An extractant for extracting nitro-T acid from H-acid denitrification solution

Abstract

The present invention belongs to the technical field of H-acid preparation and provides an extractant for extracting nitrotoluic acid from H-acid denitrification solution. Its preparation method includes uniformly mixing solvent oil, phenyl ether, and di-N235, and then adding a quaternary ammonium saltification reagent (benzyl chloride, n-butyl chloride, n-octane, n-dodecane) under stirring at 100-120 °C and reacting for 2-3 hours. An extractant for extracting nitronaphthalenesulfonic acid is prepared. When using this extractant to extract H-acid denitrification solution, compared with the commonly used extractants at present, mainly nitronaphthalenesulfonic acid is extracted, the alkali used for back extraction is saved by two-thirds, and the content of the back extraction solution is increased to more than 15%.

Description

Technical Field

[0001] The present invention belongs to the technical field of H-acid preparation, and particularly relates to an extractant for extracting nitro-T-acid from the H-acid denitrification filtrate. Background Art

[0002] Disclosing the information of this background art section is only intended to enhance the understanding of the overall background of the present invention, and is not necessarily to be regarded as an admission or an implication in any form that this information constitutes the prior art already known to those of ordinary skill in the art.

[0003] H-acid (sodium 1-amino-8-naphthol-3,6-disulfonate) is an important intermediate for the production of reactive dyes. At present, the production of H-acid uses refined naphthalene as raw material, and amino-T-acid is first prepared through processes such as sulfonation, nitration, denitrification, neutralization, reduction, and sodium chloride salting-out. Then, amino-T-acid is further processed through processes such as caustic fusion and acidification to produce H-acid. However, the mother liquor generated during the production of H-acid is "five-high" organic wastewater with high concentration, high acidity, high salinity, high chroma, and high toxicity. The chemical oxygen demand (COD) is as high as 80,000 - 100,000, the salt content is as high as 10% - 20%, and the chroma is as high as 4,000 - 6,000 times. It is difficult to effectively treat this "five-high" organic wastewater using traditional biochemical and physical-chemical methods; while using unconventional methods such as extraction, pyrolysis, and adsorption for treatment, the pretreatment cost alone is as high as thousands of yuan, and it is also impossible to achieve thorough and effective treatment. Currently, no domestic enterprise can effectively treat the "five-high" organic wastewater generated during H-acid production and make it meet the discharge standards. Although some wastewater can be concentrated by MVR to produce a mixed salt of ammonium sulfate and sodium chloride, this mixed salt contains a large amount of organic matter and is difficult to purify, and can only be treated as solid waste.

[0004] To solve this problem, it has been reported that a complexing extractant is used to extract nitro-naphthalenesulfonic acid from the denitrification solution. The selected extractants are sulfonated kerosene and NN235, and some also add tributyl phosphate. The disadvantage of this extractant is that when extracting nitro-naphthalenesulfonic acid, a considerable amount of sulfuric acid is simultaneously extracted, the concentration of the stripping solution is low, and a large amount of alkali is used. Summary of the Invention

[0005] In order to solve the above problems, the present invention provides an extractant for extracting nitro-T-acid from the H-acid denitrification filtrate.

[0006] In order to achieve the above object, the present invention adopts the following technical solutions:

[0007] In the first aspect of the present invention, an extractant for extracting nitro T-acid from H-acid denitrification solution is provided, which is composed of raw materials in the following weight percentages: 200# solvent oil or sulfonated kerosene 30%-50%, phenyl ether 25%-35%, N235 quaternary ammonium salt 25%-35%, and the sum of the percentages of each raw material is 100%;

[0008] The N235 quaternary ammonium salt is at least one of benzyl N235 quaternary ammonium salt, n-butyl N235 quaternary ammonium salt, n-hexyl N235 n-octyl quaternary ammonium salt, and dodecyl N235 quaternary ammonium salt.

[0009] In the second aspect of the present invention, a preparation method of an extractant for extracting nitro T-acid from H-acid denitrification solution is provided, including:

[0010] Mix the solvent oil, phenyl ether, and N235 evenly, then add the quaternization reagent under stirring, and react at 100-150°C for 2-3 hours to obtain it;

[0011] Among them, the quaternization reagent is at least one of benzyl chloride, n-butyl chloride, n-octyl chloride, and n-dodecyl chloride.

[0012] In the third aspect of the present invention, the above-mentioned extractant is provided for use in extracting nitro T-acid from H-acid denitrification solution.

[0013] Advantages of the present invention

[0014] (1) The quaternary ammonium salt type extractant of the present invention is used to extract nitro naphthalenesulfonic acid from the denitrification solution. The amount of sulfuric acid extracted is very small, and the amount of alkali used for back extraction is small, only about 1 / 3 of that of ordinary extractants during back extraction. The content of nitro naphthalenesulfonic acid in the back extraction solution is about 16%, reducing the amount of back extraction solution, reducing the amount of amino T-acid mother liquor during reduction, and reducing the cost.

[0015] (2) The preparation method of the present invention is simple, highly practical, and easy to promote. Detailed implementation manners

[0016] It should be noted that the following detailed descriptions are all exemplary and are intended to provide further explanations of the present invention. Unless otherwise specified, all technical and scientific terms used in the present invention have the same meanings as those commonly understood by those of ordinary skill in the technical field to which the present invention belongs.

[0017] An extractant for extracting nitro T-acid from H-acid denitrification filtrate

[0018] 1) The selected extractant components are common extractant components: sulfonated kerosene (or 200# solvent oil), N235, and phenyl butyl ether (or diphenyl ether benzyl ether).

[0019] 2) The new component is a quaternary ammonium salt: aryl NN235, quaternary ammonium salt. The common aryl groups are phenyl and benzyl, and the preferred one is benzyl N235 quaternary ammonium salt.

[0020] Alkyl N235 quaternary ammonium salt. The common alkyl groups are n-butyl, n-octyl, and n-dodecyl, and the preferred one is n-dodecyl N235 quaternary ammonium salt.

[0021] 3) In the extractant prepared with sulfonated kerosene, N235, and ether solvent, add aryl or alkyl chloride in proportion and react for several hours. N235 reacts with the chloride to form a quaternary ammonium salt. The molar ratio of chloride to NN235 is 1:1 - 1.5, and the preferred ratio is 1:1.25.

[0022] 4) The reaction temperature for forming the quaternary ammonium salt is 100 - 150 °C, preferably 120 °C, and the reaction time is 3 hours.

[0023] In some embodiments, the extractant for extracting nitronaphthalenesulfonic acid from the H-acid denitrification solution includes the following components: 200# solvent oil (or sulfonated kerosene), phenyl ether, and N235 quaternary ammonium salt.

[0024] In some embodiments, the phenyl ether includes diphenyl ether, benzyl phenyl ether, butyl phenyl ether, and octyl phenyl ether.

[0025] In some embodiments, the N235 quaternary ammonium salt includes benzyl N235 quaternary ammonium salt, n-butyl N235 quaternary ammonium salt, n-octyl N235 n-octyl quaternary ammonium salt, and n-dodecyl N235 quaternary ammonium salt.

[0026] In some embodiments, the N235 quaternary ammonium salt reagent is n-butane chloride or bromide, n-octane, n-dodecane, and the benzyl quaternary ammonium salt reagent is benzyl chloride.

[0027] In some embodiments, the proportion of 200# solvent oil or (sulfonated kerosene) in the extractant is 30% - 50%, and the preferred proportion is 40%.

[0028] In some embodiments, the proportion of phenyl ether in the extraction is 25% - 35%, and the preferred proportion is 30%.

[0029] In some embodiments, the proportion of N235 quaternary ammonium salt in the extractant is 25% - 35%, and the preferred proportion is 30%.

[0030] The following combines specific embodiments to further elaborate on the present invention. It should be noted that the specific embodiments are explanations rather than limitations of the present invention.

[0031] Example 1: Preparation of extractant. 400 parts of 200# solvent oil, 300 parts of benzyl ether, 240 parts of N235, and 60 parts of benzyl chloride were mixed and reacted at 100 - 110°C for 2 hours. The product is the extractant for nitronaphthalenesulfonic acid.

[0032] Extraction of denitrification solution. 100 parts of denitrification filtrate were taken, with a nitronaphthalenesulfonic acid content of 7.16% and an acidity of 35.54% (calculated as sulfuric acid). It was extracted with 250 parts of extractant. The post - extraction liquid was 93.6 parts, with a nitronaphthalenesulfonic acid content of 0.58% and an acidity of 32.44% (calculated as sulfuric acid). The extraction liquid was back - extracted with a sodium hydroxide solution with a content of 24.33%. The back - extraction liquid was 41.6 parts, with a nitronaphthalenesulfonic acid content of 15.6%.

[0033] Example 2: 300 parts of the extractant from Example 1, 100 parts of denitrification filtrate (the same as in Example 1), the acidity of the post - extraction water was 32.12% (calculated as sulfuric acid), and the nitronaphthalenesulfonic acid content was 0.32%. The extraction liquid was back - extracted with 24.33% sodium hydroxide. The back - extraction liquid was 39.6 parts, with a nitronaphthalenesulfonic acid content of 15.8%

[0034] Example 3: Preparation of extractant. 400 parts of sulfonated kerosene, 300 parts of phenyl butyl ether, 240 parts of N235, and 60 parts of benzyl chloride were reacted at 100 - 110°C for 2 hours.

[0035] Extraction of denitrification product. 100 parts of denitrification filtrate, with a nitronaphthalenesulfonic acid content of 8.2% and an acidity of 36.3% (calculated as sulfuric acid in terms of sulfuric acid agent), 300 parts of extractant were used for extraction. The post - extraction liquid was 91.3 parts, with a nitronaphthalenesulfonic acid content of 0.36% and an acidity of 33.62% (calculated as sulfuric acid). The extraction liquid was back - extracted with a sodium hydroxide solution with a content of 25.2%. The back - extraction liquid was 46.7 parts, with a nitronaphthalenesulfonic acid content of 16.8%.

[0036] Example 4: Preparation of extractant. 400 parts of 200# solvent oil, 300 parts of phenyl butyl ether, 240 parts of NN235, and 100 parts of chlorododecane were mixed and reacted at 110 - 120°C for 3 hours.

[0037] Extraction of denitrification product: 100 parts of denitrification filtrate, with a nitronaphthalenesulfonic acid content of 7.6% and an acidity of 35.8% (calculated as sulfuric acid agent), 280 parts of extractant were used for extraction. The post - extraction liquid was 93.6 parts, with a nitronaphthalenesulfonic acid content of 0.26% and sulfuric acid of 32.96% (calculated as sulfuric acid agent). Back - extraction of the extraction liquid: It was back - extracted with a sodium hydroxide solution with a content of 27.5%. The back - extraction liquid was 42.3 parts, with a nitronaphthalenesulfonic acid content of 17.2%.

[0038] Comparative Example 1

[0039] The difference from Example 1 is that benzyl chloride was not added. 400 parts of 200# solvent oil, 300 parts of benzyl ether, and 240 parts of N235 were mixed evenly to obtain the extractant.

[0040] Denitrification liquid extraction: Take 100 parts of the denitrification filtrate, with a nitro-naphthalene sulfonic acid content of 7.16% and an acidity of 35.54% (calculated as sulfuric acid). Extract with 250 parts of the extractant. The post-extraction liquid is 75 parts, with a nitro-naphthalene sulfonic acid content of 1.08% and an acidity of 26.7% (calculated as sulfuric acid). The extraction liquid is back-extracted with a sodium hydroxide solution with a content of 24.33%. The back-extraction liquid is 117 parts, with a nitro-naphthalene sulfonic acid content of 5.8%.

[0041] Comparative Example 2

[0042] The difference from Example 1 is that methyltriethylammonium chloride is used to replace N235 to obtain a quaternary ammonium salt extractant.

[0043] Denitrification liquid extraction: Take 100 parts of the denitrification filtrate, with a nitro-naphthalene sulfonic acid content of 7.16% and an acidity of 35.54% (calculated as sulfuric acid). Extract with 250 parts of the extractant. The post-extraction liquid is 92.8 parts, with a nitro-naphthalene sulfonic acid content of 0.29% and an acidity of 32.96% (calculated as sulfuric acid). The extraction liquid is back-extracted with a sodium hydroxide solution with a content of 24.33%. The back-extraction liquid is 45.6 parts, with a nitro-naphthalene sulfonic acid content of 14.82%.

[0044] The above are only the preferred embodiments of the present invention and are not used to limit the present invention. For those skilled in the art, the present invention can have various changes and modifications. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included within the protection scope of the present invention.

Claims

1. A preparation method of an extractant for extracting nitro-T acid from H-acid denitrification solution, characterized in that, Comprising: Mix 200# solvent naphtha or sulfonated kerosene, phenyl ether, and N235 evenly, then add the quaternary ammonium saltification reagent under stirring, and react at 100 - 150 °C for 2 - 3 hours to obtain it; The quaternary ammonium saltification reagent is at least one of benzyl chloride, n-butyl chloride, n-octyl chloride, and n-dodecyl chloride; The molar ratio of N235 to the quaternary ammonium saltification reagent is 1:1 - 1.5; N235 reacts with the quaternary ammonium saltification reagent to obtain N235 quaternary ammonium salt; The extractant for extracting nitro T-acid from H-acid denitrification solution consists of raw materials with the following weight percentages: 200# solvent naphtha or sulfonated kerosene 30% - 50%, phenyl ether 25% - 35%, N235 quaternary ammonium salt 25% - 35%, and the sum of the percentages of each raw material is 100%; The N235 quaternary ammonium salt is at least one of benzyl N235 quaternary ammonium salt, n-butyl N235 quaternary ammonium salt, n-octyl N235 quaternary ammonium salt, and n-dodecyl N235 quaternary ammonium salt.

2. The preparation method of the extractant for extracting nitro-T acid from H acid denitrification solution according to claim 1, characterized in that, The extractant consists of raw materials with the following weight percentages: 200# solvent naphtha or sulfonated kerosene 40%, phenyl ether 30%, and N235 quaternary ammonium salt 30%.

3. The preparation method of the extractant for extracting nitro-T acid from H-acid denitrification solution according to claim 1, characterized in that, The phenyl ether is selected from diphenyl ether, benzyl phenyl ether, butyl phenyl ether, and octyl phenyl ether.

4. The preparation method of the extractant for extracting nitro T-acid from H-acid denitrification solution according to claim 1, characterized in that, The molar ratio of N235 to the quaternary ammonium saltification reagent is 1:1.

25.

5. The preparation method of the extractant for extracting nitro-T acid from H-acid denitrification solution according to claim 1, characterized in that, The reaction time is 3 hours.

6. The preparation method of the extractant for extracting nitrotoluic acid from H-acid denitrification solution as described in claim 1, characterized in that, The reaction temperature is 120 °C.

7. The extractant prepared by the preparation method according to any one of claims 1 - 6.

8. Use of the extractant according to claim 7 in extracting nitro T-acid from H-acid denitrification solution.