CN115594566A - Synthesis method of 2, 5-dimethyl-2, 5-hexanediol - Google Patents
Synthesis method of 2, 5-dimethyl-2, 5-hexanediol Download PDFInfo
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- CN115594566A CN115594566A CN202211159449.3A CN202211159449A CN115594566A CN 115594566 A CN115594566 A CN 115594566A CN 202211159449 A CN202211159449 A CN 202211159449A CN 115594566 A CN115594566 A CN 115594566A
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- dimethylhexane
- hexanediol
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- ZWNMRZQYWRLGMM-UHFFFAOYSA-N 2,5-dimethylhexane-2,5-diol Chemical compound CC(C)(O)CCC(C)(C)O ZWNMRZQYWRLGMM-UHFFFAOYSA-N 0.000 title claims abstract description 50
- 238000001308 synthesis method Methods 0.000 title description 5
- 238000006243 chemical reaction Methods 0.000 claims abstract description 96
- UWNADWZGEHDQAB-UHFFFAOYSA-N 2,5-dimethylhexane Chemical compound CC(C)CCC(C)C UWNADWZGEHDQAB-UHFFFAOYSA-N 0.000 claims abstract description 84
- 238000000034 method Methods 0.000 claims abstract description 47
- QRMPKOFEUHIBNM-UHFFFAOYSA-N p-dimethylcyclohexane Natural products CC1CCC(C)CC1 QRMPKOFEUHIBNM-UHFFFAOYSA-N 0.000 claims abstract description 42
- 238000005406 washing Methods 0.000 claims abstract description 42
- 239000007789 gas Substances 0.000 claims abstract description 22
- 238000003756 stirring Methods 0.000 claims abstract description 20
- QVGXLLKOCUKJST-UHFFFAOYSA-N atomic oxygen Chemical compound [O] QVGXLLKOCUKJST-UHFFFAOYSA-N 0.000 claims abstract description 19
- 239000012074 organic phase Substances 0.000 claims abstract description 19
- 239000001301 oxygen Substances 0.000 claims abstract description 19
- 229910052760 oxygen Inorganic materials 0.000 claims abstract description 19
- 239000003054 catalyst Substances 0.000 claims abstract description 16
- 230000002194 synthesizing effect Effects 0.000 claims abstract description 15
- 239000003999 initiator Substances 0.000 claims abstract description 14
- 238000007789 sealing Methods 0.000 claims abstract description 12
- 238000001035 drying Methods 0.000 claims abstract description 11
- 238000010438 heat treatment Methods 0.000 claims abstract description 10
- 239000003513 alkali Substances 0.000 claims abstract description 8
- 239000002351 wastewater Substances 0.000 claims abstract description 8
- 239000012295 chemical reaction liquid Substances 0.000 claims abstract description 6
- HEMHJVSKTPXQMS-UHFFFAOYSA-M Sodium hydroxide Chemical compound [OH-].[Na+] HEMHJVSKTPXQMS-UHFFFAOYSA-M 0.000 claims description 30
- KWYUFKZDYYNOTN-UHFFFAOYSA-M Potassium hydroxide Chemical compound [OH-].[K+] KWYUFKZDYYNOTN-UHFFFAOYSA-M 0.000 claims description 28
- 239000000243 solution Substances 0.000 claims description 23
- 239000012452 mother liquor Substances 0.000 claims description 21
- 239000007787 solid Substances 0.000 claims description 14
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Chemical compound O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims description 14
- 238000002425 crystallisation Methods 0.000 claims description 12
- 239000002994 raw material Substances 0.000 claims description 11
- 230000008025 crystallization Effects 0.000 claims description 10
- 239000011259 mixed solution Substances 0.000 claims description 9
- GEMHFKXPOCTAIP-UHFFFAOYSA-N n,n-dimethyl-n'-phenylcarbamimidoyl chloride Chemical compound CN(C)C(Cl)=NC1=CC=CC=C1 GEMHFKXPOCTAIP-UHFFFAOYSA-N 0.000 claims description 9
- FRIBMENBGGCKPD-UHFFFAOYSA-N 3-(2,3-dimethoxyphenyl)prop-2-enal Chemical compound COC1=CC=CC(C=CC=O)=C1OC FRIBMENBGGCKPD-UHFFFAOYSA-N 0.000 claims description 8
- 239000007864 aqueous solution Substances 0.000 claims description 8
- 238000001816 cooling Methods 0.000 claims description 8
- 239000008367 deionised water Substances 0.000 claims description 7
- 229910021641 deionized water Inorganic materials 0.000 claims description 7
- 239000007788 liquid Substances 0.000 claims description 6
- 239000000203 mixture Substances 0.000 claims description 6
- 239000010413 mother solution Substances 0.000 claims description 6
- 238000003786 synthesis reaction Methods 0.000 claims description 6
- 239000002585 base Substances 0.000 claims description 5
- 230000015572 biosynthetic process Effects 0.000 claims description 5
- 238000007605 air drying Methods 0.000 claims description 4
- 238000000926 separation method Methods 0.000 claims description 4
- CIHOLLKRGTVIJN-UHFFFAOYSA-N tert‐butyl hydroperoxide Chemical compound CC(C)(C)OO CIHOLLKRGTVIJN-UHFFFAOYSA-N 0.000 claims description 4
- 229940011182 cobalt acetate Drugs 0.000 claims description 2
- AMFIJXSMYBKJQV-UHFFFAOYSA-L cobalt(2+);octadecanoate Chemical compound [Co+2].CCCCCCCCCCCCCCCCCC([O-])=O.CCCCCCCCCCCCCCCCCC([O-])=O AMFIJXSMYBKJQV-UHFFFAOYSA-L 0.000 claims description 2
- QAHREYKOYSIQPH-UHFFFAOYSA-L cobalt(II) acetate Chemical compound [Co+2].CC([O-])=O.CC([O-])=O QAHREYKOYSIQPH-UHFFFAOYSA-L 0.000 claims description 2
- SPTHWAJJMLCAQF-UHFFFAOYSA-M ctk4f8481 Chemical compound [O-]O.CC(C)C1=CC=CC=C1C(C)C SPTHWAJJMLCAQF-UHFFFAOYSA-M 0.000 claims description 2
- 238000010992 reflux Methods 0.000 claims description 2
- 238000010583 slow cooling Methods 0.000 claims description 2
- 239000007858 starting material Substances 0.000 claims description 2
- 238000005984 hydrogenation reaction Methods 0.000 abstract description 6
- 238000004519 manufacturing process Methods 0.000 abstract description 3
- 230000003647 oxidation Effects 0.000 abstract description 3
- 238000007254 oxidation reaction Methods 0.000 abstract description 3
- 238000010189 synthetic method Methods 0.000 abstract description 2
- 239000000047 product Substances 0.000 description 25
- CSCPPACGZOOCGX-UHFFFAOYSA-N Acetone Chemical compound CC(C)=O CSCPPACGZOOCGX-UHFFFAOYSA-N 0.000 description 8
- 230000000052 comparative effect Effects 0.000 description 5
- ZCYVEMRRCGMTRW-UHFFFAOYSA-N 7553-56-2 Chemical compound [I] ZCYVEMRRCGMTRW-UHFFFAOYSA-N 0.000 description 4
- CLBRCZAHAHECKY-UHFFFAOYSA-N [Co].[Pt] Chemical compound [Co].[Pt] CLBRCZAHAHECKY-UHFFFAOYSA-N 0.000 description 4
- 150000002083 enediols Chemical class 0.000 description 4
- KXUSQYGLNZFMTE-UHFFFAOYSA-N hex-2-yne-1,1-diol Chemical compound CCCC#CC(O)O KXUSQYGLNZFMTE-UHFFFAOYSA-N 0.000 description 4
- 239000011630 iodine Substances 0.000 description 4
- 229910052740 iodine Inorganic materials 0.000 description 4
- 238000002844 melting Methods 0.000 description 4
- 230000008018 melting Effects 0.000 description 4
- 229930195735 unsaturated hydrocarbon Natural products 0.000 description 4
- HSFWRNGVRCDJHI-UHFFFAOYSA-N alpha-acetylene Natural products C#C HSFWRNGVRCDJHI-UHFFFAOYSA-N 0.000 description 3
- 125000002534 ethynyl group Chemical group [H]C#C* 0.000 description 3
- 239000012535 impurity Substances 0.000 description 3
- 239000000463 material Substances 0.000 description 3
- -1 polyethylene Polymers 0.000 description 3
- CTQNGGLPUBDAKN-UHFFFAOYSA-N O-Xylene Chemical group CC1=CC=CC=C1C CTQNGGLPUBDAKN-UHFFFAOYSA-N 0.000 description 2
- 238000009776 industrial production Methods 0.000 description 2
- ZXEKIIBDNHEJCQ-UHFFFAOYSA-N isobutanol Chemical compound CC(C)CO ZXEKIIBDNHEJCQ-UHFFFAOYSA-N 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- JHGWQSGWUPCKNT-UHFFFAOYSA-N 2-tert-butyl-4-methyl-1,3,5-trinitrobenzene Chemical compound CC1=C([N+]([O-])=O)C=C([N+]([O-])=O)C(C(C)(C)C)=C1[N+]([O-])=O JHGWQSGWUPCKNT-UHFFFAOYSA-N 0.000 description 1
- JQZGUQIEPRIDMR-UHFFFAOYSA-N 3-methylbut-1-yn-1-ol Chemical compound CC(C)C#CO JQZGUQIEPRIDMR-UHFFFAOYSA-N 0.000 description 1
- 229910001018 Cast iron Inorganic materials 0.000 description 1
- 229910000990 Ni alloy Inorganic materials 0.000 description 1
- PXHVJJICTQNCMI-UHFFFAOYSA-N Nickel Chemical compound [Ni] PXHVJJICTQNCMI-UHFFFAOYSA-N 0.000 description 1
- 239000004698 Polyethylene Substances 0.000 description 1
- 239000004721 Polyphenylene oxide Substances 0.000 description 1
- ZLMJMSJWJFRBEC-UHFFFAOYSA-N Potassium Chemical compound [K] ZLMJMSJWJFRBEC-UHFFFAOYSA-N 0.000 description 1
- VQXSOUPNOZTNAI-UHFFFAOYSA-N Pyrethrin I Natural products CC(=CC1CC1C(=O)OC2CC(=O)C(=C2C)CC=C/C=C)C VQXSOUPNOZTNAI-UHFFFAOYSA-N 0.000 description 1
- 239000007868 Raney catalyst Substances 0.000 description 1
- 229910000564 Raney nickel Inorganic materials 0.000 description 1
- ZUQAPLKKNAQJAU-UHFFFAOYSA-N acetylenediol Chemical compound OC#CO ZUQAPLKKNAQJAU-UHFFFAOYSA-N 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- 239000006227 byproduct Substances 0.000 description 1
- 239000003153 chemical reaction reagent Substances 0.000 description 1
- 238000009833 condensation Methods 0.000 description 1
- 230000005494 condensation Effects 0.000 description 1
- 238000006482 condensation reaction Methods 0.000 description 1
- 238000007796 conventional method Methods 0.000 description 1
- 208000012839 conversion disease Diseases 0.000 description 1
- 239000003431 cross linking reagent Substances 0.000 description 1
- 238000005520 cutting process Methods 0.000 description 1
- 230000007547 defect Effects 0.000 description 1
- XNMQEEKYCVKGBD-UHFFFAOYSA-N dimethylacetylene Natural products CC#CC XNMQEEKYCVKGBD-UHFFFAOYSA-N 0.000 description 1
- 238000004821 distillation Methods 0.000 description 1
- LYCAIKOWRPUZTN-UHFFFAOYSA-N ethylene glycol Natural products OCCO LYCAIKOWRPUZTN-UHFFFAOYSA-N 0.000 description 1
- 238000001704 evaporation Methods 0.000 description 1
- 238000002474 experimental method Methods 0.000 description 1
- 239000012847 fine chemical Substances 0.000 description 1
- 230000007062 hydrolysis Effects 0.000 description 1
- 238000006460 hydrolysis reaction Methods 0.000 description 1
- WGCNASOHLSPBMP-UHFFFAOYSA-N hydroxyacetaldehyde Natural products OCC=O WGCNASOHLSPBMP-UHFFFAOYSA-N 0.000 description 1
- 229940035429 isobutyl alcohol Drugs 0.000 description 1
- 238000002955 isolation Methods 0.000 description 1
- 238000006386 neutralization reaction Methods 0.000 description 1
- 229940078552 o-xylene Drugs 0.000 description 1
- 150000002978 peroxides Chemical class 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 229920000570 polyether Polymers 0.000 description 1
- 229920000573 polyethylene Polymers 0.000 description 1
- 229910052700 potassium Inorganic materials 0.000 description 1
- 239000011591 potassium Substances 0.000 description 1
- HYJYGLGUBUDSLJ-UHFFFAOYSA-N pyrethrin Natural products CCC(=O)OC1CC(=C)C2CC3OC3(C)C2C2OC(=O)C(=C)C12 HYJYGLGUBUDSLJ-UHFFFAOYSA-N 0.000 description 1
- VJFUPGQZSXIULQ-XIGJTORUSA-N pyrethrin II Chemical compound CC1(C)[C@H](/C=C(\C)C(=O)OC)[C@H]1C(=O)O[C@@H]1C(C)=C(C\C=C/C=C)C(=O)C1 VJFUPGQZSXIULQ-XIGJTORUSA-N 0.000 description 1
- 238000004064 recycling Methods 0.000 description 1
- 239000002910 solid waste Substances 0.000 description 1
- 235000013599 spices Nutrition 0.000 description 1
- 239000002699 waste material Substances 0.000 description 1
Classifications
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/48—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by oxidation reactions with formation of hydroxy groups
- C07C29/50—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring by oxidation reactions with formation of hydroxy groups with molecular oxygen only
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/78—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by condensation or crystallisation
-
- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C29/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom not belonging to a six-membered aromatic ring
- C07C29/74—Separation; Purification; Use of additives, e.g. for stabilisation
- C07C29/76—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment
- C07C29/86—Separation; Purification; Use of additives, e.g. for stabilisation by physical treatment by liquid-liquid treatment
-
- 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
- Y02P20/50—Improvements relating to the production of bulk chemicals
- Y02P20/52—Improvements relating to the production of bulk chemicals using catalysts, e.g. selective catalysts
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Chemical Kinetics & Catalysis (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
Abstract
The invention provides a method for synthesizing 2, 5-dimethyl-2, 5-hexanediol. The synthetic method comprises the following steps: adding 2, 5-dimethylhexane, an initiator, a catalyst and alkali into a high-pressure reaction kettle; sealing the reaction kettle, and heating to 85-95 ℃; continuously introducing compressed air into the high-pressure reaction kettle, keeping the pressure in the reaction kettle at 4-5bar, and stirring at 85-95 ℃ for reaction; stopping the reaction when the volume concentration of oxygen in the tail gas is more than or equal to 20 percent; layering the obtained reaction liquid, and washing, crystallizing, separating, washing and drying the obtained organic phase to obtain the organic phase. The method adopts a one-step air oxidation method to replace the traditional ethynylation/hydrogenation process, simplifies the reaction flow, improves the safety in the production process of the product, has less waste water generation amount, and is clean, green and environment-friendly; and the conversion rate and the reaction selectivity are high, the yield of the target product is high, and the obtained 2, 5-dimethyl-2, 5-hexanediol meets the index requirement.
Description
Technical Field
The invention relates to a method for synthesizing 2, 5-dimethyl-2, 5-hexanediol, belonging to the technical field of organic synthesis.
Background
2, 5-dimethyl-2, 5-hexanediol is an important fine chemical product and is mainly used for synthesizing pyrethrin, spice, artificial musk, polyethylene plastic cross-linking agent, polyether rubber and the like.
Patent document CN103910606A discloses a method for producing 2, 5-dimethyl-2, 5-hexanediol by an ethynylation condensation method, which comprises the following steps: (1) acetylene and acetone are used as raw materials to prepare feed liquid containing hexynediol; (2) separating by a potassium hydroxide separation kettle; (3) feeding the potassium hydroxide aqueous solution into a nickel alloy continuous evaporator for distillation and concentration of the potassium hydroxide aqueous solution; (4) sending the concentrated potassium hydroxide solution into an inorganic impurity separation device to remove organic impurities; (5) feeding the potassium hydroxide aqueous solution after impurity removal into a cast iron evaporator, and evaporating water to dryness to obtain solid potassium hydroxide; continuously heating to make the solid potassium hydroxide into a molten state, and naturally cooling to recrystallize; (7) and (4) cutting the recrystallized potassium hydroxide into slices by using a slicer, and recycling the slices as a catalyst raw material.
Patent document CN1247181A discloses a one-step synthesis method of 2,5-dimethyl-2,5-hexanediol. The synthesis process includes one-step synthesis of 2, 5-dimethyl-3-acetylene-2, 5-diol with acetylene and acetone in o-xylene solution with potassium isobutyl alcohol as catalyst at normal pressure, hydrolysis, neutralization, concentration, crystallization and centrifugal separation, and hydrogenation at 0-5.5MPa pressure in medium (high) pressure reactor with Raney nickel as catalyst to obtain 2, 5-dimethyl-2, 5-hexanediol.
The conventional process for synthesizing 2, 5-dimethyl-2, 5-hexanediol can be roughly divided into two types: the first method comprises the following steps: acetylene and acetone are subjected to an ethynylation reaction, and then hydrogenation is carried out to obtain 2, 5-dimethyl-2, 5-hexanediol. The process is developed earlier and is the most adopted process in the current industrial production. And the second method comprises the following steps: the methyl butynol-acetone process adopts methyl butynol and acetone as material and through condensation reaction in organic solution to obtain dimethyl acetylene glycol, and subsequent hydrogenation to obtain the product. The process has long flow, more byproducts and no industrial application.
The traditional synthesis methods all require an ethynylation reaction and a hydrogenation reaction, and the reaction process is dangerous, long in flow and large in wastewater amount. The present invention has been made to solve the above problems.
Disclosure of Invention
Aiming at the defects in the prior art, the invention provides a method for synthesizing 2, 5-dimethyl-2, 5-hexanediol. The method adopts a one-step air oxidation method to replace the traditional ethynylation/hydrogenation process, simplifies the reaction flow, improves the safety in the production process of the product, has less waste water generation amount, and is clean, green and environment-friendly; and the conversion rate and the reaction selectivity are high, the yield of the target product is high, and the obtained 2, 5-dimethyl-2, 5-hexanediol meets the index requirement.
The technical scheme of the invention is as follows:
a method for synthesizing 2, 5-dimethyl-2, 5-hexanediol comprises the following steps:
1) Adding 2, 5-dimethylhexane, an initiator, a catalyst and alkali into a high-pressure reaction kettle; sealing the reaction kettle, and heating to 85-95 ℃; continuously introducing compressed air into the high-pressure reaction kettle, keeping the pressure in the reaction kettle at 4-5bar, and carrying out stirring reaction at 85-95 ℃; stopping the reaction when the volume concentration of oxygen in the tail gas is more than or equal to 20 percent;
2) Layering the reaction liquid obtained in the step 1), and washing, crystallizing, separating, washing and drying the obtained organic phase to obtain the 2, 5-dimethyl-2, 5-hexanediol.
According to the present invention, in step 1), the initiator is one or a combination of two or more of cumene hydroperoxide, tert-butyl hydroperoxide or diisopropylbenzene hydroperoxide.
According to the invention, in the step 1), the catalyst is one or a combination of more than two of cobalt naphthenate, cobalt acetate or cobalt stearate.
Preferably, according to the invention, in step 1), the base is an aqueous solution of sodium hydroxide or potassium hydroxide having a concentration of 32 to 50% by weight.
Preferably, in step 1), the mass ratio of 2, 5-dimethylhexane, initiator, catalyst and base is 1:0.002-0.01:0.001-0.01:0.5-2, preferably 1:0.002-0.005:0.001-0.003:0.5-1.
Preferably, according to the invention, in step 1), the reaction temperature is from 88 to 93 ℃.
According to the invention, in step 1), the high-pressure reaction kettle is provided with an air inlet and an air outlet. Compressed air is continuously introduced into the reaction kettle through the air inlet, and then tail gas is discharged out of the reaction kettle through the air outlet.
Preferably, according to the invention, the compressed air is introduced in step 1) at a rate of 20 to 40L/min.
Preferably, according to the invention, in step 1), a pressure of 4.5 to 5bar is maintained in the reaction vessel.
Preferably, according to the invention, in step 2), the organic phase obtained is washed 1 to 3 times with deionized water at 60 to 80 ℃.
Preferably, in step 2), the crystallization method is slow cooling crystallization; preferably, the cooling rate is 0.3-0.8 ℃/min, and the temperature is reduced to 5 ℃.
Preferably, in step 2), the solid obtained by crystallization and isolation is washed 1 to 3 times with 2, 5-dimethylhexane.
Preferably, according to the invention, in step 2), the drying temperature is 60 to 70 ℃ and the drying time is 5 to 6 hours.
Preferably, in step 2), the organic phase is washed, crystallized, separated to obtain a mother liquor, and mixed with the washing liquid obtained by washing 2, 5-dimethylhexane to obtain the next reaction raw material.
Preferably, the mother liquor obtained by washing, crystallizing and separating the obtained organic phase is mixed with the washing liquor obtained by washing 2, 5-dimethylhexane, and when the mother liquor is used as the next reaction raw material, the 2, 5-dimethylhexane is supplemented, and then the next reaction is carried out; further preferably, the specific steps are as follows: adding a mixed solution of a mother solution and a washing solution, 2, 5-dimethylhexane, an initiator, a catalyst and alkali into a high-pressure reaction kettle; sealing the reaction kettle, and heating to 85-95 ℃; continuously introducing compressed air into the high-pressure reaction kettle, keeping the pressure in the reaction kettle at 4-5bar, and carrying out stirring reaction at 85-95 ℃; stopping the reaction when the volume concentration of oxygen in the tail gas is more than or equal to 20 percent; more preferably, the mass ratio of the 2, 5-dimethylhexane to the total mass of the supplemented 2, 5-dimethylhexane, initiator, catalyst and base in the mixed solution is 1:0.002-0.005:0.001-0.003:0.5-1.
According to the invention, a preferable technical scheme is that the synthesis method of the 2, 5-dimethyl-2, 5-hexanediol comprises the following steps:
1) Adding 2, 5-dimethylhexane, an initiator, a catalyst and alkali into a high-pressure reaction kettle with a reflux and stirring device; sealing the reaction kettle, starting condensed water, starting a stirring device, and heating to 85-95 ℃; continuously introducing compressed air into the high-pressure reaction kettle, adjusting a tail gas back pressure valve, keeping the pressure in the reaction kettle at 4-5bar, and carrying out stirring reaction at 85-95 ℃; detecting the oxygen concentration in the tail gas at any time, and stopping the reaction when the volume concentration of the oxygen is more than or equal to 20%;
2) Transferring the reaction liquid obtained in the step 1) into a separating funnel, separating lower-layer wastewater, and washing the obtained organic phase for 1-3 times by using deionized water at the temperature of 60-80 ℃; transferring the obtained organic phase to a crystallization kettle, and slowly cooling and crystallizing; then separating by a Buchner funnel, and washing the obtained solid with fresh 2, 5-dimethylhexane for 1-3 times; then putting the mixture into a forced air drying oven, and drying the mixture for 5 to 6 hours at the temperature of between 60 and 70 ℃ to obtain 2, 5-dimethyl-2, 5-hexanediol; the mother liquor obtained is separated and mixed with the washing liquid obtained by washing fresh 2, 5-dimethylhexane to be used as the raw material of the next reaction.
Preferably, an oxygen concentration online detector is installed in the tail gas discharge pipeline, and the oxygen concentration in the tail gas is detected online.
The invention has the following technical characteristics and beneficial effects:
(1) The method adopts an air oxidation method to synthesize the 2, 5-dimethyl-2, 5-hexanediol by one step, and compared with the traditional process, the method is safer and more environment-friendly, and has simpler operation and less equipment investment.
(2) In the invention, the crystallization mother liquor after the product is separated and the washing liquor obtained by washing the 2, 5-dimethylhexane are used as the raw materials of the next batch of materials, and fresh 2, 5-dimethylhexane is supplemented, so that the generation of waste oil is effectively reduced.
(3) The synthetic method is simple and easy to implement, and has less waste water and solid waste; the reaction conversion rate and selectivity are high, the one-way yield of the target product is about 50%, the mother liquor is reused in combination, and the comprehensive yield of the product is about 80%; the obtained product 2, 5-dimethyl-2, 5-hexanediol has high quality and is suitable for industrial production.
(4) The invention provides a new process route for synthesizing 2, 5-dimethyl-2, 5-hexanediol, which is safer and more environment-friendly, and has shorter flow and simple operation.
Detailed Description
The present invention will be further described with reference to the following examples, but is not limited thereto.
Meanwhile, the experimental methods described in the following examples are all conventional methods unless otherwise specified; the reagents and materials are commercially available, unless otherwise specified.
Example 1
A method for preparing 2, 5-dimethyl-2, 5-hexanediol, comprising the following steps carried out in sequence:
1) Adding 100g of 2, 5-dimethylhexane, 100g of 50wt% aqueous sodium hydroxide solution, 0.2g of cumene hydroperoxide and 0.1g of cobalt naphthenate into a high-pressure reaction kettle, sealing and opening a stirring and condensing device;
2) Slowly heating to 88-90 deg.C, and continuously introducing compressed air; the high-pressure reaction kettle is provided with an air inlet and an air outlet. Compressed air is continuously introduced into the reaction kettle through the air inlet, and then tail gas is discharged out of the reaction kettle through the air outlet; and an oxygen concentration online detector is arranged in the tail gas discharge pipeline so as to detect the oxygen concentration in the tail gas at any time.
3) Continuously introducing compressed air into the high-pressure reaction kettle in the step 2) (the introduction rate of the compressed air is 40L/min), adjusting a tail gas back pressure valve, keeping the pressure of the reaction kettle at 4.5-4.7bar, and carrying out stirring reaction.
4) Detecting the concentration of oxygen in the tail gas at any time, and stopping reaction when the volume concentration of the oxygen is more than or equal to 20%;
5) Transferring the intermediate mixed solution obtained in the step 4) to a separating funnel, separating lower-layer wastewater, and washing the obtained organic phase with 200g of hot deionized water for 2 times, wherein 100g of hot deionized water is used for each time. The temperature is kept between 75 and 80 ℃ in the operation process;
6) Transferring the organic phase obtained in the step 5) to a crystallization kettle, and slowly cooling and crystallizing. Cooling to 5 deg.C, and taking 140min.
7) Separating the solid-liquid mixture obtained in the step 6) by using a Buchner funnel to obtain mother liquor and solid. The solid obtained was washed twice with 25g of fresh 2, 5-dimethylhexane each time to give a washing solution and a wet white solid. The washing solution was mixed with the mother liquor as a raw material for the next reaction. .
8) And (3) putting the white solid wet product into an air drying oven, and drying for 5.5 hours at the temperature of 60-70 ℃ to obtain the pure 2, 5-dimethyl-2, 5-hexanediol product.
9) The mother liquor obtained in step 7) was weighed to obtain 88g.
65.0g of dried 2, 5-dimethyl-2, 5-hexanediol was obtained in this example, and the conversion of 2, 5-dimethylhexane per pass was 62%, the selectivity was 82%, and the yield of the objective product was 50.8%. The product index is shown in the following table:
| index name | Index (es) | Example 1 |
| Main content% | 99.0 | 99.6 |
| Water content is less than or equal to | 0.5 | 0.3 |
| Melting point (DEG C) is not less than | 87.0 | 87.8 |
| Whiteness% greater than or equal to | 90.0 | 95.0 |
| Chroma (platinum-cobalt method) is less than or equal to | 100 | 95 |
| Iodine value (g/100 g) is less than or equal to | 1.0 | 0.8 |
| Unsaturated hydrocarbon (calculated as alkynediol, enediol)% | 0 | 0 |
Example 2
A method for preparing 2, 5-dimethyl-2, 5-hexanediol comprises the following steps of:
1) Adding a mixed solution of the washing solution obtained in the step 7) of example 1 and a mother solution (88 g of the mother solution and 50g of the washing solution), 12g of fresh 2, 5-dimethylhexane, 100g of a 50wt% aqueous solution of sodium hydroxide, 0.2g of cumene hydroperoxide and 0.1g of cobalt naphthenate into a high-pressure reaction kettle, sealing and opening a stirring and condensing device;
2) Slowly heating to 88-90 deg.C, and continuously introducing compressed air; the high-pressure reaction kettle is provided with an air inlet and an air outlet. Compressed air is continuously introduced into the reaction kettle through the air inlet, and then tail gas is discharged out of the reaction kettle through the air outlet; and an oxygen concentration online detector is arranged in the tail gas discharge pipeline so as to detect the oxygen concentration in the tail gas at any time.
3) Continuously introducing compressed air into the high-pressure reaction kettle in the step 2) (the introduction rate of the compressed air is 25L/min), adjusting a tail gas back pressure valve, keeping the pressure of the reaction kettle at 4.5-4.7bar, and carrying out stirring reaction.
4) Detecting the concentration of oxygen in the tail gas at any time, and stopping reaction when the volume concentration of the oxygen is more than or equal to 20%;
5) Transferring the intermediate mixed solution obtained in the step 4) to a separating funnel, separating the lower layer wastewater, and washing the obtained organic phase with 200g of hot deionized water for 2 times, wherein 100g is used for each time. The temperature is kept between 75 and 80 ℃ in the operation process;
6) Transferring the organic phase obtained in the step 5) to a crystallization kettle, and slowly cooling and crystallizing. Cooling to 5 deg.C, and taking 140min.
7) Separating the solid-liquid mixture obtained in the step 6) through a Buchner funnel to obtain mother liquor and solid. The solid obtained was washed twice with 25g of fresh 2, 5-dimethylhexane each time to give a washing solution and a wet white solid. The washing solution was mixed with the mother liquor as a raw material for the next reaction.
8) And (3) putting the white solid wet product into an air drying oven, and drying for 5.5 hours at the temperature of 60-70 ℃ to obtain a pure 2, 5-dimethyl-2, 5-hexanediol product.
9) The mother liquor obtained in step 7) was weighed to obtain 76.5g.
This example was conducted to obtain 76.8g of dry 2, 5-dimethyl-2, 5-hexanediol, a conversion of 73.5% per pass of 2, 5-dimethylhexane, a selectivity of 81.6%, and a yield of the desired product of 60%. The product index is shown in the following table:
| index name | Index (I) | Example 2 |
| Main content% | 99.0 | 99.5 |
| Water content is less than or equal to | 0.5 | 0.2 |
| Melting point (DEG C) of not less than | 87.0 | 87.6 |
| Whiteness% is more than or equal to | 90.0 | 95.0 |
| Chroma (platinum-cobalt method) is less than or equal to | 100 | 95 |
| Iodine value (g/100 g) is less than or equal to | 1.0 | 0.8 |
| Unsaturated hydrocarbon (in terms of acetylenediol, enediol)% | 0 | 0 |
Example 3
2, 5-dimethyl-2, 5-hexanediol was synthesized according to the method of example 2, except that: adjusting the step 1): adding a mixed solution of the washing solution obtained in the step 7) in example 2 and a mother solution (76.5 g of the mother solution and 50g of the washing solution), 23.5g of fresh 2, 5-dimethylhexane, 100g of a 50wt% aqueous sodium hydroxide solution, 0.2g of cumene hydroperoxide and 0.1g of cobalt naphthenate into a high-pressure reaction kettle, sealing and opening a stirring and condensing device; the other steps and conditions were identical to those of example 2.
This example gave 75.5g of mother liquor. 78.2g of 2, 5-dimethyl-2, 5-hexanediol dry product, 74.5% of 2, 5-dimethylhexane conversion per pass, 82.0% of selectivity and 61% of yield of the target product. The product index is shown in the following table:
| index name | Index (I) | Example 3 |
| Main content% | 99.0 | 99.4 |
| Water content is less than or equal to | 0.5 | 0.3 |
| Melting point (DEG C) is not less than | 87.0 | 87.5 |
| Whiteness% greater than or equal to | 90.0 | 95.0 |
| Chroma (platinum-cobalt method) is less than or equal to | 100 | 95 |
| Iodine value (g/100 g) is less than or equal to | 1.0 | 0.6 |
| Unsaturated hydrocarbon (calculated as alkynediol, enediol)% | 0 | 0 |
Example 4
2, 5-dimethyl-2, 5-hexanediol was synthesized according to the method of example 2, except that: adjusting the step 1): a mixed solution of the washing solution and the mother liquor obtained in example 3 (75.5 g of the mother liquor, 50g of the washing solution), 24.5g of fresh 2, 5-dimethylhexane, 100g of a 50wt% aqueous solution of sodium hydroxide, 0.5g of cumene hydroperoxide and 0.3g of cobalt naphthenate were charged into a reaction vessel, and a stirring and condensing device was sealed and opened; the other steps and conditions were identical to those of example 2.
This example gave 76.3g of mother liquor. 78.3g of 2, 5-dimethyl-2, 5-hexanediol dry product, 73.7% of 2, 5-dimethylhexane conversion per pass, 83.0% of selectivity and 61.2% of yield of the target product. The product index is shown in the following table:
| index name | Index (I) | Example 4 |
| Main content% | 99.0 | 99.5 |
| Water content is less than or equal to | 0.5 | 0.1 |
| Melting point (DEG C) is not less than | 87.0 | 87.8 |
| Whiteness% greater than or equal to | 90.0 | 95.0 |
| Chroma (platinum-cobalt method) is less than or equal to | 100 | 95 |
| Iodine value (g/100 g) is less than or equal to | 1.0 | 0.7 |
| Unsaturated hydrocarbon (calculated as alkynediol, enediol)% | 0 | 0 |
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.
Example 5
2, 5-dimethyl-2, 5-hexanediol was synthesized according to the method of example 1, except that: adjusting the step 1): 1) Adding 100g of 2, 5-dimethylhexane, 100g of 32wt% aqueous sodium hydroxide solution, 0.2g of cumene hydroperoxide and 0.1g of cobalt naphthenate into a high-pressure reaction kettle, sealing and starting a stirring and condensing device; the differences are as follows: the concentration of the aqueous sodium hydroxide solution was varied and the other steps and conditions were identical to those of example 1.
This comparative example obtained 44.2g of dried 2, 5-dimethyl-2, 5-hexanediol, 51.5% conversion of 2, 5-dimethylhexane per pass, 67.0% selectivity, and 34.5% yield of the target product.
Comparative example 1
2, 5-dimethyl-2, 5-hexanediol was synthesized according to the method of example 1, except that: adjusting the step 1): 1) 100g of 2, 5-dimethylhexane, 100g of 50wt% aqueous sodium hydroxide solution and 0.2g of cumene hydroperoxide are added to a high-pressure reactor, the reactor is sealed and the stirring and condensing device is opened; the differences are as follows: the cobalt naphthenate was no longer added and the other steps and conditions were identical to those of example 1.
In this comparative example, a dried product of 2, 5-dimethyl-2, 5-hexanediol was not obtained, and it was found that a large amount of peroxide (2, 5-dimethyl-2, 5-dihydroxyhexane) remained in the reaction liquid.
Comparative example 2
2, 5-dimethyl-2, 5-hexanediol was synthesized according to the method of example 1, except that: adjusting the step 1): 1) Adding 100g of 2, 5-dimethylhexane, 100g of 50wt% aqueous solution of sodium hydroxide and 0.1g of cobalt naphthenate into a high-pressure reaction kettle, sealing and opening a stirring and condensing device; the differences are as follows: no further initiator was added and the other steps and conditions were in accordance with example 1.
In this comparative example, a dry product of 2, 5-dimethyl-2, 5-hexanediol was not obtained, and it was found that only a small amount of the starting material had reacted in the reaction solution, and it was judged that the reaction had not been successfully initiated.
Claims (10)
1. A method for synthesizing 2, 5-dimethyl-2, 5-hexanediol comprises the following steps:
1) Adding 2, 5-dimethylhexane, an initiator, a catalyst and alkali into a high-pressure reaction kettle; sealing the reaction kettle, and heating to 85-95 ℃; continuously introducing compressed air into the high-pressure reaction kettle, keeping the pressure in the reaction kettle at 4-5bar, and carrying out stirring reaction at 85-95 ℃; stopping the reaction when the volume concentration of oxygen in the tail gas is more than or equal to 20 percent;
2) Layering the reaction liquid obtained in the step 1), and washing, crystallizing, separating, washing and drying the obtained organic phase to obtain the 2, 5-dimethyl-2, 5-hexanediol.
2. The process for the synthesis of 2, 5-dimethyl-2, 5-hexanediol according to claim 1, characterized in that in step 1) one or more of the following conditions are included:
i. the initiator is one or the combination of more than two of cumene hydroperoxide, tert-butyl hydroperoxide or diisopropylbenzene hydroperoxide;
ii. The catalyst is one or the combination of more than two of cobalt naphthenate, cobalt acetate or cobalt stearate;
iii, the alkali is 32-50wt% sodium hydroxide or potassium hydroxide aqueous solution.
3. The method for synthesizing 2, 5-dimethyl-2, 5-hexanediol according to claim 1, wherein in the step 1), the mass ratio of the 2, 5-dimethylhexane, the initiator, the catalyst and the base is 1:0.002-0.01:0.001-0.01:0.5-2, preferably 1:0.002-0.005:0.001-0.003:0.5-1.
4. The process for the synthesis of 2, 5-dimethyl-2, 5-hexanediol according to claim 1, characterized in that in step 1) one or more of the following conditions are included:
i. the reaction temperature is 88-93 ℃;
ii. The introduction rate of the compressed air is 20-40L/min;
and iii, keeping the pressure in the reaction kettle at 4.5-5bar.
5. The process for the synthesis of 2, 5-dimethyl-2, 5-hexanediol according to claim 1, characterized in that in step 2) one or more of the following conditions are included:
i. washing the obtained organic phase for 1-3 times by using deionized water at the temperature of 60-80 ℃;
ii. The crystallization method is slow cooling crystallization; preferably, the temperature reduction rate is 0.3-0.8 ℃/min, and the temperature is reduced to 5 ℃;
iii, the drying temperature is 60-70 ℃, and the drying time is 5-6 hours.
6. The method for synthesizing 2, 5-dimethyl-2, 5-hexanediol according to claim 1, wherein in the step 2), the solid obtained by crystallization and separation is washed 1 to 3 times with 2, 5-dimethylhexane.
7. The method for synthesizing 2, 5-dimethyl-2, 5-hexanediol according to claim 6, wherein in step 2), the obtained organic phase is washed, crystallized, separated to obtain a mother liquor, and mixed with a washing solution obtained by washing 2, 5-dimethylhexane as a reaction raw material for the next batch.
8. The process for synthesizing 2, 5-dimethyl-2, 5-hexanediol as claimed in claim 7, wherein the organic phase is washed, crystallized, separated to obtain a mother liquor, and mixed with a washing solution obtained by washing 2, 5-dimethylhexane, and when the mother liquor is used as a starting material for the next reaction, the 2, 5-dimethylhexane is additionally added, and then the next reaction is carried out.
9. The method for synthesizing 2, 5-dimethyl-2, 5-hexanediol according to claim 8, wherein the organic phase is washed, crystallized, separated to obtain a mother liquor, and mixed with a washing solution obtained by washing 2, 5-dimethylhexane, as the next reaction raw material, the following steps are carried out: adding a mixed solution of a mother solution and a washing solution, 2, 5-dimethylhexane, an initiator, a catalyst and alkali into a high-pressure reaction kettle; sealing the reaction kettle, and heating to 85-95 ℃; continuously introducing compressed air into the high-pressure reaction kettle, keeping the pressure in the reaction kettle at 4-5bar, and stirring at 85-95 ℃ for reaction; stopping the reaction when the volume concentration of oxygen in the tail gas is more than or equal to 20 percent; preferably, the mass ratio of the 2, 5-dimethylhexane in the mixed solution to the total mass of the supplemented 2, 5-dimethylhexane, the initiator, the catalyst and the base is 1:0.002-0.005:0.001-0.003:0.5-1.
10. The method for synthesizing 2, 5-dimethyl-2, 5-hexanediol according to claim 1, wherein the method for synthesizing 2, 5-dimethyl-2, 5-hexanediol comprises the steps of:
1) Adding 2, 5-dimethylhexane, an initiator, a catalyst and alkali into a high-pressure reaction kettle with a reflux and stirring device; sealing the reaction kettle, starting condensed water, starting a stirring device, and heating to 85-95 ℃; continuously introducing compressed air into the high-pressure reaction kettle, adjusting a tail gas back pressure valve, keeping the pressure in the reaction kettle at 4-5bar, and carrying out stirring reaction at 85-95 ℃; detecting the oxygen concentration in the tail gas at any time, and stopping the reaction when the volume concentration of the oxygen is more than or equal to 20%;
2) Transferring the reaction liquid obtained in the step 1) into a separating funnel, separating lower-layer wastewater, and washing the obtained organic phase for 1-3 times by using deionized water at the temperature of 60-80 ℃; transferring the obtained organic phase to a crystallization kettle, and slowly cooling and crystallizing; then separating by a Buchner funnel, and washing the obtained solid with fresh 2, 5-dimethylhexane for 1-3 times; then putting the mixture into a forced air drying oven, and drying the mixture for 5 to 6 hours at the temperature of between 60 and 70 ℃ to obtain 2, 5-dimethyl-2, 5-hexanediol; the mother liquor obtained is separated and mixed with the washing liquid obtained by washing fresh 2, 5-dimethylhexane to be used as the raw material of the next batch of reaction.
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|---|---|---|---|---|
| CN1247181A (en) * | 1999-08-25 | 2000-03-15 | 成都惟精防水材料研究所 | One-step synthesizing process of 2,5-dimethyl-2,5-hexanediol |
| CN1743311A (en) * | 2005-10-18 | 2006-03-08 | 大庆油田有限责任公司 | Method for synthesizing bifunctionality initiator DIOOH |
| CN1746156A (en) * | 2005-10-18 | 2006-03-15 | 大庆油田有限责任公司 | Synthesis of di-functionality initiator 2,5-MONO |
| CN102285867A (en) * | 2011-06-08 | 2011-12-21 | 四川之江化工新材料有限公司 | Synthesis method of 3-hexyne-2,5-diol |
| CN110615864A (en) * | 2019-10-10 | 2019-12-27 | 万华化学集团股份有限公司 | Methyl methacrylate polymer and preparation method thereof |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN1247181A (en) * | 1999-08-25 | 2000-03-15 | 成都惟精防水材料研究所 | One-step synthesizing process of 2,5-dimethyl-2,5-hexanediol |
| CN1743311A (en) * | 2005-10-18 | 2006-03-08 | 大庆油田有限责任公司 | Method for synthesizing bifunctionality initiator DIOOH |
| CN1746156A (en) * | 2005-10-18 | 2006-03-15 | 大庆油田有限责任公司 | Synthesis of di-functionality initiator 2,5-MONO |
| CN102285867A (en) * | 2011-06-08 | 2011-12-21 | 四川之江化工新材料有限公司 | Synthesis method of 3-hexyne-2,5-diol |
| CN110615864A (en) * | 2019-10-10 | 2019-12-27 | 万华化学集团股份有限公司 | Methyl methacrylate polymer and preparation method thereof |
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