Preparation method of lignin sulfonate and application thereof in high-temperature dyeing of polyester

Abstract

The application discloses a preparation method of lignin sulfonate and application of the lignin sulfonate in high-temperature dyeing of polyester, and belongs to the technical field of dye dispersants. The preparation method is as follows: SBA-15 after alkali etching is immersed in a precursor solution, and is subjected to aging, drying and calcination treatment; the obtained metal-loaded SBA-15 is immersed in a 3-mercaptopropyltrimethoxysilane toluene solution, and tetraethyl orthosilicate is added to perform a reaction, so as to obtain a silanization modification catalyst; the silanization modification catalyst is oxidized through a peroxymonosulfuric acid aqueous solution, so as to obtain a Mn-Cu@SO3H / SiO2 catalyst; lignin is added into deionized water, polyformaldehyde and the Mn-Cu@SO3H / SiO2 catalyst are added to perform a reaction, and sodium sulfite is added to perform a reaction, so as to obtain the lignin sulfonate. The prepared lignin sulfonate has excellent high-temperature dispersion stability, low fiber staining and high dispersing force characteristics, and can be applied to high-temperature dyeing of polyester fabrics.

Description

Technical Field

[0001] This invention relates to the field of dye dispersant technology, and more specifically, to a method for preparing lignin sulfonate and its application in high-temperature dyeing of polyester. Background Technology

[0002] Lignosulfonates, as natural polymeric dye dispersants, are widely used in fabric dyeing. However, existing methods for preparing ligninsulfonates still have many shortcomings:

[0003] (1) Poor dispersion stability: The dispersion performance of lignin sulfonates prepared by traditional methods is easily reduced under high temperature conditions (such as the dyeing temperature of polyester is usually 130℃-140℃), which leads to the aggregation of dye particles, affects the dyeing uniformity, and produces defects such as color spots and color patches.

[0004] (2) Insufficient heat resistance: Existing products are prone to decomposition or structural changes in high-temperature environments, leading to instability of the dispersion system and failure to effectively maintain the dispersion state of dye particles, thus affecting the dyeing effect.

[0005] (3) Fiber staining and reduction issues: Some lignin sulfonate products cause serious fiber staining and affect the color fastness of fabrics.

[0006] Therefore, there is an urgent need to develop a new method for preparing lignin sulfonate to improve its high-temperature dispersion stability, heat resistance, and low staining properties, so as to meet the high-performance requirements of dispersants for high-temperature dyeing of polyester. Summary of the Invention

[0007] The purpose of this invention is to overcome the shortcomings of the prior art and provide a method for preparing lignin sulfonate and its application in high-temperature dyeing of polyester.

[0008] To achieve the above objectives, the present invention adopts the following technical solution:

[0009] A method for preparing lignin sulfonate, comprising the following steps:

[0010] (a) The alkaline-etched mesoporous silica SBA-15 was impregnated in a precursor solution composed of manganese nitrate solution and copper nitrate solution. After impregnation, the product was aged, dried, and then calcined to obtain a metal-supported SBA-15 catalyst.

[0011] (b) The metal-supported SBA-15 was impregnated in a 3-mercaptopropyltrimethoxysilane toluene solution, and the crosslinking agent tetraethyl orthosilicate was added to carry out the reaction to obtain the silanized modified catalyst.

[0012] (c) The silanized modified catalyst was mixed with an aqueous solution of performic acid and stirred for oxidation to obtain the Mn-Cu@SO3H / SiO2 catalyst;

[0013] (d) Add lignin to deionized water, adjust the pH of the system to 10-11, add paraformaldehyde and Mn-Cu@SO3H / SiO2 catalyst to react, adjust the pH of the system to 3-4 after the reaction, add sodium sulfite to react, filter out Mn-Cu@SO3H / SiO2 catalyst after the reaction, filter the filtrate through ultrafiltration membrane, rotary evaporation and spray drying to obtain lignin sulfonate.

[0014] The present invention is further configured such that, in step (a), the precursor solution is a mixture of manganese nitrate solution and copper nitrate solution in a volume ratio of 1:1, and after alkaline etching, SBA-15 is impregnated with the precursor solution in a ratio of 1g:1mL.

[0015] The present invention is further configured such that, in step (a), the impregnation time is 4-6 h, the aging temperature is 55-65 °C, and the aging time is 18-24 h; the calcination temperature is 500-550 °C, and the calcination time is 3-5 h.

[0016] The present invention is further configured such that, in step (b), the concentration of the 3-mercaptopropyltrimethoxysilane toluene solution is 10 wt%, and the metal-supported SBA-15 catalyst is impregnated with the 10 wt% MPTMS toluene solution at a ratio of 1 g: 20 mL.

[0017] The present invention is further configured such that, in step (b), the amount of tetraethyl orthosilicate used is 40% of the mass of 3-mercaptopropyltrimethoxysilane.

[0018] The present invention is further configured such that, in step (b), the reaction temperature is 95-110℃ and the reaction time is 5-8h.

[0019] The present invention is further configured such that, in step (c), the concentration of performic acid aqueous solution is 5wt%, the mass-volume ratio of silanization modified catalyst to performic acid aqueous solution is 1:15, and the oxidation time is 2-3h.

[0020] The present invention is further configured such that, in step (d), lignin is obtained by using papermaking black liquor as raw material and then undergoing flocculation, filtration, acid precipitation, pressure filtration and drying.

[0021] The present invention is further configured such that, in step (d), the mass ratio of lignin to paraformaldehyde, Mn-Cu@SO3H / SiO2 catalyst and sodium sulfite is 30:(8-10):(1.5-3):(15-20).

[0022] Application of a lignin sulfonate prepared by the above method in high-temperature dyeing of polyester.

[0023] In summary, the present invention has the following beneficial effects:

[0024] This invention prepares lignin sulfonate using a novel catalyst, Mn-Cu@SO3H / SiO2. The resulting lignin sulfonate exhibits excellent high-temperature dispersion stability (heat resistance grade 4.5 at 155℃), low fiber staining (grade 4.5), and high dispersibility (99.1%). It can be effectively applied in the field of high-temperature dyeing of polyester fabrics, ensuring dyeing results (K / S value of dyed polyester fabrics is above 99%, and color fastness is ≥ grade 4). Detailed Implementation

[0025] The technical solution of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0026] The lignin sulfonate of this invention for high-temperature dyeing of polyester is prepared by the following method:

[0027] (a) Add mesoporous silica SBA-15 to 5wt% ammonia water (the ratio of SBA-15 to ammonia water is 1g:5-10mL), and place it in a constant temperature water bath at 55-60℃ for stirring and etching for 2-4 hours; immerse the alkaline-etched mesoporous silica SBA-15 in a precursor solution prepared by mixing manganese nitrate solution and copper nitrate solution at a volume ratio of 1:1 for 4-6 hours (after alkaline etching, SBA-15 is immersed in the precursor solution at a ratio of 1g:1mL), and age it at 55-65℃ for 18-24 hours after immersion. After drying the product, calcine the product (calcine temperature is 500-550℃, calcine time is 3-5 hours) to obtain the metal-supported SBA-15 catalyst.

[0028] (b) Impregnate metal-supported SBA-15 in a 10 wt% 3-mercaptopropyltrimethoxysilane toluene solution (the metal-supported SBA-15 catalyst is impregnated with a 10 wt% MPTMS toluene solution at a ratio of 1 g: 20 mL), add crosslinking agent tetraethyl orthosilicate (40% of the mass of 3-mercaptopropyltrimethoxysilane), and react at 95-110 °C for 5-8 h to obtain a silanized modified catalyst;

[0029] (c) The silanized modified catalyst was mixed with 5 wt% performic acid aqueous solution and stirred for 3-4 h (the mass-volume ratio of the silanized modified catalyst to the performic acid aqueous solution was 1:15) to prepare the Mn-Cu@SO3H / SiO2 catalyst.

[0030] (d) Flocculant was added to the black liquor of papermaking for flocculation. After filtration, dilute sulfuric acid was added to the filtrate until the pH of the system reached 2-3. Acid precipitation was carried out at 50-60℃. The mixture was then pressure filtered to separate the filter cake, which was washed several times with water, vacuum dried to constant weight, and pulverized to obtain high-purity lignin. The lignin was added to deionized water, and the pH of the system was adjusted to 10-11. Paraformaldehyde and Mn-Cu@SO3H / SiO2 catalyst were added to react. After the reaction, the pH of the system was adjusted to 3-4, and sodium sulfite was added to react. After the reaction, the Mn-Cu@SO3H / SiO2 catalyst was filtered out. The filtrate was filtered through an ultrafiltration membrane, rotary evaporated, and spray dried to obtain lignin sulfonate. The mass ratio of lignin to paraformaldehyde, Mn-Cu@SO3H / SiO2 catalyst, and sodium sulfite was 30:(8-10):(1.5-3):(15-20).

[0031] Example 1

[0032] (1) Add mesoporous silica SBA-15 to 5wt% ammonia water (the ratio of SBA-15 to ammonia water is 1g:5mL), and place it in a constant temperature water bath at 60℃ for 3 hours of stirring and etching. After etching, wash with deionized water until neutral, and dry at 80℃ to constant weight. Mix 0.1mol / L manganese nitrate solution and 0.1mol / L copper nitrate solution at a volume ratio of 1:1 to obtain a precursor solution. Add SBA-15 to the precursor solution at a ratio of 1g:1mL after etching and impregnate for 4 hours. After impregnation, age at 60℃ for 24 hours. Then, place the product in an oven at 80℃ for 12 hours and calcine in a muffle furnace at 550℃ for 3 hours to obtain a metal-supported SBA-15 catalyst. The metal-supported SBA-15 catalyst was impregnated in a 10 wt% 3-mercaptopropyltrimethoxysilane (MPTMS) toluene solution at a ratio of 1 g:20 mL. Tetraethyl orthosilicate (TEOS) as a crosslinking agent (40% of the mass of MPTMS) was added, and the mixture was refluxed at 100 °C for 6 hours. After the reaction, the solid product was collected by filtration and washed three times with anhydrous ethanol to obtain the silanized modified catalyst. The silanized modified catalyst and the 5 wt% performic acid aqueous solution were mixed at a mass-to-volume ratio of 1:15. The mixture was stirred at room temperature (25 °C) for 4 hours. After oxidation, the solid product was collected by filtration, washed with water until neutral, and then dried to obtain the Mn-Cu@SO3H / SiO2 catalyst.

[0033] (2) Polyacrylamide was added to the black liquor of papermaking (initial pH=12) for flocculation. After filtration, 10wt% dilute sulfuric acid was added to the filtrate until the pH value of the system reached 2.8. The mixture was acidified at 60℃ for 3h. Then the mixture was transferred to a plate and frame filter press for filtration. The filter cake was separated, washed with water 3 times, and dried in a vacuum drying oven at 60℃ and vacuum degree -0.09MPa until constant weight (moisture content <5%). After pulverization, high-purity lignin was obtained.

[0034] (3) The lignin obtained in step (2) was added to deionized water (the mass ratio of lignin to deionized water was 1:1.5). After stirring and mixing, the pH of the system was adjusted to 10.5 with sodium hydroxide solution. Paraformaldehyde and Mn-Cu@SO3H / SiO2 catalyst were added, and the reaction was stirred at 80°C for 2 hours. Then, 10wt% dilute sulfuric acid was added to adjust the pH of the system to 3.5, and sodium sulfite was added. The reaction was stirred at 105°C for 5 hours. The mass ratio of lignin to paraformaldehyde, Mn-Cu@SO3H / SiO2 catalyst and sodium sulfite was 30:9:2:18.

[0035] (4) After the reaction is completed, the Mn-Cu@SO3H / SiO2 catalyst is recovered by filtration. The filtrate is filtered with a 10000Da ultrafiltration membrane. Then the retentate is rotary evaporated at 60℃ and vacuum degree -0.095MPa until the solid content is 30%. Then it is spray dried (inlet air 180℃, outlet air 85℃) to obtain sodium lignosulfonate powder.

[0036] Comparative Example 1

[0037] Sodium lignosulfonate was prepared according to the method of Example 1, except that the metal-supported SBA-15 catalyst of step (1) was used to replace the Mn-Cu@SO3H / SiO2 catalyst in step (3) for the hydroxymethylation and sulfonation reactions.

[0038] Comparative Example 2

[0039] Sodium lignosulfonate was prepared according to the method of Example 1, except that the hydroxymethylation and sulfonation reactions in step (3) were carried out by replacing the Mn-Cu@SO3H / SiO2 catalyst with the same mass of the silanization modified catalyst in step (1).

[0040] The performance of sodium lignosulfonate prepared in Example 1, Comparative Example 1, and Comparative Example 2 was tested respectively, and the results are shown in the table below (sulfate content, heat resistance, staining, and dispersing power were tested according to the industry standard "HGT-3507-2008-Sodium Lignosulfonate Dispersant"):

[0041]

[0042] Application examples

[0043] Sodium lignin sulfonate prepared in Example 1 and Comparative Examples 1-2 were applied to high-temperature dyeing of polyester, and the resulting dyed fabrics were denoted as Fabric A-Fabric C, respectively. The dyeing method was as follows: Sodium lignin sulfonate was added to an acetate-sodium acetate buffer solution (pH = 4.5), and disperse dye Atlon Yellow Brown SW was added and stirred until homogeneous to obtain a dye bath (the mass ratio of sodium lignin sulfonate to acetate-sodium acetate buffer solution and Atlon Yellow Brown SW was 0.03:100:0.5); 30g of polyester taffeta scouring fabric (30d / g, 50g / m²) was used. 2 The fabric was immersed in a dye bath (liquor ratio of 1:3.3), and the temperature was increased from 60℃ to 135℃ at a rate of 2℃ / min. This temperature was maintained for 40 minutes, then the temperature was lowered to 80℃. The fabric was then removed, washed three times, and subsequently dehydrated and dried to obtain the dyed fabric. The fabric performance test results are shown in the table below.

[0044]

[0045] According to GB / T 6529-2008 "Standard Atmospheres for Conditioning and Testing of Textiles", the fabric was conditioned for 24 hours, and then tested at multiple points using an UltraScanXE computer colorimeter under a 20mm aperture, D65 light source, and 10° viewing angle. The color difference ΔE was calculated. Color fastness to rubbing was tested according to GB / T 3920-2024, color fastness to washing with soap according to GB / T 3921-2008, and color fastness to perspiration according to GB / T 3922-2013.

[0046] The above description is merely a preferred embodiment of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions falling within the scope of the present invention's concept are within the scope of protection of the present invention. It should be noted that for those skilled in the art, any improvements and modifications made without departing from the principles of the present invention should also be considered within the scope of protection of the present invention.

Claims

1. A method for preparing lignin sulfonate, characterized in that, Includes the following steps (a) The alkaline-etched mesoporous silica SBA-15 was impregnated in a precursor solution composed of manganese nitrate solution and copper nitrate solution. After impregnation, the product was aged, dried, and then calcined to obtain a metal-supported SBA-15 catalyst. (b) The metal-supported SBA-15 was impregnated in a 3-mercaptopropyltrimethoxysilane toluene solution, and the crosslinking agent tetraethyl orthosilicate was added to carry out the reaction to obtain the silanized modified catalyst. (c) The silanized modified catalyst was mixed with an aqueous solution of performic acid and stirred for oxidation to obtain the Mn-Cu@SO3H / SiO2 catalyst; (d) Add lignin to deionized water, adjust the pH of the system to 10-11, add paraformaldehyde and Mn-Cu@SO3H / SiO2 catalyst to react, adjust the pH of the system to 3-4 after the reaction, add sodium sulfite to react, filter out Mn-Cu@SO3H / SiO2 catalyst after the reaction, filter the filtrate through ultrafiltration membrane, rotary evaporation and spray drying to obtain lignin sulfonate.

2. The method for preparing a lignin sulfonate according to claim 1, characterized in that, In step (a), the precursor solution is prepared by mixing manganese nitrate solution and copper nitrate solution in a volume ratio of 1:

1. After alkaline etching, SBA-15 is impregnated with the precursor solution in a ratio of 1g:1mL.

3. The method for preparing a lignin sulfonate according to claim 1, characterized in that, In step (a), the soaking time is 4-6 hours, the aging temperature is 55-65℃, and the aging time is 18-24 hours; the roasting temperature is 500-550℃, and the roasting time is 3-5 hours.

4. The method for preparing a lignin sulfonate according to claim 1, characterized in that, In step (b), the concentration of 3-mercaptopropyltrimethoxysilane toluene solution is 10 wt%, and the metal-supported SBA-15 catalyst is impregnated with 10 wt% MPTMS toluene solution at a ratio of 1 g: 20 mL.

5. The method for preparing a lignin sulfonate according to claim 1, characterized in that, In step (b), the amount of tetraethyl orthosilicate used is 40% of the mass of 3-mercaptopropyltrimethoxysilane.

6. The method for preparing a lignin sulfonate according to claim 1, characterized in that, In step (b), the reaction temperature is 95-110℃ and the reaction time is 5-8h.

7. The method for preparing a lignin sulfonate according to claim 1, characterized in that, In step (c), the concentration of performic acid aqueous solution is 5wt%, the mass-volume ratio of silanization modified catalyst to performic acid aqueous solution is 1:15, and the oxidation time is 2-3h.

8. The method for preparing a lignin sulfonate according to claim 1, characterized in that, In step (d), lignin is obtained by using black liquor from papermaking as raw material, and then undergoing flocculation, filtration, acid precipitation, pressure filtration and drying.

9. The method for preparing a lignin sulfonate according to claim 1, characterized in that, In step (d), the mass ratio of lignin to paraformaldehyde, Mn-Cu@SO3H / SiO2 catalyst, and sodium sulfite is 30:(8-10):(1.5-3):(15-20).

10. The application of a lignin sulfonate prepared by any one of claims 1-9 in high-temperature dyeing of polyester.

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