An active blue dye and a process for its preparation

Abstract

The application provides an active blue dye, which is compounded by 50-55 parts by weight of a dye shown in formula (1) and 45-50 parts by weight of a dye shown in formula (2); the two dyes of the same isomer are compounded, the solubility and stability of the dye in an alkaline medium are improved, and thus the application performance of the dye is increased.

Description

Technical Field

[0001] This invention belongs to the field of reactive dye synthesis technology, specifically relating to a reactive blue dye and its preparation method. Background Technology

[0002] Reactive dyes have many advantages such as a wide variety, complete color spectrum, bright color, good leveling properties, and low price, and are widely used by printing and dyeing factories. Among reactive blue products, Blue B-2GLN (CI Reactive Blue 194) is a relatively important blue variety. It is a heterogeneous double reactive dye. As one of the three primary colors of dye, it is mainly used for dyeing cotton, linen, silk and viscose fibers. However, at present, this dye is not green enough, has a long production cycle, low solubility and solid content, and is produced by salting out process, which results in large amount of pollution, low yield and high energy consumption, and cannot meet the requirements of green environmental protection. Specifically, it is manifested in the following ways: (1) The solubility in cold water in neutral medium is only 80g / l. After adding alkali, the solubility drops rapidly to 50g / l. The storage stability is not good. (1) Poor solubility and poor uniformity. When dyeing at high concentrations, it is easy to precipitate after adding alkali, resulting in color spots, etc.; and the solubility is also small due to the lack of water-soluble groups in the molecule. After adding alkali, the sulfate ester group falls off, further reducing the water-soluble groups, making the dye easy to precipitate and resulting in poor fastness performance; (2) The acid-tanning time during dye synthesis is long and difficult to control, which easily produces red secondary dyes, resulting in a reddish and dark color. The diazo compound is very viscous, so the reaction volume must be increased to increase the fluidity of the reaction system. If the volume is too large, the cooling energy consumption is high, the solid content of the material is extremely low, and the energy consumption is high; (3) Multiple diazo reactions increase the safety risk factor, the salting-out production process has a large amount of sewage discharge and low yield. Summary of the Invention

[0003] The purpose of this invention is to provide a reactive blue dye that can at least solve some of the defects existing in the prior art.

[0004] To achieve the above objectives, the present invention adopts the following technical solution:

[0005] A reactive blue dye is prepared by compounding 50-55 parts by weight of the dye shown in formula (1) and 45-50 parts by weight of the dye shown in formula (2);

[0006]

[0007] Furthermore, the aforementioned reactive blue dye is a compound of 53 parts by weight of the dye shown in formula (1) and 47 parts by weight of the dye shown in formula (2).

[0008] In addition, the present invention also provides a method for preparing a reactive blue dye, comprising the following steps:

[0009] S1. A mixed solution A, prepared by dissolving p-aminobenzenesulfonic acid and hydrochloric acid in water, is reacted with sodium nitrite solution B in a microchannel reactor according to the designed dosage ratio to obtain feed solution C.

[0010] S2. The mixed solution D of H acid and sodium bicarbonate is reacted with the feed solution C in the microchannel reactor II according to the designed dosage ratio to obtain feed solution E.

[0011] S3. The mixture of para-ester and meta-ester is condensed with cyanuric chloride at low temperature to obtain a primary condensate.

[0012] S4. Add the intermediate solution to the primary condensate obtained in step S3 to carry out a secondary condensation reaction to obtain the secondary condensate.

[0013] S5. The mixture F of secondary condensate, hydrochloric acid and accelerator Retan is reacted with sodium nitrite solution B in microchannel reactor three according to the designed dosage ratio to obtain feed solution G.

[0014] S6. Add sodium bicarbonate to solution E and react it with solution G in microchannel reactor four according to the designed dosage ratio. Dry the reaction product to obtain the reactive blue dye.

[0015] Specifically, in step S1, the concentration of mixed solution A is 10-12%, the mass ratio of p-aminobenzenesulfonic acid to hydrochloric acid is 1:(1-1.02), and the concentration of sodium nitrite solution B is 30-35%. The flow rate ratio of mixed solution A to sodium nitrite solution B, injected into the microchannel reactor by a syringe pump, is 15:1, the reaction temperature is 12-15℃, and the reaction time is 10-12 min.

[0016] Specifically, in step S2, the H acid solution is an aqueous solution with pH = 6-6.3 and mass concentration of 10-12% prepared by dissolving H acid; the mass ratio of H acid solution to sodium bicarbonate is 1:(2.0-2.5); the flow rate ratio of mixed solution D to feed solution C pushed into the microchannel reactor II by the injection pump is 1:3, the reaction temperature is 5-10℃, and the reaction time is 12-15min.

[0017] Specifically, in step S3, the mass ratio of para-ester to meta-ester is (50-55):(45-50), and the mass ratio of the mixture of para-ester and meta-ester to cyanuric chloride is 1:(1-1.01); the pH of the primary condensation reaction is 3-3.2, the reaction temperature is 0-5℃, and the reaction time is 3-3.5h.

[0018] Specifically, in step S4, the mass ratio of the meta-ester solution to the mixture of para-ester and meta-ester is 1:1, the pH of the secondary condensation reaction is 4-5, the reaction temperature is 30-32℃, and the reaction time is 4-5h.

[0019] Specifically, in step S5, the amount of Retan added is 1-1.5% of the mass of the secondary condensate; the flow rate ratio of the mixture F and the sodium nitrite solution B pushed into the microchannel reactor three by the injection pump is 25:1, the reaction temperature is 15-18℃, and the reaction time is 12-15min.

[0020] Specifically, in step S6, the ratio of the flow rate of the sodium bicarbonate-added solution E to the solution G, which is pushed into the microchannel reactor four by the injection pump, is 1:0.8, the reaction temperature is 10-12℃, and the reaction time is 10 min.

[0021] Specifically, in step S6, the pH value of the material at the four outlets of the microchannel reactor is 6 to 6.5.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] (1) The reactive blue dye provided by the present invention is made by compounding two dyes with two isomers to improve the solubility of the dye and its stability in alkaline media, thereby increasing the application performance of the dye.

[0024] (2) The reactive blue dye provided by this invention uses a microchannel reactor for the reaction process. Taking advantage of its strong heat and mass transfer capabilities and good mixing uniformity, the reaction time is greatly shortened. The diazo and coupling reaction time is shortened from the original 2-4 hours to less than 15 minutes. Moreover, it can form continuous production, greatly shortening the production cycle, changing the intermittent production mode of fine chemicals, and is suitable for industrial production.

[0025] (3) The reactive blue dye provided by this invention adds Retan as an accelerator during the preparation process to increase the material flowability, resulting in high mass transfer efficiency and instantaneous uniform mixing of materials, which can achieve the best reaction effect and the product purity can reach more than 90%.

[0026] (4) The reactive blue dye provided by this invention can achieve zero discharge of wastewater by precisely controlling the reaction temperature, time and material ratio during the preparation process, so that the product does not need to be salted out and the yield is increased to 93%. The dye produced has good color and application performance.

[0027] The present invention will now be described in further detail with reference to the accompanying drawings. Attached Figure Description

[0028] Figure 1 This is a schematic diagram of the apparatus for preparing reactive blue dye in this invention;

[0029] Figure 2This is a comparison chart of the HPLC detection results of the reactive blue dye prepared by the present invention and the existing reactive blue 194, wherein (a) is the reactive blue dye of the present invention and (b) is reactive blue 194. Detailed Implementation

[0030] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. 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 skilled in the art without creative effort are within the scope of protection of the present invention.

[0031] The present invention provides an active blue dye, which is compounded from 50-55 parts by weight of the dye shown in formula (1) and 45-50 parts by weight of the dye shown in formula (2); preferably, the dye of formula (1) is 53 parts by weight and the dye of formula (2) is 47 parts by weight.

[0032]

[0033]

[0034] like Figure 1 As shown, the preparation process of the above-mentioned reactive blue dye is as follows:

[0035] S1. A mixed solution A, prepared by dissolving p-aminobenzenesulfonic acid and hydrochloric acid in water, is reacted with sodium nitrite solution B in microchannel reactor-1 according to the designed dosage ratio to obtain feed solution C; the reaction formula is as follows:

[0036]

[0037] Specifically, the concentration of mixed solution A is 10-12%, the mass ratio of p-aminobenzenesulfonic acid to hydrochloric acid is 1:(1-1.02), and the concentration of sodium nitrite solution B is 30-35%. Mixed solution A and sodium nitrite solution B are injected into microchannel reactor 1 by an injection pump for reaction at a flow rate ratio of 15:1, a reaction temperature of 12-15℃, and a reaction time of 10-12 min.

[0038] S2. The mixed solution D of H acid and sodium bicarbonate is reacted with feed solution C in microchannel reactor 2 according to the designed dosage ratio to obtain feed solution E; the reaction formula is as follows:

[0039]

[0040] Specifically, the H acid solution is an aqueous solution with pH = 6-6.3 and mass concentration of 10-12% prepared by dissolving H acid (i.e., 1-amino-8-naphthol-3,6-disulfonic acid); the mass ratio of H acid solution to sodium bicarbonate is 1:(2.0-2.5); the mixed solution D and the feed solution C obtained in step S1 above are pushed into the microchannel reactor 2 by an injection pump to react, with a flow rate ratio of 1:3, a reaction temperature of 5-10℃, and a reaction time of 12-15 min.

[0041] S3. A mixture of para-ester and meta-ester is subjected to a primary condensation with cyanuric chloride at low temperature to obtain a primary condensate; the reaction formula is as follows:

[0042]

[0043] Specifically, the mass ratio of para-ester to meta-ester is (50-55):(45-50), preferably 53:47, and the mass ratio of the mixture of para-ester and meta-ester to cyanuric chloride is 1:(1-1.01); the pH of the primary condensation reaction is 3-3.2, the reaction temperature is 0-5℃, and the reaction time is 3-3.5h.

[0044] S4. Add a meta-bisolution (i.e., 2,4-diaminobenzenesulfonic acid) to the primary condensate obtained in step S3 to carry out a secondary condensation reaction, thereby obtaining a secondary condensate; the reaction formula is as follows:

[0045]

[0046] Specifically, the mass ratio of the meta-ester solution to the mixture of para-ester and meta-ester is 1:1, the pH of the secondary condensation reaction is 4-5, the reaction temperature is 30-32℃, and the reaction time is 4-5h.

[0047] S5. The mixture F of the secondary condensate, hydrochloric acid, and accelerator Retan is reacted with sodium nitrite solution B at the designed dosage ratio in microchannel reactor 3 to obtain feed solution G; the reaction formula is as follows:

[0048]

[0049] Specifically, the accelerator Retan was purchased from Jiangyin Jiuniu Technology Co., Ltd. as accelerator Retan-37. Its technical specifications are shown in Table 1. The amount added is 1-1.5% of the mass of the secondary condensate. The mixture F and sodium nitrite solution B are injected into the microchannel reactor 3 by an injection pump. The flow rate ratio is 25:1, the reaction temperature is 15-18℃, and the reaction time is 12-15 min.

[0050] Table 1: Technical Specifications of Accelerator Retan

[0051] Indicator Name index Appearance White to beige powder pH value (1% aqueous solution) 6-10 Solid content 91-97％

[0052] S6. Add sodium bicarbonate to feed solution E and react it with feed solution G in microchannel reactor 4 according to the designed dosage ratio. Dry the reaction product to obtain product H (i.e., reactive blue dye); the reaction formula is as follows:

[0053]

[0054] Specifically, the mass ratio of sodium bicarbonate to H acid is 1:(8.0-10). The feed solution E with added sodium bicarbonate and feed solution G are pushed into microchannel reactor 4 by an injection pump for reaction, with a flow rate ratio of 1:0.8, a reaction temperature of 10-12℃, and a reaction time of 10 min. After the reaction is completed, the pH value of the material at the outlet of microchannel reactor 4 is 6-6.5. No salting out is required after the reaction is completed, and the product H is obtained by direct spray drying.

[0055] The performance and effects of the reactive blue dye of the present invention are illustrated below through specific embodiments.

[0056] Example 1:

[0057] This embodiment provides a reactive blue dye, which is compounded from 53 parts of the dye shown in formula (1) and 47 parts of the dye shown in formula (2);

[0058]

[0059] The preparation process of the above-mentioned reactive blue dye is as follows:

[0060] (1) Dissolve 1 part of p-aminobenzenesulfonic acid and 1.01 part of hydrochloric acid in water to prepare a 10% mixed solution, which is called mixed solution A; take 1.02 parts of sodium nitrite and dissolve it in water to form a 30% sodium nitrite solution B. The mixed solution A and sodium nitrite solution B are metered according to the volume ratio and pushed into the microchannel reactor-1 (a polytetrafluoroethylene tube with an inner diameter D = 0.8 mm and a length L = 1.5 m) by an injection pump at a flow rate ratio of 15:1. The heat exchanger circuit of the microchannel reactor-1 is connected to the constant temperature jacket. Adjust the reaction temperature to about 15°C. The residence time of the mixed solution A and sodium nitrite solution B in the microchannel reactor-1 is 10 min. Collect the outlet material of the microchannel reactor-1 and destroy the excess sodium nitrite with aminosulfonic acid to obtain the feed solution C.

[0061] (2) Dissolve 0.96 parts of H acid to prepare a 10% aqueous solution with pH=6. Then add 1.92 parts of sodium bicarbonate to the H acid solution and stir evenly to obtain mixed solution D. The feed solution C and mixed solution D are pushed into microchannel reactor 2 (a polytetrafluoroethylene tube with inner diameter D=0.5mm and length L=2m) by calibrated feed injection pumps at a volume ratio of 3:1. The residence time of feed solution C and mixed solution D in microchannel reactor 2 is 15min. Collect the outlet material of microchannel reactor 2. The pH value is 2.0-2.2 to obtain feed solution E.

[0062] (3) 0.53 parts of para ester and 0.47 parts of meta ester were condensed with 1.01 parts of cyanuric chloride at low temperature. The first condensation was completed at 0-5℃ and pH=3 for 3 hours to obtain a first condensate.

[0063] (4) Add 1 part of the intermediate solution to the primary condensate, adjust the temperature to 30-32℃, and the pH of the medium to 4-5. React for 4 hours under these conditions until the endpoint is reached to obtain the secondary condensate.

[0064] (5) Add the promoter Retan (1% of the total amount of condensate) to the secondary condensate obtained above, and then add 2.2 parts of hydrochloric acid and mix well to form mixture F. Take 1.02 parts of sodium nitrite and dissolve it in water to form a sodium nitrite solution B with a mass concentration of 30%. The mixture F and sodium nitrite solution B are respectively pumped into the microchannel reactor 3 (a polytetrafluoroethylene tube with an inner diameter of D = 0.8 mm and a length of L = 1.5 m) by a syringe pump according to the calibrated feed ratio. The flow rate ratio is 25:1 and the residence time is 15 min. The heat exchanger circuit of the microchannel reactor 3 is connected to the constant temperature jacket. Adjust the reaction temperature to about 18°C. Collect the outlet material of the microchannel reactor 3 and use aminosulfonic acid to remove excess sodium nitrite to obtain feed solution G.

[0065] (6) After adjusting the pH of the prepared solution E to 6.5-6.8, add sodium bicarbonate in a mass fraction ratio of 1:8.0 with H acid, stir evenly, and push the calibrated solution E and solution G into the microchannel reactor 4 (a polytetrafluoroethylene tube with an inner diameter D = 0.5 mm and a length L = 2 m) by injection pump according to the volume ratio. The flow rate ratio is 1:0.8, and the residence time of solution E and solution G in the microchannel reactor 4 is 10 min. Collect the outlet material of the microchannel reactor 4. The pH value is 6.0-6.5. After the reaction is completed, there is no need for salting out. Directly spray dry to obtain product H.

[0066] The physical properties of the reactive blue dye (i.e., product H) prepared in this embodiment were compared with those of the existing Reactive Blue 194. The test results are shown in Table 1. The high-performance liquid chromatography (HPLC) test results of the two are as follows: Figure 2As shown.

[0067] Table 1:

[0068]

[0069] Table 2 shows a comparison of the dyeing results of the reactive blue dye (i.e., product H) prepared in this embodiment with those of the existing reactive blue 194.

[0070] Table 2:

[0071]

[0072] Example 2:

[0073] This embodiment investigated the performance effect of isomer-blended dyes versus single dyes. The performance of product H prepared in Example 1 (i.e., the dye blended from formulas (1) and (2)) was compared with that of single dyes of formula (1) and single dyes of formula (2), and the results are shown in Table 3.

[0074] Table 3:

[0075]

[0076] Example 3:

[0077] This embodiment investigated the effect of the accelerator Retan on product performance and preparation process. Two groups, A and B, were used for the experiment. The reactive blue dye was prepared by the preparation process in Example 1 above. The preparation process of the experimental group B was roughly the same as that of the experimental group A, except that the accelerator Retan was not added during the preparation of the solution G. The test results of the products obtained by the experimental groups A and B are shown in Table 4.

[0078] Table 4:

[0079]

[0080]

[0081] The above examples are merely illustrative of the present invention and do not constitute a limitation on the scope of protection of the present invention. All designs that are the same as or similar to the present invention are within the scope of protection of the present invention.

Claims

1. A reactive blue dye, characterized in that: It is a compound of dyes shown in formula (1) in 50-55 parts by weight and dyes shown in formula (2) in 45-50 parts by weight; (1)； (2)。 2. The reactive blue dye as described in claim 1, characterized in that: It is a compound of dyes shown in formula (1) in 53 parts by weight and dyes shown in formula (2) in 47 parts by weight.

3. The method for preparing the reactive blue dye as described in claim 1 or 2, characterized in that, Includes the following steps: S1. A mixed solution A, prepared by dissolving p-aminobenzenesulfonic acid and hydrochloric acid in water, is reacted with sodium nitrite solution B in a microchannel reactor according to the designed dosage ratio to obtain feed solution C. S2. The mixed solution D of H acid and sodium bicarbonate is reacted with the feed solution C in the microchannel reactor II according to the designed dosage ratio to obtain feed solution E. S3. The mixture of para-ester and meta-ester is condensed with cyanuric chloride at low temperature to obtain a primary condensate. S4. Add the intermediate solution to the primary condensate obtained in step S3 to carry out a secondary condensation reaction to obtain the secondary condensate. S5. The mixture F of the secondary condensate, hydrochloric acid and accelerator Retan is reacted with sodium nitrite solution B in microchannel reactor three according to the designed dosage ratio to obtain feed solution G; the accelerator Retan is purchased from Jiangyin Jiuniu Technology Co., Ltd. as accelerator Retan-37. S6. Add sodium bicarbonate to solution E and react it with solution G in microchannel reactor four according to the designed dosage ratio. Dry the reaction product to obtain the reactive blue dye.

4. The preparation method according to claim 3, characterized in that, In step S1, the concentration of mixed solution A is 10-12%, the mass ratio of p-aminobenzenesulfonic acid to hydrochloric acid is 1:(1-1.02), and the concentration of sodium nitrite solution B is 30-35%. The flow rate ratio of mixed solution A to sodium nitrite solution B, which is pushed into the microchannel reactor by the injection pump, is 15:

1. The reaction temperature is 12-15℃, and the reaction time is 10-12 min.

5. The preparation method according to claim 3, characterized in that, In step S2, the H acid solution is an aqueous solution with pH=6-6.3 and mass concentration of 10-12% prepared by dissolving H acid; the mass ratio of H acid solution to sodium bicarbonate is 1:(2.0-2.5); the flow rate ratio of mixed solution D to feed solution C pushed into microchannel reactor II by injection pump is 1:3, the reaction temperature is 5-10℃, and the reaction time is 12-15min.

6. The preparation method according to claim 3, characterized in that, In step S3, the mass ratio of para-ester to meta-ester is (50-55):(45-50), and the mass ratio of the mixture of para-ester and meta-ester to cyanuric chloride is 1:(1-1.01); the pH of the primary condensation reaction is 3-3.2, the reaction temperature is 0-5℃, and the reaction time is 3-3.5h.

7. The preparation method according to claim 3, characterized in that, In step S4, the mass ratio of the meta-ester solution to the mixture of para-ester and meta-ester is 1:1, the pH of the secondary condensation reaction is 4-5, the reaction temperature is 30-32℃, and the reaction time is 4-5h.

8. The preparation method according to claim 3, characterized in that, In step S5, the amount of Retan accelerator added is 1-1.5% of the mass of the secondary condensate; the flow rate ratio of mixture F and sodium nitrite solution B to the reaction in the microchannel reactor is 25:1, the reaction temperature is 15-18℃, and the reaction time is 12-15 min.

9. The preparation method according to claim 3, characterized in that, In step S6, the ratio of the flow rate of the sodium bicarbonate-added solution E to the solution G is 1:0.8, the reaction temperature is 10-12℃, and the reaction time is 10 min.

10. The preparation method according to claim 9, characterized in that, In step S6, the pH value of the material at the four outlets of the microchannel reactor is 6 to 6.5.

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