Clean production process of sulfur black dye

Abstract

The invention discloses a clean production process of a sulfur black dye, which comprises the following steps: S1, uniformly mixing dinitrochlorobenzene and a sodium hydroxide aqueous solution, and carrying out hydrolysis reaction to obtain a sodium dinitrophenolate solution; s2, uniformly mixing part of the sodium dinitrophenolate solution with a catalyst and a solvent, and carrying out hydrogenation reaction by using hydrogen to obtain a sodium diaminophenol solution; and S3, taking the sodium diaminophenol solution, the residual sodium dinitrophenol solution and the sodium polysulfide solution, and carrying out condensation reaction to obtain the sulfur black dye. According to the production process, hydrogenation reduction clean production is adopted, the generation amount of three wastes can be greatly reduced, especially the amount of salt-containing wastewater can be reduced by 20-90%, the content of pollutants in residual liquid is low, treatment is easy, environmental pollution is reduced, the production period is short, the efficiency is high, the product quality is stable, the process control is simple and convenient, and the color fastness of the obtained sulfur black dye is higher.

Description

Technical Field

[0001] The invention relates to the technical field of sulfur black production, in particular to a clean production process of sulfur black dye. Background Art

[0002] Sulfur black, also known as sulfur element or sulfur blue, is a high molecular compound containing more sulfur. Its structure contains disulfide bonds and polysulfide bonds. These bonds may be unstable under certain conditions, resulting in changes in dye properties. It is mainly used for dyeing cotton textiles. Due to the different specifications of product color and performance, there are many varieties of sulphur black, such as sulphur black BN (cyan), sulphur black BRN and B2RN (cyan-red), sulphur black RN (red), sulphur black 2BR, water-soluble sulphur black, etc.

[0003] At present, the preparation process of sulphur black is generally: dinitrochlorobenzene is hydrolyzed into sodium dinitrophenolate, and then sulphurized with sodium polysulfide solution. However, this process has many reaction by-products, high output of three wastes, especially large amount of salt-containing wastewater, high treatment cost, and difficult to achieve clean production; and low production efficiency, high energy consumption, energy cannot be reasonably utilized, large-scale production lacks competitiveness, and the dyeing fastness of sulphur black produced by the existing process is not high, which needs to be improved. Summary of the invention

[0004] Based on the technical problems existing in the background technology, the present invention proposes a clean production process for sulphur black dye. The production process of the present invention adopts hydrogenation reduction clean production, which can greatly reduce the amount of three wastes generated, especially the amount of salt-containing wastewater can be reduced by 20-90%, the pollutant content in the residual liquid is low, it is easy to handle, and environmental pollution is reduced. The production cycle is short, the efficiency is high, the product quality is stable, the process control is simple, and the obtained sulphur black dye has higher color fastness.

[0005] The present invention provides a clean production process for sulfur black dye, comprising the following steps:

[0006] S1, taking dinitrochlorobenzene and sodium hydroxide aqueous solution and mixing them, and performing hydrolysis reaction to obtain sodium dinitrophenolate solution;

[0007] S2, taking part of the sodium dinitrophenolate solution, mixing it with a catalyst and a solvent, and performing a hydrogenation reaction with hydrogen to obtain a sodium diaminophenolate solution;

[0008] S3, taking the sodium diaminophenolate solution, the remaining sodium dinitrophenolate solution and the sodium polysulfide solution, and carrying out a condensation reaction to obtain sulphur black dye.

[0009] The reaction formula in S1 above is as follows:

[0010]

[0011] The reaction formula in S2 above is as follows:

[0012]

[0013] The reaction formula in S3 above is as follows:

[0014]

[0015]

[0016] The clean production process of the above-mentioned sulphur black dye can be carried out in a reaction system. The reaction system comprises: a hydrolysis reactor, a hydrogenation reactor, a filter, a sodium polysulfide preparation reactor, and a sulphurization reactor; wherein the first outlet of the hydrolysis reactor is connected to the inlet of the hydrogenation reactor, the second outlet of the hydrolysis reactor is connected to the inlet of the sulphurization reactor; the outlet of the hydrogenation reactor is connected to the inlet of the filter; the outlet of the filter and the outlet of the sodium polysulfide preparation reactor are connected to the inlet of the sulphurization reactor; and the sulphur black dye is obtained at the outlet of the sulphurization reactor.

[0017] The above reaction system can use metering pumps to transport raw materials, solutions, etc.; chemical pumps, flow meters, valves, etc. can be used for parameter control.

[0018] The above filter can filter and separate the catalyst for recycling.

[0019] In the above S2, the hydrogenation reaction can be carried out in a single reactor or in a multi-reactor series manner.

[0020] Due to the easy oxidation of raw materials and products, the entire reaction system must be thoroughly replaced with protective gas (such as nitrogen, etc.) in advance to ensure that there is no air residue in the reaction system before starting production.

[0021] Preferably, in S1, the molar ratio of dinitrochlorobenzene to sodium hydroxide is 1:2-5.

[0022] Preferably, in S1, the concentration of the sodium hydroxide aqueous solution is 100-300 g / L.

[0023] Preferably, in S1, the hydrolysis reaction temperature is 50-100°C, the time is 2-5h, and the pressure is normal pressure.

[0024] Preferably, in S1, the mass fraction of sodium dinitrophenolate in the sodium dinitrophenolate solution is 30-50wt%.

[0025] In the above S1, the weight ratio of dinitrochlorobenzene to the sodium hydroxide aqueous solution is 1:2-5.

[0026] Preferably, in S2, the catalyst is at least one of a metal catalyst, a metal oxide catalyst, a molecular sieve catalyst, and a nanocatalyst.

[0027] Preferably, in S2, the catalyst is at least one of a nickel-aluminum alloy catalyst, a nickel catalyst, a palladium-platinum catalyst, a copper-chromium catalyst, a rhodium catalyst, and a ruthenium catalyst.

[0028] Preferably, in S2, the solvent is one of benzene, methanol, ethanol, acetone, and sodium hydroxide aqueous solution.

[0029] Preferably, in S2, the solvent is an aqueous solution of sodium hydroxide having a concentration of 0.1-10 wt%.

[0030] Preferably, in S2, the hydrogenation reaction temperature is 50-120°C, the time is 5-12h, and the pressure is 1-3MPa.

[0031] Preferably, in S2, the weight ratio of the sodium dinitrophenolate solution to the catalyst is 1:0.005-0.05.

[0032] Preferably, in S2, the partial sodium dinitrophenolate solution accounts for 20-99 wt % of the total weight of the sodium dinitrophenolate solution.

[0033] Preferably, in S2, the mass fraction of sodium diaminophenolate in the sodium diaminophenolate solution is 10-40wt%.

[0034] Preferably, in S3, the sulfur index of sodium polysulfide is 2-5.

[0035] Preferably, in S3, the method for preparing the sodium polysulfide solution comprises the following steps: taking sulfur and a sodium hydrosulfide aqueous solution, reacting them to obtain a sodium polysulfide solution.

[0036] The reaction formula for preparing sodium polysulfide is as follows:

[0037] 2NaHS+S N-1 →Na2S n +H2S ↑ .

[0038] Preferably, the reaction temperature is 80-100° C., the reaction time is 4-8 h, and the reaction pressure is normal pressure.

[0039] Preferably, the concentration of the sodium hydrosulfide aqueous solution is 28-42 wt %.

[0040] Preferably, the weight ratio of sulfur to the sodium hydrosulfide aqueous solution is 1:2-4.

[0041] Preferably, in S3, the condensation reaction temperature is 50-150°C, the time is 5-10h, and the pressure is 0.05-0.5MPa.

[0042] Preferably, in S3, the weight ratio of the sodium diaminophenolate solution, the remaining sodium dinitrophenolate solution and the sodium polysulfide solution is 0.25-90:1:1-3.5.

[0043] The existing process generally uses sodium polysulfide and sodium dinitrophenol to carry out reduction reaction and condensation reaction to prepare sulphur black dye. This process produces a lot of sodium thiosulfate (commonly known as baking soda), resulting in the generation of a large amount of salt-containing wastewater, increasing environmental pollution, and the sulphur black dye prepared by this method has low color fastness;

[0044] The invention divides a sodium dinitrophenolate solution into two parts, conducts a hydrogenation reaction on one part of the sodium dinitrophenolate and hydrogen, and then reacts the two parts with the other part of the sodium dinitrophenolate and sodium polysulfide to obtain a sulfide black dye. This can significantly reduce the amount of salt-containing wastewater (i.e., a sodium bicarbonate aqueous solution), and greatly reduce the cost of wastewater treatment. In addition, hydrogen is a clean energy source, which can reduce pollution to the environment and reduce production and operation costs. In addition, the sulfide black dye prepared by this method has higher color fastness, and a variety of sulfide black dyes can be prepared. In addition, the reaction device system used in this process has a high degree of intensiveness, which effectively reduces device investment and enhances the competitiveness of large-scale operation of the sulfide black dye production process. DETAILED DESCRIPTION

[0045] The technical solution of the present invention is described in detail below through specific embodiments.

[0046] In the following Examples 1-3, a reaction system is used to produce sulphur black, and the reaction system includes: a hydrolysis reactor, a hydrogenation reactor, a filter, a sodium polysulfide preparation reactor, and a sulphurization reactor; wherein the first outlet of the hydrolysis reactor is connected to the inlet of the hydrogenation reactor, and the second outlet of the hydrolysis reactor is connected to the inlet of the sulphurization reactor; the outlet of the hydrogenation reactor is connected to the inlet of the filter; the outlet of the filter and the outlet of the sodium polysulfide preparation reactor are connected to the inlet of the sulphurization reactor; and sulphur black dye is obtained at the outlet of the sulphurization reactor.

[0047] Example 1

[0048] A clean production process for sulfur black dye comprises the following steps:

[0049] S1. The air in the entire reaction system is replaced with nitrogen, and then a metering pump is used to put molten dinitrochlorobenzene and a sodium hydroxide aqueous solution with a concentration of 150 g / L into a hydrolysis reactor, so that the molar ratio of dinitrochlorobenzene to sodium hydroxide is 1:3, and then the temperature in the reactor is adjusted to 95° C. and the pressure is normal pressure, and the hydrolysis reaction is carried out for 4 hours with stirring to obtain a sodium dinitrophenolate solution, wherein the mass fraction of the sodium dinitrophenolate is 35 wt%;

[0050] S2, putting part of the sodium dinitrophenolate solution (part of the sodium dinitrophenolate solution accounts for 30wt% of the total weight of the sodium dinitrophenolate solution) into a hydrogenation reaction kettle, and adding 1wt% sodium hydroxide aqueous solution and nickel-aluminum alloy catalyst with a metering pump, so that the weight ratio of the sodium dinitrophenolate solution to the nickel-aluminum alloy catalyst is 1:0.01, adjusting the temperature to 110°C and the pressure to 1.6MPa, starting stirring and passing hydrogen, carrying out hydrogenation reaction for 8h, entering an inorganic ceramic membrane filter for filtration to obtain a catalyst for recycling, the filtrate, i.e., 0, is a sodium diaminophenolate solution, wherein the mass fraction of sodium diaminophenolate is 20wt%;

[0051] S3, putting sulfur and a 36wt% sodium hydrosulfide aqueous solution into a sodium polysulfide preparation kettle, so that the weight ratio of sulfur to the sodium hydrosulfide aqueous solution is 1:2.5, adjusting the temperature in the kettle to 85°C and the pressure to normal pressure, and continuously stirring the reaction for 5 hours to obtain a sodium polysulfide solution, wherein the sulfur index of the sodium polysulfide is 3.6;

[0052] The sodium diaminophenolate solution and the remaining sodium dinitrophenolate solution are mixed, and then put into a sulfidation reaction kettle with the sodium polysulfide solution, so that the weight ratio of the sodium diaminophenolate solution, the remaining sodium dinitrophenolate solution and the sodium polysulfide solution is 0.4:1:1.5. The temperature in the kettle is adjusted to 105°C and the pressure is 0.15MPa. The condensation reaction is stirred for 8 hours, filtered, and the solid is dried to obtain sulfide black dye 2BR.

[0053] Example 2

[0054] A clean production process for sulfur black dye comprises the following steps:

[0055] S1. The air in the entire reaction system is replaced with nitrogen, and then a metering pump is used to put molten dinitrochlorobenzene and a sodium hydroxide aqueous solution with a concentration of 100 g / L into a hydrolysis reactor, so that the molar ratio of dinitrochlorobenzene to sodium hydroxide is 1:2, and then the temperature in the reactor is adjusted to 100° C. and the pressure is normal pressure, and the hydrolysis reaction is carried out with stirring for 2 hours to obtain a sodium dinitrophenolate solution, wherein the mass fraction of the sodium dinitrophenolate is 40wt%;

[0056] S2, putting part of the sodium dinitrophenolate solution (part of the sodium dinitrophenolate solution accounts for 60wt% of the total weight of the sodium dinitrophenolate solution) into a hydrogenation reaction kettle, and adding 0.5wt% sodium hydroxide aqueous solution and nickel-aluminum alloy catalyst with a metering pump, so that the weight ratio of the sodium dinitrophenolate solution to the catalyst is 1:0.015, adjusting the temperature to 50°C and the pressure to 3MPa, starting stirring and passing hydrogen, carrying out hydrogenation reaction for 8h, entering an inorganic ceramic membrane filter to filter and obtain a catalyst for recycling, and the filtrate is a sodium diaminophenolate solution, wherein the mass fraction of sodium diaminophenolate is 25wt%;

[0057] S3, putting sulfur and a 36wt% sodium hydrosulfide aqueous solution into a sodium polysulfide preparation kettle, so that the weight ratio of sulfur to the sodium hydrosulfide aqueous solution is 1:3, adjusting the temperature in the kettle to 80°C and the pressure to normal pressure, and continuously stirring the reaction for 8h to obtain a sodium polysulfide solution, wherein the sulfur index of the sodium polysulfide is 2.5;

[0058] The sodium diaminophenolate solution and the remaining sodium dinitrophenolate solution are mixed, and then put into a sulfidation reaction kettle with the sodium polysulfide solution, so that the weight ratio of the sodium diaminophenolate solution, the remaining sodium dinitrophenolate solution and the sodium polysulfide solution is 2:1:1.5. The temperature in the kettle is adjusted to 50°C and the pressure is 0.5MPa. The condensation reaction is stirred for 10 hours, filtered, and the solid is dried to obtain sulfide black dye 2BR.

[0059] Example 3

[0060] A clean production process for sulfur black dye comprises the following steps:

[0061] S1. The air in the entire reaction system is replaced with nitrogen, and then a metering pump is used to put molten dinitrochlorobenzene and a sodium hydroxide aqueous solution with a concentration of 300 g / L into a hydrolysis reactor, so that the molar ratio of dinitrochlorobenzene to sodium hydroxide is 1:5, and then the temperature in the reactor is adjusted to 50° C. and the pressure is normal pressure, and the hydrolysis reaction is carried out with stirring for 5 hours to obtain a sodium dinitrophenolate solution, wherein the mass fraction of the sodium dinitrophenolate is 40wt%;

[0062] S2, putting part of the sodium dinitrophenolate solution (part of the sodium dinitrophenolate solution accounts for 90wt% of the total weight of the sodium dinitrophenolate solution) into a hydrogenation reaction kettle, and adding 5wt% sodium hydroxide aqueous solution and nickel-aluminum alloy catalyst with a metering pump, so that the weight ratio of the sodium dinitrophenolate solution to the catalyst is 1:0.02, adjusting the temperature to 120°C and the pressure to 1MPa, starting stirring and passing hydrogen, carrying out hydrogenation reaction for 6h, entering an inorganic ceramic membrane filter to filter and obtain a catalyst for recycling, and the filtrate is a sodium diaminophenolate solution, wherein the mass fraction of sodium diaminophenolate is 25wt%;

[0063] S3, putting sulfur and a 36wt% sodium hydrosulfide aqueous solution into a sodium polysulfide preparation kettle, so that the weight ratio of sulfur to the sodium hydrosulfide aqueous solution is 1:3.5, adjusting the temperature in the kettle to 100° C. and the pressure to normal pressure, stirring and reacting for 4 hours to obtain a sodium polysulfide solution, wherein the sulfur index of the sodium polysulfide is 2;

[0064] The sodium diaminophenolate solution and the remaining sodium dinitrophenolate solution are mixed, and then put into a sulfidation reaction kettle with the sodium polysulfide solution, so that the weight ratio of the sodium diaminophenolate solution, the remaining sodium dinitrophenolate solution and the sodium polysulfide solution is 9:1:2. The temperature in the kettle is adjusted to 150° C. and the pressure is 0.05 MPa. The condensation reaction is stirred for 5 hours, filtered, and the solid is dried to obtain sulfide black dye 2BR.

[0065] Comparative Example 1

[0066] The existing production process of sulfur black dye includes the following steps:

[0067] S1 is the same as S1 of Example 1;

[0068] S2, sodium dinitrophenolate solution and sodium polysulfide solution (sodium polysulfide solution is the same as the sodium polysulfide solution of Example 1) are put into a sulfidation reaction kettle so that the weight ratio of sodium dinitrophenolate solution to sodium polysulfide solution is 1.4: 1, the temperature in the kettle is adjusted to 105 ° C and the pressure is 0.15 MPa, stirring for condensation reaction for 8 hours, filtering, and taking the solid and drying to obtain sulphur black dye 2BR.

[0069] The sulphur black dye 2BR prepared in Examples 1-3 and Comparative Example 1 was tested for strength, color light and color fastness according to GB / T 25808-2021. The results are shown in Table 1-2.

[0070] Table 1 Test results of intensity and color light

[0071] Test items Example 1 Example 2 Example 3 Comparative Example 1 strength / % 150 170 180 120 Color light (visual inspection) approximate approximate approximate micro

[0072] Table 2 Color fastness test results

[0073]

[0074]

[0075] It can be seen from Table 1-2 that the strength, color light and color fastness of the sulfur black dye 2BR prepared by the method of the present invention are significantly better than those of Comparative Example 1.

[0076] The above description is only a preferred specific implementation manner of the present invention, but the protection scope of the present invention is not limited thereto. Any technician familiar with the technical field can make equivalent replacements or changes according to the technical scheme and inventive concept of the present invention within the technical scope disclosed by the present invention, which should be covered by the protection scope of the present invention.

Claims

1. A clean production process for sulfur black dye, characterized in that: The steps include: S1, taking dinitrochlorobenzene and sodium hydroxide aqueous solution and mixing them, and performing hydrolysis reaction to obtain sodium dinitrophenolate solution; S2, taking part of the sodium dinitrophenolate solution, mixing it with a catalyst and a solvent, and performing a hydrogenation reaction with hydrogen to obtain a sodium diaminophenolate solution; S3, taking the sodium diaminophenolate solution, the remaining sodium dinitrophenolate solution and the sodium polysulfide solution, and carrying out a condensation reaction to obtain sulphur black dye.

2. The clean production process of sulfur black dye according to claim 1, characterized in that: In S1, the molar ratio of dinitrochlorobenzene to sodium hydroxide is 1:2-5; preferably, in S1, the concentration of the sodium hydroxide aqueous solution is 100-300 g / L.

3. The clean production process of sulfur black dye according to claim 1 or 2, characterized in that: In S1, the hydrolysis reaction temperature is 50-100°C, the time is 2-5h, and the pressure is normal pressure; preferably, in S1, the mass fraction of sodium dinitrophenolate in the sodium dinitrophenolate solution is 30-50wt%.

4. The clean production process of sulfur black dye according to any one of claims 1 to 3, characterized in that: In S2, the catalyst is at least one of a metal catalyst, a metal oxide catalyst, a molecular sieve catalyst, and a nanocatalyst; preferably, in S2, the catalyst is at least one of a nickel-aluminum alloy catalyst, a nickel catalyst, a palladium-platinum catalyst, a copper-chromium catalyst, a rhodium catalyst, and a ruthenium catalyst; preferably, in S2, the solvent is one of benzene, methanol, ethanol, acetone, and a sodium hydroxide aqueous solution; preferably, in S2, the solvent is a sodium hydroxide aqueous solution with a concentration of 0.1-10wt%.

5. The clean production process of sulfur black dye according to any one of claims 1 to 4, characterized in that: In S2, the hydrogenation reaction temperature is 50-120°C, the time is 5-12h, and the pressure is 1-3MPa; preferably, in S2, the weight ratio of the sodium dinitrophenolate solution to the catalyst is 1:0.005-0.

05.

6. The clean production process of sulfur black dye according to any one of claims 1 to 5, characterized in that: In S2, part of the sodium dinitrophenolate solution accounts for 20-99wt% of the total weight of the sodium dinitrophenolate solution; preferably, in S2, the mass fraction of sodium diaminophenolate in the sodium diaminophenolate solution is 10-40wt%.

7. The clean production process of sulfur black dye according to any one of claims 1 to 6, characterized in that: In S3, the sulfur index of sodium polysulfide is 2-5.

8. The clean production process of sulfur black dye according to any one of claims 1 to 7, characterized in that: In S3, the preparation method of sodium polysulfide solution comprises the following steps: taking sulfur and sodium hydrosulfide aqueous solution, reacting to obtain sodium polysulfide solution; preferably, the reaction temperature is 80-100°C, the reaction time is 4-8h, and the reaction pressure is normal pressure; preferably, the concentration of sodium hydrosulfide aqueous solution is 28-42wt%; preferably, the weight ratio of sulfur to sodium hydrosulfide aqueous solution is 1:2-4.

9. The clean production process of sulfur black dye according to any one of claims 1 to 8, characterized in that: In S3, the condensation reaction temperature is 50-150°C, the time is 5-10h, and the pressure is 0.05-0.5MPa.

10. The clean production process of sulfur black dye according to any one of claims 1 to 9, characterized in that: In S3, the weight ratio of the sodium diaminophenolate solution, the remaining sodium dinitrophenolate solution and the sodium polysulfide solution is 0.25-90:1:1-3.5.

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