CN111018654B - Compound polymerization inhibitor for styrene rectification - Google Patents
Compound polymerization inhibitor for styrene rectification Download PDFInfo
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- CN111018654B CN111018654B CN201911113119.9A CN201911113119A CN111018654B CN 111018654 B CN111018654 B CN 111018654B CN 201911113119 A CN201911113119 A CN 201911113119A CN 111018654 B CN111018654 B CN 111018654B
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- polymerization inhibitor
- styrene
- compound
- nitroxide radical
- nitroxide
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- PPBRXRYQALVLMV-UHFFFAOYSA-N Styrene Chemical compound C=CC1=CC=CC=C1 PPBRXRYQALVLMV-UHFFFAOYSA-N 0.000 title claims abstract description 75
- 238000006116 polymerization reaction Methods 0.000 title claims abstract description 56
- 239000003112 inhibitor Substances 0.000 title claims abstract description 48
- 150000001875 compounds Chemical class 0.000 title claims abstract description 13
- -1 nitroxide free radical compound Chemical class 0.000 claims abstract description 23
- 239000002904 solvent Substances 0.000 claims abstract description 5
- YNQLUTRBYVCPMQ-UHFFFAOYSA-N Ethylbenzene Chemical group CCC1=CC=CC=C1 YNQLUTRBYVCPMQ-UHFFFAOYSA-N 0.000 claims description 16
- 238000000034 method Methods 0.000 claims description 9
- 150000003254 radicals Chemical class 0.000 claims description 6
- UWDMKTDPDJCJOP-UHFFFAOYSA-N 4-hydroxy-2,2,6,6-tetramethylpiperidin-1-ium-4-carboxylate Chemical compound CC1(C)CC(O)(C(O)=O)CC(C)(C)N1 UWDMKTDPDJCJOP-UHFFFAOYSA-N 0.000 claims description 4
- 229910052736 halogen Inorganic materials 0.000 claims description 3
- 150000002367 halogens Chemical group 0.000 claims description 3
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 claims description 2
- WKBOTKDWSSQWDR-UHFFFAOYSA-N Bromine atom Chemical compound [Br] WKBOTKDWSSQWDR-UHFFFAOYSA-N 0.000 claims description 2
- ZAMOUSCENKQFHK-UHFFFAOYSA-N Chlorine atom Chemical compound [Cl] ZAMOUSCENKQFHK-UHFFFAOYSA-N 0.000 claims description 2
- PXGOKWXKJXAPGV-UHFFFAOYSA-N Fluorine Chemical compound FF PXGOKWXKJXAPGV-UHFFFAOYSA-N 0.000 claims description 2
- GDTBXPJZTBHREO-UHFFFAOYSA-N bromine Substances BrBr GDTBXPJZTBHREO-UHFFFAOYSA-N 0.000 claims description 2
- 229910052794 bromium Inorganic materials 0.000 claims description 2
- 229910052801 chlorine Inorganic materials 0.000 claims description 2
- 239000000460 chlorine Substances 0.000 claims description 2
- 229910052731 fluorine Inorganic materials 0.000 claims description 2
- 239000011737 fluorine Substances 0.000 claims description 2
- 229910052740 iodine Inorganic materials 0.000 claims description 2
- 239000011630 iodine Substances 0.000 claims description 2
- 230000000694 effects Effects 0.000 abstract description 5
- 230000005764 inhibitory process Effects 0.000 abstract description 3
- 238000004519 manufacturing process Methods 0.000 abstract description 2
- 230000002195 synergetic effect Effects 0.000 abstract description 2
- 230000001988 toxicity Effects 0.000 abstract 1
- 231100000419 toxicity Toxicity 0.000 abstract 1
- 229920000642 polymer Polymers 0.000 description 8
- OWZPCEFYPSAJFR-UHFFFAOYSA-N 2-(butan-2-yl)-4,6-dinitrophenol Chemical compound CCC(C)C1=CC([N+]([O-])=O)=CC([N+]([O-])=O)=C1O OWZPCEFYPSAJFR-UHFFFAOYSA-N 0.000 description 6
- 230000035484 reaction time Effects 0.000 description 5
- 239000000243 solution Substances 0.000 description 5
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 description 3
- 230000008901 benefit Effects 0.000 description 3
- 230000000052 comparative effect Effects 0.000 description 3
- 231100000053 low toxicity Toxicity 0.000 description 3
- RMVRSNDYEFQCLF-UHFFFAOYSA-N thiophenol Chemical compound SC1=CC=CC=C1 RMVRSNDYEFQCLF-UHFFFAOYSA-N 0.000 description 3
- 238000006356 dehydrogenation reaction Methods 0.000 description 2
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 description 2
- AZQWKYJCGOJGHM-UHFFFAOYSA-N 1,4-benzoquinone Chemical compound O=C1C=CC(=O)C=C1 AZQWKYJCGOJGHM-UHFFFAOYSA-N 0.000 description 1
- WJFKNYWRSNBZNX-UHFFFAOYSA-N 10H-phenothiazine Chemical compound C1=CC=C2NC3=CC=CC=C3SC2=C1 WJFKNYWRSNBZNX-UHFFFAOYSA-N 0.000 description 1
- UFBJCMHMOXMLKC-UHFFFAOYSA-N 2,4-dinitrophenol Chemical compound OC1=CC=C([N+]([O-])=O)C=C1[N+]([O-])=O UFBJCMHMOXMLKC-UHFFFAOYSA-N 0.000 description 1
- HOYRZHJJAHRMLL-UHFFFAOYSA-N 2,6-dinitro-p-cresol Chemical compound CC1=CC([N+]([O-])=O)=C(O)C([N+]([O-])=O)=C1 HOYRZHJJAHRMLL-UHFFFAOYSA-N 0.000 description 1
- JIGUICYYOYEXFS-UHFFFAOYSA-N 3-tert-butylbenzene-1,2-diol Chemical compound CC(C)(C)C1=CC=CC(O)=C1O JIGUICYYOYEXFS-UHFFFAOYSA-N 0.000 description 1
- AVXURJPOCDRRFD-UHFFFAOYSA-N Hydroxylamine Chemical compound ON AVXURJPOCDRRFD-UHFFFAOYSA-N 0.000 description 1
- PMZURENOXWZQFD-UHFFFAOYSA-L Sodium Sulfate Chemical compound [Na+].[Na+].[O-]S([O-])(=O)=O PMZURENOXWZQFD-UHFFFAOYSA-L 0.000 description 1
- 239000002253 acid Substances 0.000 description 1
- 239000000654 additive Substances 0.000 description 1
- 239000003513 alkali Substances 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000003054 catalyst Substances 0.000 description 1
- 230000003197 catalytic effect Effects 0.000 description 1
- 238000006243 chemical reaction Methods 0.000 description 1
- 239000012295 chemical reaction liquid Substances 0.000 description 1
- 239000002274 desiccant Substances 0.000 description 1
- 238000010494 dissociation reaction Methods 0.000 description 1
- 230000005593 dissociations Effects 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- 239000012153 distilled water Substances 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 238000011049 filling Methods 0.000 description 1
- 238000001914 filtration Methods 0.000 description 1
- 238000004817 gas chromatography Methods 0.000 description 1
- 125000001475 halogen functional group Chemical group 0.000 description 1
- 231100000086 high toxicity Toxicity 0.000 description 1
- 125000004435 hydrogen atom Chemical group [H]* 0.000 description 1
- 150000002443 hydroxylamines Chemical class 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000010813 internal standard method Methods 0.000 description 1
- 239000011259 mixed solution Substances 0.000 description 1
- 238000002156 mixing Methods 0.000 description 1
- 239000000203 mixture Substances 0.000 description 1
- 239000000178 monomer Substances 0.000 description 1
- 230000007935 neutral effect Effects 0.000 description 1
- ISWSIDIOOBJBQZ-UHFFFAOYSA-N phenol group Chemical group C1(=CC=CC=C1)O ISWSIDIOOBJBQZ-UHFFFAOYSA-N 0.000 description 1
- 150000002989 phenols Chemical class 0.000 description 1
- 229950000688 phenothiazine Drugs 0.000 description 1
- 238000000746 purification Methods 0.000 description 1
- 150000004053 quinones Chemical class 0.000 description 1
- 239000002994 raw material Substances 0.000 description 1
- 238000007670 refining Methods 0.000 description 1
- 238000000926 separation method Methods 0.000 description 1
- 239000000126 substance Substances 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 238000010998 test method Methods 0.000 description 1
- 238000012719 thermal polymerization Methods 0.000 description 1
- 125000002023 trifluoromethyl group Chemical group FC(F)(F)* 0.000 description 1
- 238000005303 weighing Methods 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/20—Use of additives, e.g. for stabilisation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C7/00—Purification; Separation; Use of additives
- C07C7/04—Purification; Separation; Use of additives by distillation
-
- Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
- Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
- Y02P—CLIMATE CHANGE MITIGATION TECHNOLOGIES IN THE PRODUCTION OR PROCESSING OF GOODS
- Y02P20/00—Technologies relating to chemical industry
- Y02P20/10—Process efficiency
Landscapes
- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Engineering & Computer Science (AREA)
- Analytical Chemistry (AREA)
- Oil, Petroleum & Natural Gas (AREA)
- Water Supply & Treatment (AREA)
- Polymerisation Methods In General (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention relates to a compound polymerization inhibitor for styrene rectification. The compound polymerization inhibitor consists of a nitroxide free radical compound, 2, 4-bistrifluoromethyl thiophenol halide and a solvent. The compound polymerization inhibitor remarkably improves the polymerization inhibition effect by utilizing the synergistic effect among the components, reduces the tar emission of a styrene device, improves the production capacity of the styrene rectification device, reduces the toxicity of the polymerization inhibitor and is environment-friendly.
Description
Technical Field
The invention belongs to the field of chemical additives, and relates to a compound polymerization inhibitor suitable for a styrene rectification process.
Background
Styrene is a basic product of petrochemical industry and is also an important raw material for synthesizing polymers. Styrene has the property of thermal polymerization, i.e., the temperature initiates its polymerization, and the higher the temperature, the faster the polymerization rate. In the industry, styrene is produced mainly by ethylbenzene gas-phase catalytic dehydrogenation, and the mixed solution after ethylbenzene dehydrogenation is sent to a rectifying tower for rectification separation, so that the temperature of the process is higher, and the styrene loss is very serious. The polymer produced also blocks the equipment and pipelines of the next process, which affects the normal operation of industrial production, and therefore, polymerization inhibitors must be added during the rectification process.
Since the 70 s of the 20 th century, styrene rectification polymerization inhibitors have undergone several updates. The first polymerization inhibitors were single-component polymerization inhibitors, mainly phenols (such as dinitrophenol) and quinones (such as benzoquinone). In the 80 s of the 20 th century, in order to improve the drawbacks of the first type of polymerization inhibitors, such as high toxicity, serious environmental pollution, etc., other groups have been introduced into the structure of the first type of polymerization inhibitors, and the second type of polymerization inhibitors, such as 2-sec-butyl-4, 6-Dinitrophenol (DNBP), has emerged. The second type of polymerization inhibitor also includes the piperidine nitroxide inhibitors and hydroxylamine derivatives which have been discovered later. In the 90 s of the 20 th century, some novel efficient and low-toxicity polymerization inhibitors are tried on a styrene device, patent US 4466904 discloses a polymerization inhibitor for refining styrene compounded by 2, 6-dinitro-p-cresol, tert-butylcatechol and phenothiazine, and patent EP 240297 discloses a three-component compounded styrene rectification polymerization inhibitor mainly comprising hydroxylamine, and the compounded polymerization inhibitor is called a third-generation polymerization inhibitor. However, the compound polymerization inhibitor has the advantages of higher dosage, low economical efficiency, complex composition and difficult grasp of the proportions of the components, so that the novel styrene polymerization inhibitor with high efficiency, stability and low toxicity is also required to be developed, the loss of monomers is reduced as much as possible, and the production efficiency is improved.
Disclosure of Invention
The invention aims to solve the technical problem of reducing the loss caused by polymerization in the styrene rectification process and provides an efficient compound polymerization inhibitor for the styrene rectification process. Compared with the prior art, the polymerization inhibitor has the advantages of low toxicity and low consumption, can effectively prolong the operation time of a styrene device, reduces the operation cost of the device, and has good economic benefit and popularization prospect.
In order to solve the technical problems, the invention provides a compound polymerization inhibitor for styrene rectification, which comprises the following components in percentage by mass:
a) Contains 5 to 40 mass percent of nitroxide free radical compounds;
b) Contains 1 to 15 mass percent of 2, 4-difluoro methyl thiophenol halide, and has one or more of the following structural formulas:
wherein X is halogen, preferably fluorine, chlorine, bromine or iodine;
c) The rest is solvent, wherein the solvent is ethylbenzene or styrene;
wherein the nitroxide radical compound is N, N-di-tert-butyl nitroxide radical, tert-amyl tert-butyl nitroxide radical, 2, 6-tetramethyl piperidine nitroxide radical 4-hydroxy-2, 6-tetramethylpiperidine nitroxide radical, 4-carbonyl-2, 6-tetramethylpiperidine nitroxide radical 4-hydroxy-2, 6-tetramethylpiperidine nitroxide radical 4-carbonyl-2, 6-tetramethyl piperidine nitroxide radical.
The preferable percentage of the nitrogen-oxygen free radical compound in the polymerization inhibitor product is 10-30%; the preferred percentage of 2, 4-bistrifluoromethyl thiophenol halide is 5% to 10%.
The amount of the polymerization inhibitor added to styrene is preferably in the range of 100 to 1500ppm, more preferably in the range of 200 to 1000ppm.
The compound polymerization inhibitor for styrene rectification is characterized in that the 2, 4-bistrifluoromethyl thiophenol halide has two trifluoromethyl and halogen functional groups, and has strong electron-withdrawing effect, so that the activity of hydrogen atoms on thiophenol is greatly enhanced, the acid dissociation constant (pKa) is smaller than that of 2-sec-butyl-4, 6-Dinitrophenol (DNBP), the compound polymerization inhibitor is easier to combine with free radicals in a system, and the polymerization inhibition effect is better.
The polymerization inhibitor product of the invention is characterized in that: the 2, 4-difluoro methyl thiophenol halide can obviously reduce the rate of styrene polymerization in a styrene rectification system, the nitroxide free radical compound can be quickly and effectively combined with free radicals in the styrene system to terminate the polymerization reaction, and the two compounds can generate a synergistic effect in the styrene system, so that the catalyst has an excellent polymerization inhibition effect. Meanwhile, compared with the traditional polymerization inhibitor product, the polymerization inhibitor product has the characteristics of two polymerization inhibitors of slow resistance and true resistance in industrial application, and only one filling point is needed, thereby being beneficial to industrial application and popularization.
Detailed Description
For a better understanding of the present invention, the following examples are further illustrated, but are not limited to the following examples.
Purification and treatment of styrene
A certain amount of styrene is taken in a separating funnel, repeatedly washed by 5% sodium hydroxide solution (reacted with phenolic polymerization inhibitor in the styrene), and the styrene solution washed by alkali solution is colorless or slightly yellowish during the process of shaking (gassing |). The solution was washed with distilled water until the aqueous layer was neutral (pH test), and after separating the water layer, anhydrous sodium sulfate was added to dry and left to stand until it became clear. The drying agent was removed by filtration, and then placed in a Kirschner flask for distillation under reduced pressure (CaH was added during the process) 2 ) Fractions were collected at 44-45 ℃/2666.44Pa (20 mmHg) or 59-60 ℃/5332.8Pa (40 mmHg). Pure styrene monomer is obtained.
Polymerization experimental condition and test method
And (3) weighing 50g of purified styrene by using a clean colorimetric tube with a plug, accurately injecting a certain amount of polymerization inhibitor solution by using a microsyringe, fully mixing, placing in an oil bath at 120 ℃ and starting timing, taking a proper amount of reaction liquid after a period of reaction, measuring the styrene content in the system by using a gas chromatography internal standard method, and further calculating the generation amount of the polymer.
Example 1
The components of the polymerization inhibitor are as follows:
4-carbonyl-2, 6-tetramethylpiperidine nitroxide radical: 10 percent of
3-chloro-2, 4-bistrifluoromethyl thiophenol: 1%
Ethylbenzene: 89%
Example two
The components of the polymerization inhibitor are as follows:
4-carbonyl-2, 6-tetramethylpiperidine nitroxide radical: 20 percent of
3-chloro-2, 4-bistrifluoromethyl thiophenol: 10 percent of
Ethylbenzene: 70 percent of
Example III
The components of the polymerization inhibitor are as follows:
4-carbonyl-2, 6-tetramethylpiperidine nitroxide radical: 30%
3-chloro-2, 4-bistrifluoromethyl thiophenol: 15%
Ethylbenzene: 55%
Comparative examples:
4-carbonyl-2, 6-tetramethylpiperidine nitroxide radical: 20 percent of
2-sec-butyl-4, 6-Dinitrophenol (DNBP): 10 percent of
Ethylbenzene: 70 percent of
TABLE 1 Polymer content after a reaction time of 20min with 300ppm
TABLE 2 Polymer content after 40min of reaction time with 300ppm of the addition
| Polymerization inhibitor addition amount | Reaction time | Polymer content | |
| Example 1 | 300 | 40 | 0.20％ |
| Example 2 | 300 | 40 | 0.12％ |
| Example 3 | 300 | 40 | 0.12％ |
| Comparative examples | 300 | 40 | 0.25％ |
TABLE 3 Polymer content after 40min of reaction time with different addition amounts
| Polymerization inhibitor addition amount | Reaction time | Polymer content | |
| Example 1 | 300 | 40 | 0.20％ |
| Example 2 | 300 | 40 | 0.12％ |
| Example 3 | 300 | 40 | 0.12％ |
| Comparative examples | 500 | 40 | 0.19％ |
Claims (6)
1. A compound polymerization inhibitor for styrene rectification is characterized in that: the components and the mass percentages of the components are as follows:
a) 5% -40% of nitroxide free radical compound;
b) 1 to 15 percent of 2, 4-bistrifluoromethyl thiophenol halide, which has one or more of the following structural formulas:
wherein X is halogen;
c) The rest is solvent, and the solvent is ethylbenzene or styrene;
wherein the nitroxide radical compound is N, N-di-tert-butyl nitroxide radical, tert-amyl tert-butyl nitroxide radical, 2, 6-tetramethyl piperidine nitroxide radical 4-hydroxy-2, 6-tetramethylpiperidine nitroxide radical, 4-carbonyl-2, 6-tetramethylpiperidine nitroxide radical 4-hydroxy-2, 6-tetramethylpiperidine nitroxide radical 4-carbonyl-2, 6-tetramethyl piperidine nitroxide radical.
2. The polymerization inhibitor according to claim 1, wherein the mass percentage of the nitroxide compound is 10-30%.
3. The polymerization inhibitor according to claim 1, wherein the mass percentage of the 2, 4-bistrifluoromethyl thiophenol halide is 5% to 10%.
4. The polymerization inhibitor according to claim 1, wherein the halogen is fluorine, chlorine, bromine or iodine.
5. The polymerization inhibitor for styrene rectification as defined in claim 1, wherein said polymerization inhibitor is added to styrene in an amount of 100 to 1500ppm.
6. The process according to claim 5, wherein the polymerization inhibitor is added to styrene in an amount of 200 to 1000ppm.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911113119.9A CN111018654B (en) | 2019-11-14 | 2019-11-14 | Compound polymerization inhibitor for styrene rectification |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201911113119.9A CN111018654B (en) | 2019-11-14 | 2019-11-14 | Compound polymerization inhibitor for styrene rectification |
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| Publication Number | Publication Date |
|---|---|
| CN111018654A CN111018654A (en) | 2020-04-17 |
| CN111018654B true CN111018654B (en) | 2023-05-09 |
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Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5728872A (en) * | 1994-06-27 | 1998-03-17 | Lutz Riemenschneider | Stabilized acrylic acid compositions |
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2019
- 2019-11-14 CN CN201911113119.9A patent/CN111018654B/en active Active
Patent Citations (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5728872A (en) * | 1994-06-27 | 1998-03-17 | Lutz Riemenschneider | Stabilized acrylic acid compositions |
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| CN111018654A (en) | 2020-04-17 |
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