CN113735737B - Preparation method of p-benzoquinone dioxime - Google Patents
Preparation method of p-benzoquinone dioxime Download PDFInfo
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- CN113735737B CN113735737B CN202110957278.8A CN202110957278A CN113735737B CN 113735737 B CN113735737 B CN 113735737B CN 202110957278 A CN202110957278 A CN 202110957278A CN 113735737 B CN113735737 B CN 113735737B
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- DZCCLNYLUGNUKQ-UHFFFAOYSA-N n-(4-nitrosophenyl)hydroxylamine Chemical compound ONC1=CC=C(N=O)C=C1 DZCCLNYLUGNUKQ-UHFFFAOYSA-N 0.000 title claims abstract description 53
- 238000002360 preparation method Methods 0.000 title claims abstract description 14
- 238000006243 chemical reaction Methods 0.000 claims abstract description 83
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims abstract description 64
- 239000003960 organic solvent Substances 0.000 claims abstract description 40
- QQZWEECEMNQSTG-UHFFFAOYSA-N Ethyl nitrite Chemical compound CCON=O QQZWEECEMNQSTG-UHFFFAOYSA-N 0.000 claims abstract description 39
- WTDHULULXKLSOZ-UHFFFAOYSA-N Hydroxylamine hydrochloride Chemical compound Cl.ON WTDHULULXKLSOZ-UHFFFAOYSA-N 0.000 claims abstract description 36
- 239000011261 inert gas Substances 0.000 claims abstract description 34
- KMGMCLWJFCGWFI-UHFFFAOYSA-N chembl3276923 Chemical compound ON=C1C=CC(=O)C=C1 KMGMCLWJFCGWFI-UHFFFAOYSA-N 0.000 claims abstract description 33
- 238000007034 nitrosation reaction Methods 0.000 claims abstract description 29
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N Phenol Chemical compound OC1=CC=CC=C1 ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 claims abstract description 25
- 238000000034 method Methods 0.000 claims abstract description 25
- 238000006146 oximation reaction Methods 0.000 claims abstract description 21
- 239000002351 wastewater Substances 0.000 claims abstract description 16
- 238000000354 decomposition reaction Methods 0.000 claims abstract description 9
- 238000004519 manufacturing process Methods 0.000 claims abstract description 8
- 230000003647 oxidation Effects 0.000 claims abstract description 7
- 238000007254 oxidation reaction Methods 0.000 claims abstract description 7
- 238000007323 disproportionation reaction Methods 0.000 claims abstract description 6
- 239000007788 liquid Substances 0.000 claims description 69
- VEXZGXHMUGYJMC-UHFFFAOYSA-N Hydrochloric acid Chemical compound Cl VEXZGXHMUGYJMC-UHFFFAOYSA-N 0.000 claims description 56
- IXCSERBJSXMMFS-UHFFFAOYSA-N hydrogen chloride Substances Cl.Cl IXCSERBJSXMMFS-UHFFFAOYSA-N 0.000 claims description 34
- 229910000041 hydrogen chloride Inorganic materials 0.000 claims description 34
- 238000001704 evaporation Methods 0.000 claims description 30
- 230000008020 evaporation Effects 0.000 claims description 30
- 238000002156 mixing Methods 0.000 claims description 18
- IJGRMHOSHXDMSA-UHFFFAOYSA-N Atomic nitrogen Chemical compound N#N IJGRMHOSHXDMSA-UHFFFAOYSA-N 0.000 claims description 16
- 239000000243 solution Substances 0.000 claims description 16
- 239000000706 filtrate Substances 0.000 claims description 13
- 239000012298 atmosphere Substances 0.000 claims description 12
- 238000001914 filtration Methods 0.000 claims description 12
- 230000035484 reaction time Effects 0.000 claims description 12
- 238000005406 washing Methods 0.000 claims description 10
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 10
- 238000004821 distillation Methods 0.000 claims description 9
- 239000011259 mixed solution Substances 0.000 claims description 9
- 238000001035 drying Methods 0.000 claims description 7
- 229910052757 nitrogen Inorganic materials 0.000 claims description 7
- 239000007787 solid Substances 0.000 claims description 7
- 238000011049 filling Methods 0.000 claims description 6
- 230000002401 inhibitory effect Effects 0.000 claims description 5
- 239000003513 alkali Substances 0.000 claims description 3
- 230000008569 process Effects 0.000 abstract description 11
- 239000006227 byproduct Substances 0.000 abstract description 7
- 238000003786 synthesis reaction Methods 0.000 abstract description 6
- 239000002994 raw material Substances 0.000 abstract description 5
- 238000007086 side reaction Methods 0.000 abstract description 5
- 230000002378 acidificating effect Effects 0.000 abstract description 4
- 230000009471 action Effects 0.000 abstract description 4
- 230000015572 biosynthetic process Effects 0.000 abstract description 4
- 238000002844 melting Methods 0.000 abstract description 3
- 230000008018 melting Effects 0.000 abstract description 3
- 235000019441 ethanol Nutrition 0.000 description 15
- AZQWKYJCGOJGHM-UHFFFAOYSA-N 1,4-benzoquinone Chemical compound O=C1C=CC(=O)C=C1 AZQWKYJCGOJGHM-UHFFFAOYSA-N 0.000 description 10
- LPXPTNMVRIOKMN-UHFFFAOYSA-M sodium nitrite Chemical compound [Na+].[O-]N=O LPXPTNMVRIOKMN-UHFFFAOYSA-M 0.000 description 6
- 239000002904 solvent Substances 0.000 description 5
- JSTCPNFNKICNNO-UHFFFAOYSA-N 4-nitrosophenol Chemical compound OC1=CC=C(N=O)C=C1 JSTCPNFNKICNNO-UHFFFAOYSA-N 0.000 description 4
- MWUXSHHQAYIFBG-UHFFFAOYSA-N Nitric oxide Chemical compound O=[N] MWUXSHHQAYIFBG-UHFFFAOYSA-N 0.000 description 4
- 238000009833 condensation Methods 0.000 description 4
- 230000005494 condensation Effects 0.000 description 4
- LZDSILRDTDCIQT-UHFFFAOYSA-N dinitrogen trioxide Chemical compound [O-][N+](=O)N=O LZDSILRDTDCIQT-UHFFFAOYSA-N 0.000 description 4
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 238000001816 cooling Methods 0.000 description 3
- 238000001514 detection method Methods 0.000 description 3
- 229920001971 elastomer Polymers 0.000 description 3
- 238000005286 illumination Methods 0.000 description 3
- 238000005259 measurement Methods 0.000 description 3
- 239000000843 powder Substances 0.000 description 3
- 239000000047 product Substances 0.000 description 3
- 239000005060 rubber Substances 0.000 description 3
- 235000010288 sodium nitrite Nutrition 0.000 description 3
- 230000002194 synthesizing effect Effects 0.000 description 3
- 238000004073 vulcanization Methods 0.000 description 3
- VTYYLEPIZMXCLO-UHFFFAOYSA-L Calcium carbonate Chemical compound [Ca+2].[O-]C([O-])=O VTYYLEPIZMXCLO-UHFFFAOYSA-L 0.000 description 2
- GWEVSGVZZGPLCZ-UHFFFAOYSA-N Titan oxide Chemical compound O=[Ti]=O GWEVSGVZZGPLCZ-UHFFFAOYSA-N 0.000 description 2
- 239000000853 adhesive Substances 0.000 description 2
- 230000001070 adhesive effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 2
- 229910001873 dinitrogen Inorganic materials 0.000 description 2
- 239000001257 hydrogen Substances 0.000 description 2
- 229910052739 hydrogen Inorganic materials 0.000 description 2
- -1 hydrogen ions Chemical class 0.000 description 2
- 239000003112 inhibitor Substances 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000001737 promoting effect Effects 0.000 description 2
- 239000011347 resin Substances 0.000 description 2
- 229920005989 resin Polymers 0.000 description 2
- 239000000126 substance Substances 0.000 description 2
- SMZOUWXMTYCWNB-UHFFFAOYSA-N 2-(2-methoxy-5-methylphenyl)ethanamine Chemical compound COC1=CC=C(C)C=C1CCN SMZOUWXMTYCWNB-UHFFFAOYSA-N 0.000 description 1
- NIXOWILDQLNWCW-UHFFFAOYSA-N 2-Propenoic acid Natural products OC(=O)C=C NIXOWILDQLNWCW-UHFFFAOYSA-N 0.000 description 1
- MGWGWNFMUOTEHG-UHFFFAOYSA-N 4-(3,5-dimethylphenyl)-1,3-thiazol-2-amine Chemical compound CC1=CC(C)=CC(C=2N=C(N)SC=2)=C1 MGWGWNFMUOTEHG-UHFFFAOYSA-N 0.000 description 1
- 229920000089 Cyclic olefin copolymer Polymers 0.000 description 1
- 229920000181 Ethylene propylene rubber Polymers 0.000 description 1
- 244000043261 Hevea brasiliensis Species 0.000 description 1
- AVXURJPOCDRRFD-UHFFFAOYSA-N Hydroxylamine Chemical compound ON AVXURJPOCDRRFD-UHFFFAOYSA-N 0.000 description 1
- GRYLNZFGIOXLOG-UHFFFAOYSA-N Nitric acid Chemical compound O[N+]([O-])=O GRYLNZFGIOXLOG-UHFFFAOYSA-N 0.000 description 1
- IOVCWXUNBOPUCH-UHFFFAOYSA-N Nitrous acid Chemical compound ON=O IOVCWXUNBOPUCH-UHFFFAOYSA-N 0.000 description 1
- CBENFWSGALASAD-UHFFFAOYSA-N Ozone Chemical compound [O-][O+]=O CBENFWSGALASAD-UHFFFAOYSA-N 0.000 description 1
- LGRFSURHDFAFJT-UHFFFAOYSA-N Phthalic anhydride Natural products C1=CC=C2C(=O)OC(=O)C2=C1 LGRFSURHDFAFJT-UHFFFAOYSA-N 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 230000003213 activating effect Effects 0.000 description 1
- 239000012670 alkaline solution Substances 0.000 description 1
- JHIWVOJDXOSYLW-UHFFFAOYSA-N butyl 2,2-difluorocyclopropane-1-carboxylate Chemical compound CCCCOC(=O)C1CC1(F)F JHIWVOJDXOSYLW-UHFFFAOYSA-N 0.000 description 1
- 229920005549 butyl rubber Polymers 0.000 description 1
- 229910000019 calcium carbonate Inorganic materials 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 239000003795 chemical substances by application Substances 0.000 description 1
- 238000004132 cross linking Methods 0.000 description 1
- 239000003431 cross linking reagent Substances 0.000 description 1
- 239000006185 dispersion Substances 0.000 description 1
- 239000012990 dithiocarbamate Substances 0.000 description 1
- 150000004659 dithiocarbamates Chemical class 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000010292 electrical insulation Methods 0.000 description 1
- 230000007613 environmental effect Effects 0.000 description 1
- 230000002349 favourable effect Effects 0.000 description 1
- 239000000835 fiber Substances 0.000 description 1
- 239000012467 final product Substances 0.000 description 1
- 239000011521 glass Substances 0.000 description 1
- 238000010438 heat treatment Methods 0.000 description 1
- 239000012943 hotmelt Substances 0.000 description 1
- 239000012535 impurity Substances 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 229910052751 metal Inorganic materials 0.000 description 1
- 239000002184 metal Substances 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 229920003052 natural elastomer Polymers 0.000 description 1
- 229920001194 natural rubber Polymers 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 229910017604 nitric acid Inorganic materials 0.000 description 1
- JCXJVPUVTGWSNB-UHFFFAOYSA-N nitrogen dioxide Inorganic materials O=[N]=O JCXJVPUVTGWSNB-UHFFFAOYSA-N 0.000 description 1
- 230000009935 nitrosation Effects 0.000 description 1
- 239000007800 oxidant agent Substances 0.000 description 1
- 230000001590 oxidative effect Effects 0.000 description 1
- 229920000728 polyester Polymers 0.000 description 1
- 238000006116 polymerization reaction Methods 0.000 description 1
- 239000005077 polysulfide Substances 0.000 description 1
- 229920001021 polysulfide Polymers 0.000 description 1
- 150000008117 polysulfides Polymers 0.000 description 1
- 239000003381 stabilizer Substances 0.000 description 1
- 229920003048 styrene butadiene rubber Polymers 0.000 description 1
- QAOWNCQODCNURD-UHFFFAOYSA-N sulfuric acid Substances OS(O)(=O)=O QAOWNCQODCNURD-UHFFFAOYSA-N 0.000 description 1
- 238000001308 synthesis method Methods 0.000 description 1
- 238000010189 synthetic method Methods 0.000 description 1
- 150000003557 thiazoles Chemical class 0.000 description 1
- 239000004408 titanium dioxide Substances 0.000 description 1
- 239000004636 vulcanized rubber Substances 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C249/00—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton
- C07C249/04—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of oximes
- C07C249/06—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of oximes by nitrosation of hydrocarbons or substituted hydrocarbons
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C249/00—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton
- C07C249/04—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of oximes
- C07C249/08—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of oximes by reaction of hydroxylamines with carbonyl compounds
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C249/00—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton
- C07C249/04—Preparation of compounds containing nitrogen atoms doubly-bound to a carbon skeleton of oximes
- C07C249/14—Separation; Purification; Stabilisation; Use of additives
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The application provides a preparation method of p-benzoquinone dioxime, wherein ethyl nitrite and phenol are subjected to nitrosation reaction under the action of an acidic reaction promoter to generate intermediate p-benzoquinone monooxime and byproduct ethanol, then the intermediate p-benzoquinone monooxime is directly subjected to oximation reaction with hydroxylamine hydrochloride to generate p-benzoquinone dioxime, and the whole reaction process is completed in an organic solvent; the discharge of production wastewater is reduced, and the requirements of green production are met; the ethanol which is a byproduct obtained by the nitrosation reaction can be finally distilled and recovered together with the organic solvent, so that the utilization rate of raw materials is improved; the whole synthesis process adopts a mode of isolating inert gas from air, avoids disproportionation and decomposition of ethyl nitrite and oxidation of intermediate p-benzoquinone monooxime, reduces side reactions, improves the conversion rate of the reaction, and further improves the yield and purity of p-benzoquinone dioxime, wherein the yield is 85.0-95.0%, the purity is more than or equal to 99.0wt%, and the melting point is 250-255 ℃.
Description
Technical Field
The invention relates to the technical field of synthesis and preparation of p-benzoquinone dioxime, in particular to a preparation method of p-benzoquinone dioxime.
Background
The p-benzoquinone dioxime is a cross-linking agent with excellent performance, has the characteristics of easy dispersion in rubber materials, high vulcanization speed, high stretching strength of vulcanized rubber, heat resistance, weather resistance, ozone resistance, good electrical insulation performance and the like, and is widely applied to the rubber industry. The p-benzoquinone dioxime can be used as an acrylic acid polymerization inhibitor, can improve the thermal resistance of polyester fiber tire cords, and can also be used as an adhesive for hot melt connection of metal and glass, an olefin copolymer crosslinking regulator, an organic monomer stabilizer, a self-vulcanization type adhesive and an activating effect on an oxidant. The p-benzoquinone dioxime is particularly suitable for butyl rubber, natural rubber, ethylene propylene rubber, styrene butadiene rubber, polysulfide rubber and the like with high stretching strength and high vulcanization speed. However, the critical temperature of the p-benzoquinone dioxime is lower, the p-benzoquinone dioxime has a scorching tendency, and certain scorch inhibitors (such as phthalic anhydride and NA) and accelerators (such as thiurams, thiazoles and dithiocarbamates) can be added to effectively improve the operation safety. Meanwhile, the p-benzoquinone dioxime has pollution, and about five parts of titanium dioxide can be added to prevent or improve the pollution.
In recent years, methods for synthesizing p-benzoquinone dioxime mainly include:
the first method comprises the following steps: sodium nitrite and phenol dissolved in 30 percent NaOH solution are subjected to nitrosation reaction to generate p-benzoquinone monooxime at 0 ℃ in the presence of concentrated sulfuric acid with certain concentration, then the prepared p-benzoquinone monooxime is added with hydroxylamine for oximation to prepare a final product p-benzoquinone dioxime, the purity and the yield of the product are both limited by the synthesis method, the purity is generally less than or equal to 90 percent, more impurities are contained, and the yield is generally less than or equal to 60 percent. The concrete body is as follows: 1) Nitrous acid generated by sodium nitrite when meeting acid is extremely unstable, and is easily disproportionated and decomposed by heating, illumination or contacting with air to generate disproportionated products nitric acid and nitric oxide and decomposed products dinitrogen trioxide, and the dinitrogen trioxide is rapidly decomposed into nitric oxide and nitrogen dioxide, so that the yield and the quality of the p-benzoquinone dioxime are greatly reduced. 2) In the process of carrying out nitrosation reaction to generate benzoquinone monooxime, air in the reactor can oxidize part of benzoquinone monooxime to generate resin, which affects the quality of benzoquinone monooxime and further affects the quality of benzoquinone dioxime.
The second method comprises the following steps: p-benzoquinone and hydroxylamine hydrochloride are used as raw materials, calcium carbonate is used as a catalyst, and the p-benzoquinone dioxime is synthesized through one step at a certain temperature. Because the p-benzoquinone is a crystalline solid with adsorbability, the p-benzoquinone is very easy to be adsorbed to a human body to cause discomfort of the human body in the using process, and is not beneficial to industrial production. In addition, the p-benzoquinone dioxime synthesized by the method has dark appearance color and low purity.
Disclosure of Invention
The invention aims to provide a preparation method of p-benzoquinone dioxime, which adopts ethyl nitrite to replace sodium nitrite in the traditional process, adopts organic solvent to replace water as solvent, adopts inert gas to isolate air in the reaction process, and adopts hydrochloric acid as a reaction accelerator for providing hydrogen ions and promoting nitrosation reaction; nitrosation reaction is carried out on ethyl nitrite and phenol under the action of an acidic reaction promoter to generate an intermediate p-benzoquinone monooxime and byproduct ethanol, then the intermediate p-benzoquinone monooxime directly carries out oximation reaction with hydroxylamine hydrochloride to generate p-benzoquinone dioxime, and the whole reaction process is completed in an organic solvent; the byproduct ethanol obtained by the nitrosation reaction can be used as an organic solvent and finally distilled, condensed and recycled, so that the utilization rate of raw materials is improved, the discharge of production wastewater is reduced, and the requirement of green production is met; in addition, the whole synthesis process adopts a mode of isolating air by inert gas, avoids disproportionation and decomposition of ethyl nitrite and oxidation of intermediate p-benzoquinone monooxime, reduces side reactions, improves the conversion rate of the reaction, and further improves the yield and purity of p-benzoquinone dioxime.
In order to solve the technical problems, the technical scheme provided by the invention is as follows:
a preparation method of p-benzoquinone dioxime comprises the following steps of:
1) Dissolving ethyl nitrite in an organic solvent in a reaction kettle, and uniformly mixing to obtain an intermediate liquid A;
2) Adding phenol into the intermediate liquid A prepared in the step 1), and uniformly mixing to obtain an intermediate liquid B;
3) Vacuumizing the reaction kettle after the step 2) is finished, and then filling inert gas into the reaction kettle;
4) Dissolving concentrated hydrochloric acid in an organic solvent, and uniformly mixing to obtain a mixed solution of hydrogen chloride and the organic solvent;
5) Nitrosation reaction: dropwise adding the mixed solution of hydrogen chloride and an organic solvent prepared in the step 4) into the intermediate liquid B in the reaction kettle, and carrying out a chemical reaction on ethyl nitrite, phenol and hydrogen chloride in an inert gas atmosphere to generate p-benzoquinone monooxime, thus obtaining an intermediate liquid C;
6) Oximation reaction: adding hydroxylamine hydrochloride solid into the intermediate liquid C prepared in the step 5), and carrying out chemical reaction on p-benzoquinone monooxime and hydroxylamine hydrochloride in an inert gas atmosphere to generate p-benzoquinone dioxime, thus obtaining an intermediate liquid D;
7) Distilling the intermediate liquid D prepared in the step 6), condensing vapor generated by evaporation to obtain condensate, recovering the organic solvent from the condensate, and obtaining the residual liquid after evaporation;
8) Filtering the residual evaporation solution prepared in the step 7), and obtaining filter residue and filtrate after filtering;
9) And (3) sequentially washing, centrifugally dewatering and drying the filter residue prepared in the step 8) to obtain powdery benzoquinone dioxime.
Preferably, in the step 1), the temperature of air in a kettle cavity in the reaction kettle is 0-5 ℃, the organic solvent is absolute ethyl alcohol, and the mass of ethyl nitrite is =1 (3-6).
Preferably, in the step 2), the amount of ethyl nitrite to phenol = (1 to 1.3) to 1.
Preferably, in the step 3), the inert gas is nitrogen gas, so that the inert gas is used for isolating air and inhibiting disproportionation and decomposition of ethyl nitrite and oxidation of intermediate p-benzoquinone monooxime.
Preferably, in the step 4), the mass of hydrogen chloride to the mass of phenol = (1 to 2) to 1, the organic solvent is absolute ethyl alcohol, and the mass of hydrogen chloride to the mass of organic solvent =1 (1 to 5).
Preferably, in the step 5), when the temperature of the intermediate liquid B in the reaction kettle is reduced to 0 ℃, the mixed solution of the hydrogen chloride and the organic solvent prepared in the step 4) is dripped into the intermediate liquid B in the reaction kettle, and the dripping is completed within 1.5 h-3 h;
the reaction temperature of the nitrosation reaction is 0-8 ℃, and the reaction time of the nitrosation reaction is 0.5-2 h.
Preferably, in the step 6), the mass of hydroxylamine hydrochloride is that the mass of phenol = (1 to 1.3) is 1;
the reaction temperature of the oximation reaction is 60-75 ℃, and the reaction time of the oximation reaction is 2-4 h.
Preferably, in step 7), the evaporation temperature during distillation is 70 ℃ to 85 ℃.
Preferably, the filtrate obtained in the step 8) and the waste water generated by the water washing in the step 9) are mixed, then neutralized by alkali liquor, and then evaporated and condensed to remove the hydrogen chloride in the filtrate and the waste water, wherein the evaporation temperature is 90-105 ℃.
The application obtains the following beneficial technical effects:
(1) Adopt absolute ethyl alcohol to regard as the solvent of ethyl nitrite and concentrated hydrochloric acid respectively in this application, whole synthetic process only has the introduction of a small amount of water in the concentrated hydrochloric acid, and organic solvent absolute ethyl alcohol accessible distillation, the mode of condensation is retrieved, and this kind of synthetic method has reduced the production of waste water to a certain extent, has reduced waste water treatment's the degree of difficulty, is favorable to environmental protection. According to the method for synthesizing the p-benzoquinone dioxime, the introduction of a water solvent is avoided, so that the output of wastewater is reduced, and the treatment pressure of the wastewater is reduced.
(2) In the method, ethyl nitrite is used as a nitrosation agent, hydrochloric acid is used as a reaction promoter for providing hydrogen ions and promoting nitrosation reaction, nitrosation reaction is carried out between ethyl nitrite and phenol under the action of an acidic reaction promoter to generate intermediate p-benzoquinone monooxime, and ethanol is used as a byproduct; the byproduct ethanol can be distilled and recycled together with ethanol used as an organic solvent, so that the utilization rate of raw materials is improved, and the production cost is reduced; the hydrogen chloride in the filtrate and the waste water generated by water washing can be neutralized by alkaline liquor, and then the hydrogen chloride is removed by a filter residue mode through evaporation and condensation.
(3) In the application, because ethyl nitrite is heated or is easily decomposed by illumination, and the steam is unstable in contact with air, the mode of replacing the air in the reaction kettle by inert gas nitrogen is adopted, and the inert gas is adopted to isolate ethyl nitrite from the air, so that the disproportionation and decomposition of ethyl nitrite caused by air are inhibited, the generation of side reactions is reduced, the safety of the synthesis reaction is improved, and the yield and the quality of p-benzoquinone dioxime are improved.
(4) The method adopts the inert gas nitrogen to replace the air in the reaction system, because the p-benzoquinone monooxime is extremely unstable and generates quinone substances by side reactions under the conditions of temperature, air, illumination and the like, the p-benzoquinone monooxime is easily oxidized to generate resin when meeting the air, and the contact of the p-benzoquinone monooxime and the air is avoided by introducing the inert gas nitrogen, so that the oxidation of the p-benzoquinone monooxime is avoided, the quality of the p-benzoquinone monooxime is improved, and the quality and the yield of the p-benzoquinone dioxime are indirectly improved.
(5) The p-benzoquinone dioxime prepared by the preparation method provided by the application has high yield, purity and melting point, the yield is 85.0-95.0%, the purity is more than or equal to 99.0wt%, the melting point is 250-255 ℃, and meanwhile, the discharge of productive wastewater is reduced.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the embodiments of the present invention, and it is obvious that the described embodiments are part of the embodiments of the present invention, but not all of the embodiments. All other embodiments, which can be obtained by a person skilled in the art without any inventive step based on the embodiments of the present invention, are within the scope of the present invention.
The application provides a preparation method of p-benzoquinone dioxime, which comprises the following steps in sequence:
1) Dissolving ethyl nitrite in an organic solvent in a reaction kettle, and uniformly mixing to obtain an intermediate liquid A;
2) Adding phenol into the intermediate liquid A prepared in the step 1), and uniformly mixing to obtain an intermediate liquid B;
3) Vacuumizing the reaction kettle after the step 2) is finished, and then filling inert gas into the reaction kettle;
4) Dissolving concentrated hydrochloric acid in an organic solvent, and uniformly mixing to obtain a mixed solution of hydrogen chloride and the organic solvent;
5) Nitrosation reaction: dropwise adding the mixed solution of hydrogen chloride and an organic solvent prepared in the step 4) into the intermediate liquid B in the reaction kettle, and carrying out a chemical reaction on ethyl nitrite, phenol and hydrogen chloride in an inert gas atmosphere to generate p-benzoquinone monooxime, thus obtaining an intermediate liquid C;
6) Oximation reaction: adding hydroxylamine hydrochloride solid into the intermediate liquid C prepared in the step 5), and carrying out chemical reaction on p-benzoquinone monooxime and hydroxylamine hydrochloride in an inert gas atmosphere to generate p-benzoquinone dioxime, thus obtaining an intermediate liquid D;
7) Distilling the intermediate liquid D prepared in the step 6), condensing vapor generated by evaporation to obtain condensate, recovering the organic solvent from the condensate, and obtaining the residual liquid after evaporation;
8) Filtering the residual evaporation solution prepared in the step 7), and obtaining filter residue and filtrate after filtering;
9) And (3) sequentially washing, centrifugally dewatering and drying the filter residue prepared in the step 8) to obtain powdery benzoquinone dioxime.
In one embodiment of the application, in the step 1), the temperature of air in a kettle cavity in the reaction kettle is 0-5 ℃, the organic solvent is absolute ethyl alcohol, and the mass of ethyl nitrite to the mass of the organic solvent =1 (3-6).
In one embodiment of the application, in step 2), the amount of ethyl nitrite to phenol = (1-1.3) to 1.
In one embodiment of the present application, in step 3), the inert gas is nitrogen gas, so as to isolate air, inhibit disproportionation and decomposition of ethyl nitrite and oxidation of intermediate p-benzoquinone monooxime.
In one embodiment of the application, in the step 4), the mass of hydrogen chloride to the mass of phenol = (1-2) = (1-5), the organic solvent is absolute ethyl alcohol, and the mass of hydrogen chloride to the mass of organic solvent =1 (1-5).
In one embodiment of the application, in the step 5), when the temperature of the intermediate liquid B in the reaction kettle is reduced to 0 ℃, the mixed solution of the hydrogen chloride and the organic solvent prepared in the step 4) is dripped into the intermediate liquid B in the reaction kettle, and the dripping is completed within 1.5-3 h in the dripping process;
the reaction temperature of the nitrosation reaction is 0-8 ℃, and the reaction time of the nitrosation reaction is 0.5-2 h.
In one embodiment of the present application, in step 6), the mass of hydroxylamine hydrochloride = (1 to 1.3) the mass of phenol 1;
the reaction temperature of the oximation reaction is 60-75 ℃, and the reaction time of the oximation reaction is 2-4 h.
In one embodiment of the present application, the evaporation temperature during the distillation in step 7) is 70 ℃ to 85 ℃.
In one embodiment of the application, the filtrate obtained in step 8) and the waste water generated by washing in step 9) are mixed, then neutralized with an alkaline solution, and then evaporated and condensed to remove hydrogen chloride in the filtrate and the waste water, wherein the evaporation temperature is 90 ℃ to 105 ℃.
The application solves the theory of operation of waste water technical problem: the water solvent in the traditional synthesis process is replaced by absolute ethyl alcohol as the solvent, so that the introduction of water is avoided, and the output of waste water is reduced. The water contained in the synthesis reaction is only a small amount of water contained in concentrated hydrochloric acid, and the finally existing form is the waste water containing hydrogen chloride, and the hydrogen chloride can be removed in a filter residue mode through liquid alkali neutralization, distillation and condensation after ethanol is distilled and recovered.
The application solves the working principle of the technical problem of low raw material utilization rate: ethyl nitrite and phenol are subjected to nitrosation reaction under the action of an acidic reaction promoter to generate p-benzoquinone monooxime and ethanol, the p-benzoquinone monooxime is an intermediate for synthesizing p-benzoquinone dioxime, and the byproduct ethanol and an organic solvent ethanol can be recovered after distillation and condensation.
The application solves the working principle that the ethyl nitrite is easy to disproportionate and decompose when meeting air: in the reaction process, air and ethyl nitrite are completely isolated by using inert gas, so that a side reaction caused by the unstable property of the ethyl nitrite is avoided, and the reaction safety and the conversion rate are improved.
The application solves the working principle of the technical problem that p-benzoquinone monooxime is oxidized in air: the reaction process completely isolates the air from the intermediate p-benzoquinone monooxime by using inert gas, thereby avoiding the contact oxidation of the p-benzoquinone monooxime and the air to generate quinone substances and improving the yield and quality of the p-benzoquinone dioxime.
Methods and devices not described in detail in the present invention are all the prior art and are not described in detail.
For further understanding of the present invention, the following examples are provided to illustrate the preparation method of benzoquinone dioxime, and the scope of the present invention is not limited by the following examples.
Example 1
The preparation method of the p-benzoquinone dioxime comprises the following steps of:
1) Cooling the reaction kettle to 0-5 ℃, dissolving 39.38g of ethyl nitrite in 157.52g of absolute ethyl alcohol, uniformly mixing to obtain an intermediate liquid A, and slowly adding the intermediate liquid A into the cooled reaction kettle;
2) Adding 47g of phenol into the intermediate liquid A prepared in the step 1), and uniformly mixing to obtain an intermediate liquid B;
3) Vacuumizing the reaction kettle after the step 2) is finished, and then filling inert gas into the reaction kettle;
in the step 3), the inert gas is nitrogen and is used for isolating air and inhibiting the decomposition of ethyl nitrite;
4) Dissolving 48.02g of concentrated hydrochloric acid with the mass fraction of 36-38% in 72.03g of absolute ethyl alcohol, and uniformly mixing to obtain an ethanol solution of hydrogen chloride;
5) Nitrosation reaction: when the temperature of the intermediate liquid B in the reaction kettle is reduced to 0 ℃, dropwise adding the ethanol solution of hydrogen chloride prepared in the step 4) into the intermediate liquid B in the reaction kettle, and carrying out a chemical reaction on ethyl nitrite, phenol and hydrogen chloride in an inert gas atmosphere to generate p-benzoquinone monooxime, thus obtaining an intermediate liquid C;
in the step 5), finishing the dripping within 1.5h in the dripping process;
the reaction temperature of the nitrosation reaction is 0-8 ℃, and the reaction time of the nitrosation reaction is 0.5h;
6) Oximation reaction: adding 41.7g of hydroxylamine hydrochloride solid into the intermediate liquid C prepared in the step 5), and carrying out a chemical reaction on p-benzoquinone monooxime and hydroxylamine hydrochloride in an inert gas atmosphere to generate p-benzoquinone dioxime, thus obtaining an intermediate liquid D;
the reaction temperature of the oximation reaction is 70 ℃, and the reaction time of the oximation reaction is 2h;
7) Distilling the intermediate liquid D prepared in the step 6), condensing vapor generated by evaporation to obtain condensate, recovering the organic solvent from the condensate, and taking the residual liquid after evaporation as residual evaporation liquid;
in the step 7), the evaporation temperature in the distillation process is 75 ℃;
8) Filtering the residual evaporation solution prepared in the step 7), and obtaining filter residue and filtrate after filtering;
9) And (3) sequentially washing, centrifugally dewatering and drying the filter residue prepared in the step 8) to obtain powdery p-benzoquinone dioxime.
By detection and measurement, the mass of the p-benzoquinone dioxime prepared in example 1 is 60.06g, the yield is 86.97%, the appearance is light gray powder, the purity is 99.562wt%, and the DSC Peak point is 250.18 ℃.
Example 2
The preparation method of the p-benzoquinone dioxime comprises the following steps of:
1) Cooling the reaction kettle to 0-5 ℃, dissolving 39.38g of ethyl nitrite in 157.52g of absolute ethyl alcohol, uniformly mixing to obtain an intermediate liquid A, and slowly adding the intermediate liquid A into the cooled reaction kettle;
2) Adding 47g of phenol into the intermediate liquid A prepared in the step 1), and uniformly mixing to obtain an intermediate liquid B;
3) Vacuumizing the reaction kettle after the step 2) is finished, and then filling inert gas into the reaction kettle;
in the step 3), the inert gas is nitrogen and is used for isolating air and inhibiting the decomposition of ethyl nitrite;
4) Dissolving 96.05g of concentrated hydrochloric acid with the mass fraction of 36-38% in 144.08g of absolute ethyl alcohol, and uniformly mixing to obtain an ethanol solution of hydrogen chloride;
5) Nitrosation reaction: when the temperature of the intermediate liquid B in the reaction kettle is reduced to 0 ℃, dropwise adding the ethanol solution of hydrogen chloride prepared in the step 4) into the intermediate liquid B in the reaction kettle, carrying out chemical reaction on ethyl nitrite, phenol and hydrogen chloride in an inert gas atmosphere to generate benzoquinone monooxime, and obtaining an intermediate liquid C after the reaction;
in the step 5), finishing the dripping within 1.5h in the dripping process;
the reaction temperature of the nitrosation reaction is 0-8 ℃, and the reaction time of the nitrosation reaction is 0.5h;
6) Oximation reaction: adding 41.7g of hydroxylamine hydrochloride solid into the intermediate liquid C prepared in the step 5), and carrying out a chemical reaction on p-benzoquinone monooxime and hydroxylamine hydrochloride in an inert gas atmosphere to generate p-benzoquinone dioxime to obtain an intermediate liquid D;
the reaction temperature of the oximation reaction is 70 ℃, and the reaction time of the oximation reaction is 2h;
7) Distilling the intermediate liquid D prepared in the step 6), condensing vapor generated by evaporation to obtain condensate, recovering the organic solvent from the condensate, and obtaining the residual liquid after evaporation;
in the step 7), the evaporation temperature in the distillation process is 75 ℃;
8) Filtering the residual evaporation solution prepared in the step 7), and obtaining filter residue and filtrate after filtering;
9) And (3) sequentially washing, centrifugally dewatering and drying the filter residue prepared in the step 8) to obtain powdery benzoquinone dioxime.
Through detection and measurement, the quality of the p-benzoquinone dioxime prepared in example 2 is 61.24g, the yield is 88.68%, the appearance is light gray powder, the purity is 99.642wt%, and the DSC Peak point is 251.66 ℃.
Example 3
A preparation method of p-benzoquinone dioxime comprises the following steps of:
1) Cooling the reaction kettle to 0-5 ℃, dissolving 39.38g of ethyl nitrite in 157.52g of absolute ethyl alcohol, uniformly mixing to obtain an intermediate liquid A, and slowly adding the intermediate liquid A into the cooled reaction kettle;
2) Adding 47g of phenol into the intermediate liquid A prepared in the step 1), and uniformly mixing to obtain an intermediate liquid B;
3) Vacuumizing the reaction kettle after the step 2) is finished, and then filling inert gas into the reaction kettle;
in the step 3), the inert gas is nitrogen and is used for isolating air and inhibiting the decomposition of ethyl nitrite;
4) Dissolving 96.05g of concentrated hydrochloric acid with the mass fraction of 36-38% in 288.15g of absolute ethanol, and uniformly mixing to obtain an ethanol solution of hydrogen chloride;
5) Nitrosation reaction: when the temperature of the intermediate liquid B in the reaction kettle is reduced to 0 ℃, dropwise adding the ethanol solution of hydrogen chloride prepared in the step 4) into the intermediate liquid B in the reaction kettle, and carrying out a chemical reaction on ethyl nitrite, phenol and hydrogen chloride in an inert gas atmosphere to generate p-benzoquinone monooxime, thus obtaining an intermediate liquid C;
in the step 5), finishing the dripping within 2h in the dripping process;
the reaction temperature of the nitrosation reaction is 0-8 ℃, and the reaction time of the nitrosation reaction is 0.5h;
6) Oximation reaction: adding 41.7g of hydroxylamine hydrochloride solid into the intermediate liquid C prepared in the step 5), and carrying out a chemical reaction on p-benzoquinone monooxime and hydroxylamine hydrochloride in an inert gas atmosphere to generate p-benzoquinone dioxime, thus obtaining an intermediate liquid D;
the reaction temperature of the oximation reaction is 70 ℃, and the reaction time of the oximation reaction is 2h;
7) Distilling the intermediate liquid D prepared in the step 6), condensing vapor generated by evaporation to obtain condensate, recovering the organic solvent from the condensate, and obtaining the residual liquid after evaporation;
in the step 7), the evaporation temperature in the distillation process is 75 ℃;
8) Filtering the residual evaporation solution prepared in the step 7), and obtaining filter residue and filtrate after filtering;
9) And (3) sequentially washing, centrifugally dewatering and drying the filter residue prepared in the step 8) to obtain powdery benzoquinone dioxime.
By detection and measurement, the quality of the p-benzoquinone dioxime prepared in example 3 is 62.74g, the yield is 90.85%, the appearance is light gray powder, the purity is 99.750wt%, and the DSC Peak point is 254.39 ℃.
The above description of the embodiments is only intended to facilitate the understanding of the method of the invention and its core idea. It should be noted that, for those skilled in the art, it is possible to make various improvements and modifications to the present invention without departing from the principle of the present invention, and those improvements and modifications also fall within the scope of the claims of the present invention.
Claims (8)
1. The preparation method of p-benzoquinone dioxime is characterized by comprising the following steps of:
1) Dissolving ethyl nitrite in an organic solvent in a reaction kettle, and uniformly mixing to obtain an intermediate liquid A;
2) Adding phenol into the intermediate liquid A prepared in the step 1), and uniformly mixing to obtain an intermediate liquid B;
3) Vacuumizing the reaction kettle after the step 2) is finished, and then filling inert gas into the reaction kettle;
4) Dissolving concentrated hydrochloric acid in an organic solvent, and uniformly mixing to obtain a mixed solution of hydrogen chloride and the organic solvent;
5) Nitrosation reaction: dropwise adding the mixed solution of hydrogen chloride and an organic solvent prepared in the step 4) into the intermediate liquid B in the reaction kettle, and carrying out a chemical reaction on ethyl nitrite, phenol and hydrogen chloride in an inert gas atmosphere to generate p-benzoquinone monooxime, thus obtaining an intermediate liquid C;
6) Oximation reaction: adding hydroxylamine hydrochloride solid into the intermediate liquid C prepared in the step 5), and carrying out chemical reaction on p-benzoquinone monooxime and hydroxylamine hydrochloride in an inert gas atmosphere to generate p-benzoquinone dioxime, thus obtaining an intermediate liquid D;
7) Distilling the intermediate liquid D prepared in the step 6), condensing vapor generated by evaporation to obtain condensate, recovering the organic solvent from the condensate, and taking the residual liquid after evaporation as residual evaporation liquid;
8) Filtering the residual evaporation solution prepared in the step 7), and obtaining filter residue and filtrate after filtering;
9) Washing the filter residue prepared in the step 8) with water, centrifugally dewatering, drying, and drying to obtain powdery benzoquinone dioxime;
in the step 1), the temperature of air in a kettle cavity in the reaction kettle is 0-5 ℃, the organic solvent is absolute ethyl alcohol, and the mass of ethyl nitrite is equal to that of the organic solvent =1 (3-6).
2. The method for producing p-benzoquinone dioxime according to claim 1, wherein in step 2), the amount of ethyl nitrite to phenol is = (1 to 1.3) to 1.
3. The method as claimed in claim 1, wherein the inert gas is nitrogen in the step 3) for preventing air and inhibiting disproportionation and decomposition of ethyl nitrite and oxidation of intermediate p-benzoquinone monooxime.
4. The method for producing p-benzoquinone dioxime according to claim 1, wherein in step 4), the mass of hydrogen chloride to the mass of phenol = (1 to 2): 1, the organic solvent is absolute ethanol, and the mass of hydrogen chloride to the mass of organic solvent =1 (1 to 5).
5. The method for preparing p-benzoquinone dioxime according to claim 1, wherein in step 5), when the temperature of the intermediate liquid B in the reaction kettle is reduced to 0 ℃, the mixed solution of hydrogen chloride and the organic solvent prepared in step 4) is added dropwise into the intermediate liquid B in the reaction kettle, and the dropwise addition is completed within 1.5 to 3 hours;
the reaction temperature of the nitrosation reaction is 0-8 ℃, and the reaction time of the nitrosation reaction is 0.5-2 h.
6. The method according to claim 1, wherein in step 6), the mass of hydroxylamine hydrochloride is 1 to 1;
the reaction temperature of the oximation reaction is 60-75 ℃, and the reaction time of the oximation reaction is 2-4 h.
7. The method of claim 1, wherein the evaporation temperature of the distillation process in the step 7) is 70 to 85 ℃.
8. The method of claim 1, wherein the filtrate obtained in the step 8) is mixed with the waste water from the washing in the step 9), and then neutralized with an alkali solution, and then evaporated and condensed to remove hydrogen chloride from the filtrate and the waste water, wherein the evaporation temperature is 90 ℃ to 105 ℃.
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