute ethanol, stir evenly until completely dissolved, add 30mL cleaning agent (40% detergent base dry powder, 35% perboric acid Sodium and 5% tetraacetylethylenediamine), stir evenly to prepare a working solution.

(2) Place the working fluid in the additive kettle 31. Roll a 30cm×30cm cotton or nylon contaminated fabric into a cylinder and load it into the treatment area 29 in the working kettle 32. The auxiliary kettle 31 and the treatment area 29 are sealed and connected to form a supercritical carbon dioxide cleaning device to ensure that the treatment area is 29 Keep a distance of 45cm from the working fluid surface to prevent direct contact between the mixed working fluid and contaminated fabrics due to fluid entrainment, resulting in a large amount of moisture; then connect the device to a supercritical carbon dioxide fluid treatment system with a circulation device .

(3) Charge CO ₂ into the closed high-pressure reactor 10, and clean cotton or nylon contaminated fabrics under the conditions of temperature 70°C, pressure 20MPa, fluid dynamic and static circulation time ratio 2min:3min, and processing time 60min. The specific operation is as follows: start the circulation pump 12 in the supercritical carbon dioxide fluid treatment system, so that the circulating fluid fully contacts the working fluid through the tubular fluid distributor 25 in the auxiliary kettle 31, and under the action of the formed microemulsion, the working fluid is The cleaning components in the working fluid are transferred to the hydrophobic fluid, and then flow into the treatment area 29, and fully interact with the mixed oil stains on the contaminated fabric through the through holes. The circulating fluid carries the effective cleaning components in the working fluid and is forced to pass through the washed Textiles and released on the textiles, a degradation or emulsification reaction occurs between the cleaning fluid and the oil stains, reducing the force between the oil stains and the fibers, forming a stained microemulsion in situ on the outer surface or outer surface of the textiles. The stained microemulsions The emulsion separates from the textiles under the physical action of the supercritical fluid, completing the preliminary cleaning treatment of textiles containing mixed oil stains.

(4) After cleaning, the supercritical carbon dioxide flows into the separation kettle 19 and the purifier 20 to separate and recover the residual working fluid, and depressurize the supercritical carbon dioxide fluid treatment system to reduce the pressure in the system to atmospheric pressure.

(5) Take out the auxiliary kettle and the remaining working fluid, follow the method of step (3), pass in pure CO ₂ , clean the fabric again, remove the remaining working fluid on the textile, and then clean the supercritical carbon dioxide fluid treatment system Depressurize, depressurize the supercritical carbon dioxide fluid treatment system, and finally remove the cleaned fabric samples.

(5) After taking out the cotton or nylon fabric from the device, measure the whiteness, wool effect and other indicators of the treated contaminated fabric.

Test the cleaned cotton and nylon fabric samples. Whiteness, decontamination efficiency, and decontamination ratio are the main indicators to measure the washing effect. The test methods are as follows:

Refer to GB/T 13174-2021 "Determination of Detergency and Cycle Washing Performance of Detergents for Clothing" to test the whiteness of contaminated cotton fabric samples and calculate the stain removal ratio; use WSB-3A d/o intelligent digital whiteness Use a meter to measure the whiteness of the fabric after washing, take the average value of ten measurements, and calculate the stain removal ratio according to formula (1).

(1)

In the formula:

P: Decontamination ratio

R ₁ : Decontamination ratio after sample cleaning

R ₀ : Decontamination ratio after standard washing

W ₁ : Whiteness before cleaning

W ₂ : Whiteness after cleaning

Refer to GB/T 8629-2017 "Household Washing and Drying Procedures for Textile Testing" to test the weight loss rate of washed cotton samples and calculate the decontamination efficiency according to formula (2).

(2)

In the formula:

A: Decontamination efficiency of the sample

m ₀ : mass before pollution, unit is grams (g)

m ₁ : mass after pollution, unit is grams (g)

m ₂ : mass after cleaning, unit is grams (g)

The test results were obtained. The test results of the fat content and whiteness of contaminated fabrics after supercritical fluid cleaning are shown in Tables 1 and 2.

Refer to Figures 3 and 4, which are electron microscope scanning images (500×) of cotton fabrics and nylon fabrics before, after, and after cleaning in this embodiment.

In Figure 3, picture a shows the original cotton fabric, picture b shows the cotton fabric after mixed oil pollution; picture c shows the cotton fabric after supercritical fluid cleaning; in Figure 4, picture a shows the original nylon fabric, and picture b shows the mixed oil pollution. Nylon fabric after pollution; Picture c shows the nylon fabric after cleaning with supercritical fluid. It can be seen from Figure 3 and Figure 4 (a) that the original surface texture of cotton and nylon fabrics without any treatment is clear, and the fibers and fiber gaps on the fabrics are clearly visible; while Figure (b) shows that compared with untreated cotton and nylon fabrics, , after the cotton and nylon fabrics were contaminated by mixed oil stains, the original lines, interweaving points, fibers and fiber gaps were covered, and the dents on the fabric surface became shallower; and Figure c shows that after cleaning with supercritical fluid, the surface of cotton and nylon fibers The original texture and interweaving of warp and weft are gradually highlighted, the fibers and their gaps become clearly visible, and the fiber surface becomes cleaner. Indicates that a large amount of stains covering the fiber surface have been removed. By comparing pictures a and c in Figures 3 and 4, it can be found that supercritical fluid cleaning does not cause obvious damage to the surface morphology of cotton and nylon fibers, and is less destructive to the fabric, while its gloss is improved.

Example 2:

This embodiment provides a cleaning method for contaminated fabrics in supercritical fluid. The cleaning method is basically the same as the method described in Embodiment 1. The difference is that in this embodiment, in step (1), bis(2-ethylhexyl) ) The dosage of sodium succinate sulfonate is 0.4g. The test results of this embodiment are shown in Tables 1 and 2 respectively.

Example 3:

This embodiment provides a cleaning method for contaminated fabrics in supercritical fluids. The cleaning method is basically the same as the method described in Embodiment 1. The difference is that in this embodiment, the amount of absolute ethanol used in step (1) is 40 mL. . The test results of this embodiment are shown in Tables 1 and 2 respectively.

Example 4:

This embodiment provides a cleaning method for contaminated fabrics in supercritical fluid. The cleaning method is basically the same as the method described in Embodiment 1. The difference is that in this embodiment, the cleaning agent in step (1) is 45%. Detergent base dry powder, 45% sodium perborate and 10% tetraacetylethylenediamine. The test results of this embodiment are shown in Tables 1 and 2 respectively.

Example 5:

This embodiment provides a cleaning method for contaminated fabrics in supercritical fluid. The cleaning method is basically the same as the method described in Embodiment 1. The difference is that in step (3) of this embodiment, the pressure is 8MPa. The test results of this embodiment are shown in Tables 1 and 2 respectively.

Example 6:

This embodiment provides a cleaning method for contaminated fabrics in supercritical fluid. The cleaning method is basically the same as the method described in Embodiment 1. The difference is that the processing temperature in step (3) of this embodiment is 70°C. The test results of this embodiment are shown in Tables 1 and 2 respectively.

Example 7:

This embodiment provides a cleaning method for contaminated fabrics in supercritical fluid. The cleaning method is basically the same as the method described in Embodiment 1. The difference is that the processing time in step (3) of this embodiment is 30 minutes. The test results of this embodiment are shown in Tables 1 and 2 respectively.

Example 8:

This embodiment provides a cleaning method for contaminated fabrics in supercritical fluid. The cleaning method is basically the same as the method described in Embodiment 1. The difference is that in this embodiment, the fluid dynamic and static circulation time ratio in step (3) is 4 minutes: 1min, the test results of this embodiment are shown in Tables 1 and 2 respectively.

As shown in Tables 1 and 2, the cotton sample achieved good whiteness effect after cleaning, with a decontamination ratio of 0.9355 and a decontamination efficiency of 97.92%; the nylon sample had a decontamination ratio of 0.9432 and a decontamination efficiency of 99.75 %. Conditions such as temperature, pressure, processing time and detergent dosage have a significant impact on the cleaning effect of contaminated cotton fabrics. With the increase of pressure and the extension of processing time, the cleaning effect of the samples is continuously improved.

Table 1 Cleaning effect of cotton fabrics

.

Table 2 Nylon cleaning effect

.

Claims (10)

1. A method for cleaning mixed oil stains on textiles by using supercritical fluid, which is characterized by comprising the following steps:

(1) Preparing working solution for cleaning mixed oil stains on textiles by supercritical fluid, wherein the working solution comprises a surfactant, a cleaning solution, an auxiliary agent and a solvent;

(2) Forming a water-in-supercritical fluid microemulsion in situ in the supercritical fluid, carrying the working fluid by using the microemulsion, and carrying out forced circulation and static control on the fluid by adopting a circulating pump under the conditions of the temperature of 10-130 ℃ and the pressure of 7-40 MPa, wherein the ratio of the circulation time to the static time is (10-1) min for 1min; the circulating fluid carries effective cleaning components in the working solution to forcedly pass through the washed textile and is released on the textile, degradation or emulsification reaction occurs between the cleaning solution and the greasy dirt, the acting force between the greasy dirt and the fiber is reduced, and a dirty microemulsion is formed in situ on the outer surface or the outer surface of the textile, and the dirty microemulsion is separated from the textile under the physical action of the supercritical fluid, so that the textile containing mixed greasy dirt is primarily cleaned;

(3) And (3) carrying out fine cleaning on the textile subjected to the preliminary cleaning in the step (2) by adopting pure supercritical fluid under the conditions that the temperature is 30-120 ℃ and the pressure is 5-35 MPa, and removing residual working fluid on the textile to obtain the clean textile.

2. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: placing the working solution and the textile containing the mixed oil stain into a high-pressure reaction kettle, wherein the high-pressure reaction kettle is communicated with a supercritical fluid circulation device; the high-pressure reaction kettle comprises an auxiliary agent kettle and a cleaning kettle, wherein the auxiliary agent kettle is used for storing cleaning liquid, the upper part of the auxiliary agent kettle is communicated with the cleaning kettle, a yarn cage is arranged in the cleaning kettle, textiles containing mixed oil stains are arranged in the yarn cage, a plurality of through holes are formed in the yarn cage, and a filter is arranged between the auxiliary agent kettle and the cleaning kettle; and the fluid inlet and the fluid outlet of the supercritical fluid circulation device are respectively communicated with the auxiliary agent kettle and the cleaning kettle.

3. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: the surfactant comprises one or more of diisooctyl succinate sodium sulfonate, sodium dodecyl sulfonate, sorbitan fatty acid ester and glycerin monostearate, and the concentration of the surfactant in the working solution is 0.01-30 g/L.

4. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: the cleaning liquid comprises one or more of detergent base dry powder, sodium perborate and tetraacetyl ethylenediamine, and the concentration of the detergent in the working liquid is 0.1 g/L-20 g/L.

5. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: the auxiliary agent comprises one or more of inorganic salt, emulsifying agent, water softening agent and sodium stearate, and the concentration of the auxiliary agent in the working solution is 0.01 g/L-10 g/L.

6. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: the solvent comprises one or more of water, absolute ethyl alcohol, n-butanol, n-amyl alcohol, n-hexanol and n-heptanol.

7. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: the time for preliminary cleaning and fine cleaning under the supercritical fluid condition is 30-300 min.

8. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: and (3) carrying out reduced pressure separation on the cleaned supercritical fluid, and recovering the cleaning fluid, the mixed greasy dirt and the supercritical fluid.

9. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: the textile comprises cotton, wool, cashmere, goat hair, chinlon and terylene; the mixed greasy dirt comprises soy sauce, edible oil, liquid paraffin, palmitic acid, squalene, olive oil and triolein.

10. A method of cleaning mixed oil stains on textiles using supercritical fluid according to claim 1, wherein: the supercritical fluid comprises supercritical carbon dioxide fluid, supercritical methane fluid, supercritical ethane fluid and supercritical propane fluid.