Acidic ionic liquid catalyst, preparation method and application of acidic ionic liquid catalyst in degradation of waste textiles

Abstract

The invention provides an acidic ionic liquid catalyst, a preparation method and application of the acidic ionic liquid catalyst in degradation of waste textiles, relates to the technical field of catalysts, and designs a disulfonic acid metal-based ionic liquid catalyst with Bronsted-Lewis dual acidity. The problems of secondary pollution and the like caused by the fact that a traditional catalyst is toxic and difficult to separate and residues cause products with colors which cannot be removed in recycling of waste polyester cotton textiles are solved, the conversion rate of polyester fibers is increased while cotton fibers are separated out, and considerable economic benefits are obtained.

Description

Technical Field

[0001] The invention relates to the relevant field of catalysts, and in particular to an acidic ionic liquid catalyst, a preparation method and application thereof in degrading waste textiles. Background Art

[0002] Polyester-cotton textiles are textiles blended from polyester fibers (polyethylene terephthalate, PET) and cotton fibers (mainly cellulose). Polyester-cotton textiles have the advantages of high strength and good wear resistance of polyester fibers, as well as good water and sweat absorption and high comfort of cotton fibers. Therefore, they are widely used in clothing, home textiles, industrial production and other fields. However, due to the huge amount of waste from the use of polyester-cotton textiles, many waste polyester-cotton textiles are treated by incineration and landfill. The burning of waste polyester-cotton textiles will produce a large amount of toxic substances, causing air pollution, while landfilling is difficult for natural microorganisms to degrade and will cause land pollution. Therefore, the effective recycling of polyester-cotton textiles is crucial to the creation of a circular economy.

[0003] At present, the recycling and reuse of waste polyester-cotton textiles is divided into physical and chemical methods. The physical method is to recycle and reuse waste polyester through disinfection, classification, crushing, yarn formation and other processes under the premise of retaining the basic chemical molecular characteristics. The physical recycling method has many separation steps and low efficiency, and the separated fibers can only be used to generate low value-added products. The chemical method is mainly divided into two categories, one is to dissolve cotton fibers into oligomers or glucose, and the other is to depolymerize polyester fibers into monomer compounds. Since polyester fibers are the main component of polyester-cotton textiles, accounting for 60%-90% of the main components of polyester-cotton textiles, the depolymerization reaction of the catalyst is used to selectively degrade the polyester fibers in polyester-cotton textiles, so that the unreacted cotton fibers are completely separated from them. The degradation products can be directly used as raw materials for synthetic polymers, or they can be converted into other useful chemical intermediates without any disadvantages encountered in other recycling methods. The resulting polymers have the same properties and have certain tolerance to pollutants. However, traditional catalysts such as inorganic strong acids and bases, metal acetates, metal oxides, etc. are toxic, difficult to separate, and have secondary pollution caused by residues that cannot be removed. Therefore, finding a suitable catalyst for the degradation reaction has always been a research focus and difficulty. Summary of the invention

[0004] The purpose of the embodiments of the present invention is to propose an acidic ionic liquid catalyst, a preparation method and its application in degrading waste textiles, so as to alleviate the technical problems existing in the prior art that traditional catalysts are toxic, difficult to separate and residues cause secondary pollution of the product with color that cannot be removed in the recycling of waste polyester-cotton textiles.

[0005] To solve the above technical problems, the embodiments of the present invention provide the following technical solutions:

[0006] The first aspect of the present invention provides an acidic ionic liquid catalyst, the structural part of the catalyst comprises: a Lewis acidic anion group and Acidic triethylenediamine disulfonic acid cation group; the structural formula is shown below.

[0007]

[0008] Among them, X is Cl, Br, I, and M is Zn, Al, Fe, Cu.

[0009] In some variations of the first aspect of the present invention, -Lewis bis-acidic bis-sulfonic acid metal-based ionic liquid catalyst.

[0010] In a second aspect, the present invention further provides a method for preparing an acidic ionic liquid catalyst, which is used to prepare the acidic ionic liquid catalyst described above, and is characterized in that:

[0011] S10. 1,3-propane sultone is added to a triethylenediamine solution with ethyl acetate as a protective solvent, the reaction temperature is 60-90°C, the reaction time is 48h, after the reaction is completed, the filter cake is filtered under reduced pressure, washed with ethyl acetate 3-5 times, and dried at 60-80°C to obtain a white powder intermediate I;

[0012] S20. Slowly add a dilute hydrochloric acid solution to the aqueous solution of intermediate Ⅰ, the first stage reaction temperature is controlled at 20-30 ℃, the reaction time is controlled at 30-60min, the second stage is heated to 60-80 ℃, the reaction time is controlled at 6-8h, after the reaction is completed, the reaction is rotary evaporated and vacuum dried to obtain intermediate Ⅱ;

[0013] S30. Under N2 protection, add Cl-based Lewis acid metal salt to the molten intermediate II, control the reaction temperature at 60-90°C, and control the reaction time at 6-8h to obtain -Lewis bis-acidic bis-sulfonic acid metal-based ionic liquid catalyst.

[0014] In some modified embodiments of the second aspect of the present invention, the molar ratio of triethylenediamine to sulfonic acid group in step S10 is 1:2.

[0015] In some modified embodiments of the second aspect of the present invention, the molar ratio of the hydrochloric acid solution to the aqueous solution of intermediate I in step S20 is 2:1.

[0016] In some modified embodiments of the second aspect of the present invention, the molar ratio of the Cl-based Lewis acidic metal salt to the intermediate II in step 30 is 2:1.

[0017] In some modified embodiments of the second aspect of the present invention, the complex catalytic performance of the triethylenediamine functionalized cationic group containing a disulfonic acid group and a Lewis acidic metal active site species.

[0018] In some variations of the second aspect of the invention, the sulfonic acid group is an alkylsulfonic acid.

[0019] In some modified embodiments of the second aspect of the present invention, the solvent of the sulfonic acid group solution is one of ethyl acetate, propyl acetate, butyl acetate, and n-propyl acetate.

[0020] In a third aspect, the present invention provides an application of an acidic ionic liquid catalyst, wherein the acidic ionic liquid catalyst described above is used for the degradation reaction of waste textiles.

[0021] The present invention provides an acidic ionic liquid catalyst, a preparation method and its application in degrading waste textiles, and designs -Lewis double acidic double sulfonic acid metal-based ionic liquid catalyst solves the problems of traditional catalyst toxicity, difficulty in separation, and residues causing secondary pollution of products with irremovable color in the recycling of waste polyester-cotton textiles. It improves the conversion rate of polyester fibers while separating cotton fibers, and obtains considerable economic benefits.

[0022] (1) Introduction of Lewis acid metal salts and The acidic functional groups achieve synergistic catalytic effects through complexation with Z bonds. -Lewis double acid type center exists, by adjusting the acid strength and the distance of the acid center and other factors, it can provide cations and accept electron pairs, and polarize the solvent and reactants under their synergistic effect, and improve their reaction activity, so as to better catalyze the depolymerization reaction of different types of polyesters.

[0023] (2) This catalyst is based on ionic liquids, which have a vapor pressure of zero and can be used for reactions under vacuum and high pressure conditions. It is not easy to burn, explode, or oxidize, and has good thermal and chemical stability.

[0024] (3) The amount of catalyst used is small, the conversion rate of reactants is high, and it is highly efficient, which significantly reduces production costs.

[0025] (4) The catalyst cycle efficiency is high, which can achieve the recycling of catalyst while ensuring high selectivity and conversion rate, significantly reducing production costs.

[0026] (5) The degradation rate of polyester fiber reached 90.8%, realizing the recycling and reuse of polyester-cotton textiles and breaking through the barriers of existing technologies. BRIEF DESCRIPTION OF THE DRAWINGS

[0027] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required to be used in the embodiments are briefly introduced below.

[0028] Figure 1 A diagram showing the reaction mechanism of the acidic ionic liquid catalyst provided by the present invention in waste textiles;

[0029] Figure 2 A schematic diagram of the synthesis of the acidic ionic liquid catalyst intermediate I provided by the present invention;

[0030] Figure 3 A schematic diagram of the synthesis of the acidic ionic liquid catalyst intermediate II provided by the present invention;

[0031] Figure 4 A schematic diagram of the synthesis of a product catalyst in the method for preparing an acidic ionic liquid catalyst provided by the present invention;

[0032] Figure 5 The infrared spectrum of the catalyst product obtained by using the acidic ionic liquid catalyst provided in the embodiment of the present invention;

[0033] Figure 6 Product catalyst for the application of the acidic ionic liquid catalyst provided in the embodiment of the present invention in the degradation of waste textiles 1 H NMR spectrum;

[0034] Figure 7 A schematic diagram of the synthesis of a bissulfonic acid metal-based ionic liquid catalyst, a product of the method for preparing an acidic ionic liquid catalyst provided by the present invention;

[0035] Figure 8 BHET infrared spectrum of the degradation product of the acidic ionic liquid catalyst provided in the embodiment of the present invention when used in the degradation of waste textiles. DETAILED DESCRIPTION

[0036] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0037] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention.

[0038] The present invention is further described in detail below by way of examples. Through these descriptions, the features and advantages of the present invention will become more clear and distinct.

[0039] like Figure 1-4 The present invention relates to an acidic ionic liquid catalyst, a preparation method and its application in degrading waste polyester-cotton textiles (80% PET-20% cotton). The catalyst is composed of Lewis acidic anion groups and An acidic metal-based ionic liquid catalyst system composed of acidic triethylenediamine disulfonic acid cationic groups can improve its reaction activity by adjusting factors such as acid strength and the distance of the acid center, thereby further improving the catalytic efficiency. At the same time, the triethylenediamine functionalized cationic group containing disulfonic acid groups can be synthesized and modified with different Lewis acid salts, thereby changing the acidity of the entire molecule to meet the catalytic molecules of the reaction conditions. It is used to solve the problems of traditional catalysts being toxic, difficult to separate, and residues causing secondary pollution of products with colors that cannot be removed in the recycling and reuse of waste polyester-cotton textiles. At the same time, it can greatly improve the conversion rate of polyester fiber degradation and obtain considerable economic benefits.

[0040] The advantage of acidic ionic liquid catalysts is that the introduction of disulfonic acid groups on the cationic groups has a catalytic effect that is superior to the catalytic effect of the monosulfonic acid groups on the cationic groups under the synergistic effect with the Lewis acidic anionic groups. The type of metal salt can be changed to change different catalytic effects, and different catalytic effects can be changed for different types of polyesters to form a catalytic system.

[0041] The degradation reaction mechanism of the present invention is: under the action of acidic ionic liquid catalyst, hydroxyl oxygen in water or alcohol nucleophilically attacks carbonyl carbon in PET chain. After the carbonyl oxygen is attacked, elimination reaction occurs, macromolecular chain breaks, and different small molecules are generated to complete depolymerization reaction.

[0042] An acidic ionic liquid catalyst, the structural part of the catalyst comprises: a Lewis acidic anion group and Acidic triethylenediamine disulfonic acid cation group.

[0043] According to the principles of the present invention, the preparation method of the acidic ionic liquid catalyst is mainly divided into two steps, step 1: using a disulfonic acid functionalized triethylenediamine cationic group and a Lewis acidic anionic group of a disulfonic acid metal-based ionic liquid; triethylenediamine is inherently stable and has the characteristics of a synthetic reaction site, and the introduction of a disulfonic acid group into the cationic group provides a promoting effect for catalysis; step 2: using a dilute HCl solution with a concentration of 1 mol / L to acidify the intermediate I to obtain the intermediate II. Step 3: using a Cl-based Lewis acidic metal salt and the intermediate II described in step 2 to prepare an acidic ionic liquid catalyst system. The details are as follows:

[0044] A method for preparing an acidic ionic liquid catalyst,

[0045] (1) adding 1,3-propane sultone to a triethylenediamine solution with ethyl acetate as a protective solvent, the reaction temperature is 60-90°C, the reaction time is 48 hours, after the reaction is completed, the filter cake is filtered under reduced pressure, washed with ethyl acetate 3-5 times, and dried at 60-80°C to obtain a white powder intermediate I;

[0046] (2) slowly adding a dilute hydrochloric acid solution to the aqueous solution of intermediate I, the first stage reaction temperature is controlled at 20-30°C, the reaction time is controlled at 30-60 min, the second stage temperature is raised to 60-80°C, the reaction time is controlled at 6-8 h, after the reaction is completed, the mixture is subjected to rotary evaporation and vacuum drying to obtain intermediate II;

[0047] (3) Under N2 protection, a Cl-based Lewis acidic metal salt is added to the molten intermediate II, the reaction temperature is controlled at 60-90°C, and the reaction time is controlled at 6-8h to obtain an acidic ionic liquid catalyst.

[0048] According to the principles of the present invention, the cationic group in the present invention can be one of triethylenediamine, 1-methylimidazole, 2-methylimidazole, etc., preferably triethylenediamine. The sulfonic acid group can be one of methylsulfonic acid, alkylsulfonic acid, alkylbenzenesulfonic acid, etc., preferably alkylsulfonic acid. The solvent of the sulfonic acid group solution can be one of ethyl acetate, propyl acetate, butyl acetate, n-propyl acetate, etc., preferably ethyl acetate. The Lewis acidic metal salt is one of ZnCl2, FeCl3, AlCl3, etc., preferably ZnCl2. The above reagents combined with the method of the present invention can also prepare the acidic ionic liquid catalyst proposed by the present invention.

[0049] The invention discloses an application of an acidic ionic liquid catalyst, wherein the catalyst is applied to degradation reaction of polyester-cotton textiles.

[0050] The application method is as follows:

[0051] Under the protection of N2, weigh 1-5g of waste textiles, preferably 3g; weigh 10-30g of ethylene glycol, preferably 27g; weigh 0.2-1.0g of bis-acid ionic liquid catalyst, preferably 0.6g; mix, the reaction temperature is controlled at 120-200℃, preferably 190℃; the reaction time is controlled at 4-10h, preferably 6h. After the reaction is completed, filter the reaction solution while hot, wash the filter cake with distilled water and dry it to obtain the mass of cotton and unreacted polyester fiber. Under the action of the bis-sulfonic acid metal-based ionic liquid catalyst, the hydroxyl oxygen in water or alcohol nucleophilically attacks the carbonyl carbon in the polyester PET chain. After the carbonyl oxygen is attacked, an elimination reaction occurs, the macromolecular chain breaks, and different small molecules are generated to complete the depolymerization reaction.

[0052] Example 1

[0053] The preparation method of the -Lewis bis-acidic bis-sulfonic acid metal-based ionic liquid catalyst is as follows:

[0054] (1) 1,3-propane sultone was added to a triethylenediamine solution with ethyl acetate as a protective solvent. The reaction temperature was 80°C and the reaction time was 48 hours. After the reaction was completed, the filter cake was filtered under reduced pressure and washed with ethyl acetate for 3 times. After drying at 60°C, a white powdery intermediate I was obtained. The reaction formula is as follows: Figure 2 ) as shown.

[0055]

[0056] (2) Dissolve an appropriate amount of intermediate I in an appropriate amount of distilled water at room temperature, slowly add dilute hydrochloric acid at a rate of 20-100 ml / s, stir magnetically at room temperature for 1 hour, then heat to 80°C and continue to stir magnetically, and condense and reflux under nitrogen protection for 8 hours. After the reaction is completed, rotary evaporation and vacuum drying are performed to obtain a white liquid product intermediate II, the reaction formula is as follows ( Figure 3 ) as shown.

[0057]

[0058] (3) Under N2 protection, 0.01 mol of intermediate II was heated until it was completely melted, and then 0.02 mol of ZnCl2 was added, and the mixture was stirred and reacted at the same temperature. The mixture was then heated to 90°C and magnetic stirring was continued and the mixture was refluxed under condensation for 6 h. After the reaction was completed, the mixture was subjected to rotary evaporation and vacuum drying at 60°C for 24 h to obtain a disulfonic acid metal-based ionic liquid catalyst, as follows ( Figure 4 ) as shown.

[0059]

[0060] The structural formula of the bissulfonic acid metal-based ionic liquid catalyst of Example 1 is as follows:

[0061]

[0062] The infrared spectrum of the bissulfonic acid metal-based ionic liquid catalyst of Example 1 is 1 H NMR spectrum is shown as ( Figure 5 , Figure 6 ) as shown.

[0063] The general preparation formula of the bissulfonic acid metal-based ionic liquid catalyst of Example 1 is as follows: Figure 7 ) as shown:

[0064]

[0065] Example 2

[0066] Add 3.0g polyester-cotton textile, 27g ethylene glycol, 0.6g acidic catalyst prepared in Example 1 (2% of raw material dosage) into a three-necked flask, and heat the reactor to 190°C for 6h. After the reaction, filter the reaction solution while hot, wash the filter cake with distilled water and dry it to obtain the mass of cotton and unreacted polyester fiber. Add about 400ml of distilled water to the filtrate, heat and stir to dissolve, filter to remove insoluble oligomers in the filtrate, concentrate the filtrate to 100ml by rotary evaporation, and place it in a refrigerator at 3°C ​​for 8 hours. The degradation product BHET crystallizes and precipitates. After filtering, vacuum dry at 60°C and weigh to obtain the product BHET. The filtrate is distilled at 120°C to remove water and ethylene glycol to recover the ionic liquid catalyst. The infrared spectrum of the degradation product BHET is as follows ( Figure 8 ), the calculated yield of the degradation product BHET was 76.62%.

[0067] Example 3

[0068] Under the same conditions as in Example 2, the monoacidic [DA-2PS][Cl]2 was used to replace the disulfonic acid metal-based ionic liquid catalyst of the present invention, and the BHET yield was calculated to be 15.23% without changing the reaction time, temperature and other conditions.

[0069] Example 4

[0070] Under the same conditions as in Example 2, monoacidic ZnCl2 was used to replace the disulfonic acid metal-based ionic liquid catalyst of the present invention, and the BHET yield was calculated to be 30.14% when the reaction time, temperature and other conditions were not changed.

[0071] Example 5

[0072] Under the same conditions as in Example 2, without adding any catalyst, and without changing the reaction time, temperature and other conditions, the BHET yield was calculated to be 0%.

[0073] Comparison 1: Compared with implementation case 2, only the reaction time was changed to 3h;

[0074] Comparison 2: Compared with implementation case 2, only the amount of catalyst was changed, and the catalyst accounted for 10%.

[0075] The catalytic performances of Examples 2 to 5 and Comparative 1 and Comparative 2 are compared, as shown in Table 1.

[0076] Table 1 Comparison of catalytic performance of ionic liquids

[0077] project Example 2 Example 3 Example 4 Example 5 Comparison 1 Comparison 2 Ratio of reactants 1:09 1:09 1:09 1:09 1:09 1:09 Catalyst ratio 20％ 20％ 20％ 0％ 20％ 10％ Reaction temperature 190℃ 190℃ 190℃ 190℃ 190℃ 190℃ Reaction time 6h 6h 6h 6h 3h 6h BHET yield 76.62％ 15.23％ 30.14％ 0％ 26.23％ 42.12％

[0078] It can be seen from Table 1 that the yield of BHET obtained by degrading polyester PET using the acidic ionic liquid catalyst of the present invention can reach 76.62%.

[0079] The present invention only selects the catalyst of Example 1 for comparison test. According to the principle of the present invention, other acidic ionic liquid catalysts also have the effect of degrading polyester-cotton textiles.

[0080] The catalytic performance of the catalysts without adding any catalyst, traditional catalysts Zn(OAc)2 and ZnCl2, disulfonic acid non-metallic ionic liquid catalyst [DA-2PS][Cl]2, imidazole sulfonic acid diacid ionic liquid catalysts [HO3S-(CH2)4-mim]Cl-ZnCl2, [HO3S-(CH2)3-mim]Cl-ZnCl2, and acidic ionic liquid catalyst [DA-2PS][FeCl3]2 synthesized by the method of the present invention were compared, as shown in Table 2 for details.

[0081] Table 2 Comparison of catalytic performance between ionic liquid catalysts and traditional catalysts

[0082] serial number Catalyst type PET alcoholysis rate BHET yield 1 - 0 0 2 <![CDATA[Zn(OAc)2]]> 66.06％ 52.12％ 3 <![CDATA[ZnCl2]]> 60.12％ 30.14％ 4 <![CDATA[[DA-2PS][Cl]2]]> 28.90％ 15.23％ 5 <![CDATA[[HO3S-(CH2)4-mim]Cl-ZnCl2]]> 85.68％ 70.50％ 6 <![CDATA[[HO3S-(CH2)3-mim]Cl-ZnCl2]]> 87.20％ 72.21％ 7 <![CDATA[[DA-2PS][ZnCl3]2]]> 90.80％ 76.62％

[0083] As can be seen from Table 2, the present invention compares the catalytic performance of ionic liquid catalysts with that of traditional catalysts, and finds that the degradation rate of polyester fiber by the acidic ionic liquid catalyst designed and synthesized by the present invention reaches 90.8%, achieving the actual economic benefits of recycling and reusing waste polyester-cotton textiles, and breaking through the barriers of the prior art.

[0084] It should be noted that the method used in this embodiment is applied to textiles other than polyester.

[0085] The present invention has been described above in conjunction with preferred embodiments, but these embodiments are only exemplary and serve only as an illustration. On this basis, the present invention may be subjected to a variety of substitutions and improvements, all of which fall within the scope of protection of the present invention.

[0086] The above are only specific embodiments of the present invention, but the protection scope of the present invention is not limited thereto. Any person skilled in the art who is familiar with the technical field can easily think of changes or substitutions within the technical scope disclosed by the present invention, which should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. An acidic ionic liquid catalyst, characterized in that: The catalyst structure includes: Lewis acid anion group and Acidic triethylenediamine disulfonic acid cation group; the structural formula is as follows: Among them, X is Cl, Br, I, and M is Zn, Al, Fe, Cu.

2. The acidic ionic liquid catalyst according to claim 1, characterized in that: have -Lewis bis-acidic bis-sulfonic acid metal-based ionic liquid catalyst.

3. A method for preparing an acidic ionic liquid catalyst, for preparing the acidic ionic liquid catalyst according to any one of claims 1 to 2, characterized in that: S10. 1,3-propane sultone is added to a triethylenediamine solution with ethyl acetate as a protective solvent, the reaction temperature is 60-90°C, the reaction time is 48h, after the reaction is completed, the filter cake is filtered under reduced pressure, washed with ethyl acetate 3-5 times, and dried at 60-80°C to obtain a white powder intermediate I; S20. Slowly add a dilute hydrochloric acid solution to the aqueous solution of intermediate Ⅰ, the first stage reaction temperature is controlled at 20-30 ℃, the reaction time is controlled at 30-60min, the second stage is heated to 60-80 ℃, the reaction time is controlled at 6-8h, after the reaction is completed, the reaction is rotary evaporated and vacuum dried to obtain intermediate Ⅱ; S30. Under N2 protection, add Cl-based Lewis acid metal salt to the molten intermediate II, control the reaction temperature at 60-90°C, and control the reaction time at 6-8h to obtain -Lewis bis-acidic bis-sulfonic acid metal-based ionic liquid catalyst.

4. The method for preparing the acidic ionic liquid catalyst according to claim 3, characterized in that: The molar ratio of triethylenediamine to sulfonic acid groups in step S10 is 1:

2.

5. The method for preparing the acidic ionic liquid catalyst according to claim 3, characterized in that: The molar ratio of the hydrochloric acid solution to the aqueous solution of intermediate I in step S20 is 2:

1.

6. The method for preparing the acidic ionic liquid catalyst according to claim 3, characterized in that: In step 30, the molar ratio of the Cl-based Lewis acidic metal salt to the intermediate II is 2:

1.

7. The method for preparing the acidic ionic liquid catalyst according to claim 3, characterized in that: Complex catalytic properties of triethylenediamine functionalized cationic groups containing disulfonic acid groups and Lewis acidic metal active site species.

8. The method for preparing the acidic ionic liquid catalyst according to claim 3, characterized in that: The sulfonic acid group is an alkylsulfonic acid.

9. The method for preparing the acidic ionic liquid catalyst according to claim 3, characterized in that: The solvent of the sulfonic acid group solution is one of ethyl acetate, propyl acetate, butyl acetate and n-propyl acetate.

10. An acidic ionic liquid catalyst, a preparation method and its application in degrading waste textiles.

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