CN105859550A - Dicamba preparation process - Google Patents
Dicamba preparation process Download PDFInfo
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- CN105859550A CN105859550A CN201610295567.5A CN201610295567A CN105859550A CN 105859550 A CN105859550 A CN 105859550A CN 201610295567 A CN201610295567 A CN 201610295567A CN 105859550 A CN105859550 A CN 105859550A
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- C07—ORGANIC CHEMISTRY
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- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/347—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups
- C07C51/367—Preparation of carboxylic acids or their salts, halides or anhydrides by reactions not involving formation of carboxyl groups by introduction of functional groups containing oxygen only in singly bound form
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- C07—ORGANIC CHEMISTRY
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- C07C17/00—Preparation of halogenated hydrocarbons
- C07C17/093—Preparation of halogenated hydrocarbons by replacement by halogens
- C07C17/10—Preparation of halogenated hydrocarbons by replacement by halogens of hydrogen atoms
- C07C17/12—Preparation of halogenated hydrocarbons by replacement by halogens of hydrogen atoms in the ring of aromatic compounds
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- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/01—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis
- C07C37/02—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring by replacing functional groups bound to a six-membered aromatic ring by hydroxy groups, e.g. by hydrolysis by substitution of halogen
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- C07C37/64—Preparation of O-metal compounds with O-metal group bound to a carbon atom belonging to a six-membered aromatic ring
- C07C37/66—Preparation of O-metal compounds with O-metal group bound to a carbon atom belonging to a six-membered aromatic ring by conversion of hydroxy groups to O-metal groups
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- C07—ORGANIC CHEMISTRY
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- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/68—Purification; separation; Use of additives, e.g. for stabilisation
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C37/00—Preparation of compounds having hydroxy or O-metal groups bound to a carbon atom of a six-membered aromatic ring
- C07C37/68—Purification; separation; Use of additives, e.g. for stabilisation
- C07C37/86—Purification; separation; Use of additives, e.g. for stabilisation by treatment giving rise to a chemical modification
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/02—Preparation of carboxylic acids or their salts, halides or anhydrides from salts of carboxylic acids
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/15—Preparation of carboxylic acids or their salts, halides or anhydrides by reaction of organic compounds with carbon dioxide, e.g. Kolbe-Schmitt synthesis
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- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/41—Preparation of salts of carboxylic acids
- C07C51/412—Preparation of salts of carboxylic acids by conversion of the acids, their salts, esters or anhydrides with the same carboxylic acid part
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C51/00—Preparation of carboxylic acids or their salts, halides or anhydrides
- C07C51/42—Separation; Purification; Stabilisation; Use of additives
Abstract
The invention belongs to the technical field of herbicide dicamba preparation and relates to a dicamba preparation process. The dicamba preparation process includes steps: taking benzene as a raw material to generate 1,2,4-trichlorobenzene through directional chlorination, catalysis, re-chlorination and rectification; hydrolyzing the 1,2,4-trichlorobenzene to generate a mixture of 2,5-dichlorophenol and 2,4-dichlorophenol, and separating and purifying to obtain 2,5-dichlorophenol; using the 2,5-dichlorophenol to prepare 3,6-dichlorosalicylic acid; subjecting the 3,6-dichlorosalicylic acid to methylation, saponification, acidification and the like to obtain dicamba. By optimization of technical steps and parameters, the whole dicamba preparation process has advantages of simplicity, low cost, high yield, high selectivity, remarkable reduction of wastewater and increase of equipment utilization rate.
Description
Technical field
The present invention relates to the preparation technology of a kind of herbicide, be specifically related to the preparation technology of a kind of Mediben, belong to preparation
Herbicide dicamba technical field.
Background technology
Mediben belongs to benzoic acid system herbicide, has Uptake and translocation effect, to annual and perennial broadleaf weed
Having notable preventive effect, Mediben is sprayed after the seedling, medicament can quickly by the leaf of weeds, stem, root absorption, by bast to
Upper and lower conduction, focuses mostly at the vigorous position of separate living tissue and metabolic activity, hinders the normal activity of plant hormone, so that
It is dead.Grass absorbs and can quickly carry out metabolic breakdown after medicament and be allowed to lose efficacy therefore the stronger resistance to the action of a drug of performance.Right
The gramineous crops such as wheat, corn, millet, paddy rice are safer, and Mediben disappears in soil after microorganism is comparatively fast decomposed,
I.e. there will be deformity curling symptom with latter general 24 hours broad leaved weeds, 15-20 days dead.At present, the production of Mediben is main
Concentrate on the Sandoz company of BASF Corp. of Germany and Switzerland, domestic mainly Zhejiang Shenghua Biok Biology Co., Ltd.
And raise agrochemicals.
Mediben is in the preparation technology of prior art, and its synthetic route mainly has following several: (1) patent
US4161611 is with 2-amido-3, and 6-dichlorobenzoic acid is raw material, reacts through diazotising, hydrolysis, carboxylation, methylate etc. and is prepared for
Mediben.The Mediben product content that the method obtains is higher, but total recovery is on the low side, relatively costly, and is made in the method
Raw material sources difficulty, this is its weak point.(2) patent DE2331712 is with 2, and 5-bis-chloro-4-bromophenol is raw material,
Generating 2-hydroxyl-5-bromo-3,6-dybenal through formaldehyde hydroxymethylation, then after methyl-etherified reacts, debrominate generates 2-again
Methoxyl group-3,6-dybenal, finally reoxidize generation target molecule 2-methoxyl group-3,6-dichlorobenzoic acid.This method raw material is not
Preferably obtaining, yield is the highest, lacks industrialized condition.(3) patent US3345157 is with 2, and 5-chlorophenesic acid is raw material so that it is at hydrogen-oxygen
Changing and react generation pi-allyl-2 under sodium effect with 3-chloropropene, 5-dichloro phenylate, then in the methanol solution of potassium hydroxide
Heating, isomerization generates 2-acrylic-3,6-chlorophenesic acid, then obtains 2-propylene with dimethyl suflfate by methylation reaction
Base-3,6-Banair, finally under the effect of nitric acid and ammonium vanadate, backflow has obtained target molecule 2-methoxyl group-3,6-bis-
Chlorobenzoic acid.The weak point of this process route is reaction time length, energy consumption is high, yield is relatively low.(4) patent US4232172 with
2,5-chlorophenesic acids are raw material, under refined potassium carbonate effect, with CO2Through section's bohr-Schmidt's carboxylation reaction, then use sulphur
Dimethyl phthalate carries out O-alkylated reaction and prepares Mediben.Current industrial many producing in this way, its weak point is anti-
Between Ying Shi long, energy consumption is high.(5) patent CN201010584645.6 discloses the preparation technology of a kind of herbicide dicamba, its with
2,5-chlorophenesic acids are raw material, after being made into corresponding phenol sodium, complete carboxylation reaction in the supercritical state and obtain 3,6-
Dichlorosalicylic acid, then complete O-with dimethyl carbonate for reagent and methylate prepared product Mediben.The method reaction condition requirement
Height, the time is long.(6) patent US3928432 is that raw material is anti-through debrominate, oxidation with 5-bromo-3,6-bis-chloro-2-methoxy benzyl alcohol
Should, or 5-bromo-3, the chloro-HBA of 6-bis-be primary raw material through debrominate, methylate, oxidation reaction obtains product.But
Initiation material is not readily available.
In said method (5), the preparation method of 2,5-chlorophenesic acid raw materials also has multiple, and chlorine can be used benzene chlorination to be become
Trichloro-benzenes, the most separated purification of trichloro-benzenes, hydrolysis obtain 2,5-chlorophenesic acid, patent CN200410019755.2 discloses a chlorine
Benzene catalyst oriented chlorination produces with fractionation, high-purity 1,2,4-trichloro-benzenes and the preparation method of para-dichlorobenzene.The method is: logical
Cross after monochloro-benzene and chlorine reaction generate dichloro-benzenes, mixed dichlorobenzene is obtained 99.5～99.8% contraposition dichloro through rectifying
Benzene；Again by after mixed dichlorobenzene and chlorine reaction certain time, rectifying, finally give 1,2,4-trichloro-benzenes 99.5% finished product.This is special
Profit is suitable for producing 1,2,4-trichloro-benzenes and para-dichlorobenzene, the productivity of trichloro-benzenes and inefficiency simultaneously, is not suitable for extensive raw
Produce trichloro-benzenes.Additionally trichloro-benzenes purifies 1,2,4-trichloro-benzenes, the most external main employing molecular sieve adsorption analytic method and molecular sieve
Selective isomerization process technology, but the operating procedure of both approaches is complicated, product purity is low.Domestic use with to, adjacent
Dichloro-benzenes or the isolation technics rectifying crystallization technique the same to chlorine system aromatic isomers such as, ortho-chlorotolu'enes, but rectifying crystallization is right
Rectifying device requires the highest, and investment of production cost is high, and product purity is limited, and economic benefit is not good enough.And for example Publication No.
CN1088569, the patent of invention of entitled " separating-purifying 1, the method for 2,4-trichloro-benzenes from mixed trichlorobenzene ", this patent is adopted
The method adding emulsion washing by solvent recrystallization purifies 1,2,4-trichloro-benzenes, but purification process needs to add 1,2,4-trichloro-benzenes
Crystal seed, and the time purified is long, process simplifies not, there is the defect that efficiency is low, cost is high, is not suitable for industrialized production.
State Intellectual Property Office discloses Publication No. CN102942474A in 2013.2.27, and entitled " one is removed
The synthesis technique of grass agent Mediben " invention, this disclosure of the invention preparation method of a kind of herbicide dicamba, including (1) liquid
Body potassium hydroxide and 2,5-chlorophenesic acid obtain 2,5-chlorophenesic acid potassium with the molar ratio reaction of 0.95:1 ~ 1:1；(2) step (1)
The 2 of gained, 5-chlorophenesic acid potassium, in the presence of Anhydrous potassium carbonate and catalyst, reacts production 3,6-dichlorosalicylic acid with CO2；Control
The pressure of CO2 processed is 4 ~ 6MPa, reaction temperature 100 ~ 160 DEG C, Anhydrous potassium carbonate and 2, the mol ratio of 5-chlorophenesic acid potassium is 1 ~
2:1；(3) in the basic conditions, at a temperature of 70 ~ 100 DEG C, by step (2) gained 3,1:1 pressed by 6-dichlorosalicylic acid and chloromethanes
The mol ratio of ~ 3.5, through calandria type fixed bed reactor, is reacted under the effect of catalyst, then obtains 3 through saponification, acidifying,
6-bis-chloro-2-methoxysalicylic acid, i.e. Mediben.The technological reaction yield of the present invention is high, reaction condition is simple, product quality
Well, the three wastes are few, energy consumption is low.In the method, production cost is the highest, and moisture requires harshness, and the reaction time is long, in reaction
Tar content is high, and selectivity of product is low.This process yield is less than 85-90%, and yield is low, and saponification time is long, and wastewater flow rate is relatively big, equipment
Utilization rate is relatively low.
Summary of the invention
The present invention is directed to the deficiency in above-mentioned technique, it is provided that the preparation technology of a kind of Mediben, by preparation technology,
The optimization of process for separating and purifying so that each section of product yield of technique and product purity increase substantially, excess raw material and by-product
Thing is effectively utilized, and has that preparation technology is simple, low cost, yield are high, selectivity is high, wastewater flow rate significantly reduces, equipment
The advantage that utilization rate improves.
In order to realize foregoing invention purpose, technical scheme is as follows:
The preparation technology of a kind of Mediben, comprises the following steps that:
A. oriented chlorination
Being passed through in benzene by chlorine, under catalyst action, oriented chlorination obtains paracide and o-dichlorohenzene mixture；Described chlorine
Gas is 1.8～2.2:1 with the ratio of the amount of the material of benzene；
B. catalytic treatment
The paracide obtained to step A and o-dichlorohenzene mixture add lewis acid catalyst process；
Chlorination the most again, rectifying
Being passed through chlorine in the mixed liquor that the catalytic treatment of step B obtains, chlorination obtains 1,2,4-trichloro-benzenes, paracide and adjacent two
The mixture of chlorobenzene；Described chlorine is 0.5～2:1 with the amount ratio of the material of mixed liquor；After the mixture rectifying that will obtain, respectively
Obtain 1,2,4-trichloro-benzenes product and unreacted dichloro-benzenes mixture；Described dichloro-benzenes mixture is returned to step as raw material
B, recycles；
D, by 1,2,4-trichloro-benzenes hydrolysis, then will obtain 2 after hydrolysate rectifying, 5-chlorophenesic acid and 2, the mixing of 4-chlorophenesic acid
Thing；
E, 2 step D obtained, 5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying, obtains 2,5-bis-
Chlorophenol；
F, under nitrogen protection, by 2,5-chlorophenesic acid is dissolved in dimethylbenzene, prepares 2, the xylene solution of 5-chlorophenesic acid, so
After potassium hydroxide aqueous solution is under agitation added dropwise to 2, in the xylene solution of 5-chlorophenesic acid, drip complete, be heated to boiling
Rise, distillation, when moisture reaches below 2000ppm in the dimethylbenzene that mensuration distillates, stop distillation, obtain 2,5-chlorophenesic acid potassium
Xylene solution；
G, 2 step F obtained, the xylene solution of 5-chlorophenesic acid potassium proceeds in autoclave, adds catalyst potassium carbonate, helps
Catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene and carboxymethylcellulose calcium, stir and evenly mix, be passed through carbon dioxide,
Displaced air, continues after being replaced to be passed through carbon dioxide, absorbing carbon dioxide 5-10min under the pressure of 3-5MPa；Heat up
To 140-170 DEG C, pressure is maintained at 5.5-7.5MPa, stirring lower reaction 1-4 hour, is then cooled to 50-80 DEG C, pressure release, mistake
Filter, filtrate is 2, the xylene solution of 5-chlorophenesic acid potassium, and filter cake is 3,6-dichlorosalicylic acid potassium and potassium carbonate；
H, 3 step G obtained, 6-dichlorosalicylic acid potassium and potassium carbonate filter cake are dissolved in water, and drip hydrochloric acid acidifying, then stir
Cooling, crystallization, filter, washing, obtain 3,6-dichlorosalicylic acid wet product, finally it is dried to obtain 3,6-dichlorosalicylic acid；
I, by 3,6-dichlorosalicylic acid is dissolved in alkali lye, pumps into the flow reactor that methylates, and is filled with methyl chloride gas, is simultaneously added dropwise
Alkali lye and the methanol solution of catalyst, carry out methylation reaction, treats that methylation reaction terminates, and pressure release obtains methylation reaction liquid；
J, methylation reaction liquid step I obtained enter saponification flow reactor, add alkali lye, keep reaction temperature 100-
140 DEG C, pressure 0.10-0.50MPa, time 0.2-1.5h, reaction is complete, is cooled to 30-90 DEG C, and pressure release obtains saponification liquid；
K, saponification liquid step J obtained enter destilling tower, Distillation recovery methyl alcohol；
L, the tower bed material liquid of destilling tower described in step K is entered acidification reaction device, filter after acidification reaction, obtain Mediben wet
Product, drying, obtain Mediben dry product.
In step A of the present invention, in step A, the catalyst that described oriented chlorination uses is antimony trisulfide, described antimony trisulfide and benzene
Mass ratio be 0.001～0.05:1.
The temperature of described oriented chlorination is 60～65 DEG C.
In step B, the temperature of described catalytic treatment is 100～200 DEG C, and the process time is 2～8h.
In step B, described lewis acid catalyst is anhydrous ferric trichloride or aluminum trichloride (anhydrous), and described catalyst is with right
The mass ratio of dichloro-benzenes and o-dichlorohenzene mixture is 0.01～0.1:1.
In step C, the catalyst that described chlorination uses is anhydrous ferric trichloride and sulphur powder, and described anhydrous ferric trichloride is with mixed
The mass ratio closing liquid is 0.001～0.05:1, and described sulphur powder is 0.001～0.01:1 with the mass ratio of mixed liquor.
In step C, the reaction temperature of described chlorination is 60～65 DEG C.
In step C, in distillation process, the pressure of rectifying column is 10～50mmHg.
The present invention in step E, described 2,5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying,
Obtaining 2,5-chlorophenesic acid is particularly as follows: to 2,5-chlorophenesic acid and 2, addition urea in the mixture of 4-chlorophenesic acid, in 90-
At 120 DEG C after reaction, it is cooled to less than 90 DEG C, is subsequently adding organic solvent, suction filtration after cooling, obtain filtrate and filter cake；To filter
Adding water in cake, be warming up to 60-90 DEG C, continue reaction, then separatory, obtain organic phase and aqueous phase, organic phase is 2,5-dichloro
Phenol；After filtrate is sloughed organic solvent, obtain 2,5-chlorophenesic acid and 2,4-dichlorophenol mixture；To 2,5-chlorophenesic acid
With 2,4-dichlorophenol mixture adds water and the ammoniacal liquor of mixture total mole number 0.5-1.5 times amount, is warming up to 40-80 DEG C,
Continue reaction, carry out filtering for the first time after solution temperature is down to room temperature, in filter cake, then add water, be warming up to 40-80 DEG C,
Then lowering the temperature, carry out second time and filter, obtain filtrate and filter cake, described filter cake is 2,4-chlorophenesic acid；Described second time filters
To filtrate be 2 after dehydration, 5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid, this mixture is back to addition urea
Link, then circulates operation, until the sterling separation rate of 2,5-chlorophenesic acids reaches more than 95%, and the sterling of 2,4-chlorophenesic acids
Separation rate reaches more than 85%.
The present invention in step E, described 2,5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying,
Obtain 2,5-chlorophenesic acid particularly as follows: to 2,5-chlorophenesic acid and 2, the mixed liquor of 4-chlorophenesic acid adds organic solvent, so
Rear dropping alkali hydroxide soln or alkali-metal weak acid strong alkali salt solution, and insulated and stirred at 40-80 DEG C, then rise
Temperature point water less than 1000ppm, after being cooled to room temperature, suction filtration, obtains filtrate and filter cake to system moisture；After the acidifying of described filter cake
Obtain 2,5-chlorophenesic acid；Described filtrate, after decompression Distillation recovery organic solvent, obtains mixed liquor, standby；To de-organic solvent
After the mixed liquor that obtains drips ammonia spirit, suction filtration after stirring, in filter cake, then add organic solvent recrystallization, obtain 2,4-
Chlorophenesic acid.
The present invention is in step F, and described 2,5-chlorophenesic acid is 1:4-6 with the mass ratio of dimethylbenzene.
The present invention is in step F, and described 2,5-chlorophenesic acid is 1:0.30-0.40 with the mass ratio of potassium hydroxide.
The present invention is in step F, when in the dimethylbenzene that described mensuration distillates, moisture reaches below 1500ppm, stops
Distillation.
The present invention in step F, described in be replaced after continue to be passed through carbon dioxide after absorb under the pressure of 3-5MPa
Carbon dioxide 5-10min.
The present invention, in step F, reacts 1.5-2.5 hour under described stirring.
The present invention is in step G, and described catalyst potassium carbonate and 2, the mass ratio of 5-chlorophenesic acid is 0.40-0.70:1.
The present invention in step G, described co-catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxylic first
The gross mass of base cellulose is the 0.5-10% of potassium carbonate quality.
The present invention in step G, described 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxymethylcellulose calciums
Mass ratio be 1:1-5.
Aforementioned proportion is preferably 1:1.7-3.5.
The present invention is in step G, and the xylene solution of described 2,5-chlorophenesic acid potassium directly returns autoclave dispensing to be carried out
Phenolic acid nak response.
In steph, described acidifying is specially dropping hydrochloric acid and is acidified to pH value is 1-3 to the present invention, controls temperature 40-100
DEG C, react 10-120min.
In steph, described stirring is cooled to be cooled to less than 20 DEG C the present invention.
The present invention is in step I, and total mol ratio of the alkali in described 3,6-dichlorosalicylic acid and twice alkali lye is 1:3-5.
The present invention is in step I, and described alkali is potassium hydroxide, NaOH, potassium carbonate, saleratus, sodium carbonate, carbonic acid
Any one or two kinds of arbitrary proportion in hydrogen sodium.
The present invention is in step I, and described catalyst is TBAB, tetrabutylammonium chloride or benzyl triethyl ammonium chlorination
Ammonium.
The present invention is in step I, and described catalyst and 3, the mass ratio of 6-dichlorosalicylic acid is 0.1-5:100.
The present invention is in step I, and described catalyst is 1-10:100 with the mass ratio of methyl alcohol.
The present invention is in step I, and described methylation reaction is particularly as follows: keep reaction temperature 60-100 DEG C, pressure 0.40-
0.80MPa, time 3-7h, regulation pH is 8.0-13.0.
The present invention is in step J, and described 3,6-dichlorosalicylic acid is 1:1-1.6 with the mol ratio of alkali.
The present invention is in step L, and described acidification reaction, particularly as follows: add water, drips hydrochloric acid, regulates pH to 0.5-3, stirring
Under be cooled to 0-25 DEG C.
The Advantageous Effects that the present invention brings is as follows:
1, the present invention is by preparation technology, the optimization of process for separating and purifying so that each section of product yield of technique and product are pure
Degree increases substantially, and excess raw material and accessory substance are effectively utilized, and has that preparation technology is simple, low cost, yield high, choosing
The advantage that selecting property is high, wastewater flow rate significantly reduces, utilization rate of equipment and installations improves.
Specifically, the present invention develops one novel 1, and the production technology of 2,4-trichloro-benzenes first passes through purified petroleum benzin
Oriented chlorination obtains paracide and o-dichlorohenzene, then with Louis's acid as catalyst by this paracide and o-dichlorohenzene
Mixture carries out catalytic treatment, changes dichloro-benzenes mixture ratio, significantly reduces dichloro-benzenes mixture chlorination reaction activation energy, make
This dichloro-benzenes mixture is prone to high conversion, highly selective is chlorinated into 1,2,4-trichloro-benzenes, and chlorination reaction liquid is after rectifying
Finally giving the 1 of high purity more than 98%, 2,4-trichloro-benzenes, rectifying simultaneously obtains unreacted paracide and o-dichlorohenzene
Mixture is also used as raw material and is circulated and applies mechanically, and significantly reduces production cost and process byproducts.To sum up, present invention tool
Have that method is simple, low cost, productivity high, process byproducts is few, the advantage being suitable for large-scale industrial production.Trichloro-benzenes is purified
Obtaining 1, after 2,4-trichloro-benzenes, then through hydrolysis, prepare the mixture of chlorophenesic acid, the mixture of chlorophenesic acid is through separating further
Obtaining 2,5-chlorophenesic acid, technical process is easily controllable, and the purity of product is high.
2, in step A of the present invention, described chlorine is 1.8～2.2:1 with the ratio of the amount of the material of benzene, and amount of chlorine crosses that I haven't seen you for ages makes
Depth of chlorination causes not the conversion ratio of dichloro-benzenes low, and amount of chlorine too much can make depth of chlorination excessive and cause impurity content to increase
Add, therefore this ratio is optimal.
3, in step A of the present invention, the catalyst that described oriented chlorination uses is antimony trisulfide, described antimony trisulfide and the quality of benzene
Ratio is 0.001～0.05:1, and the catalytic effect of antimony trisulfide oriented chlorination is fine, and its consumption can reduce oriented chlorination not and become dichloro
The conversion ratio of benzene, consumption too much can increase impurity content and increase production cost, therefore this ratio is optimal.
4, in step A of the present invention and/or step C, the temperature of described chlorination is 60～65 DEG C, and the setting of this temperature range was both
The paracide solidification that when temperature can be prevented too low, oriented chlorination generates, is avoided that again the while that when temperature is too high, chlorination reaction being very fast
Produce more impurity, therefore this temperature range is optimal.
5, in step B of the present invention, the temperature of described catalytic treatment is 100～200 DEG C, and the process time is 2～8h, at catalysis
Reason is the committed step of the present invention, the temperature of catalytic treatment, the time inadequate or long catalysis that all can cause dichloro-benzenes mixture
Treatment effect is the best, and high conversion, highly selective cannot be chlorinated into 1, and 2,4-trichloro-benzenes are verified through test of many times, should
The best results that temperature and time processes.
6, in step B of the present invention, described lewis acid catalyst is anhydrous ferric trichloride or aluminum trichloride (anhydrous), described in urge
Agent is 0.01～0.1:1 with the mass ratio of paracide and o-dichlorohenzene mixture, anhydrous ferric trichloride and anhydrous tri-chlorination
Aluminium is common lewis acid, and it is cheap and easy to get and catalytic treatment effect is good；Anhydrous ferric trichloride or aluminum trichloride (anhydrous) consumption
Not enough or too much dichloro-benzenes mixture through catalytic treatment effect all can be caused the best, the most also can increase production cost.
7, in step C of the present invention, described chlorine is 0.5～2:1 with the amount ratio of the material of mixed liquor；Amount of chlorine crosses that I haven't seen you for ages makes
Depth of chlorination causes 1 not, and the conversion ratio of 2,4-trichloro-benzenes is low, and amount of chlorine too much can make depth of chlorination excessive and cause impurity
Content increases.
8, in step C of the present invention, the catalyst that described chlorination uses is anhydrous ferric trichloride and sulphur powder, described anhydrous trichlorine
The mass ratio changing iron and mixed liquor is 0.001～0.05:1, and described sulphur powder is 0.001～0.01:1 with the mass ratio of mixed liquor,
Anhydrous ferric trichloride is common chlorination reaction catalyst, and sulphur powder is also common chlorination reaction co-catalyst, all has inexpensive
It is easy to get and feature that catalytic reaction is effective；The consumption of anhydrous ferric trichloride and sulphur powder can reduce turning of 1,2,4-trichloro-benzenes not
Rate, consumption too much can increase impurity content and increase production cost.
9, the 2 of step E of the present invention, 5-chlorophenesic acid and 2, the process for separation and purification of 4-chlorophenesic acid has two kinds, the first,
Urea addition, AMMONIA TREATMENT method: isolate most 2 by urea addition process, 5-chlorophenesic acid, then molten by ammoniacal liquor
Solving, crystallize, separate, by most 2,4-chlorophenesic acid is separated, and finally repeats urea and AMMONIA TREATMENT step, by 2,5-
Chlorophenesic acid, 2,4-chlorophenesic acid is completely isolated, and after testing, the separation rate of 2,5-chlorophenesic acids has reached more than 95%, 2,4-
The separation rate of chlorophenesic acid has reached more than 85%；Compared with method of the prior art, the processing cost of this processing method is low,
Operating procedure is simple, less energy consumption, is suitable for industrialized production.
Second method is then to utilize 2,5-chlorophenesic acid and 2,4-chlorophenesic acid difference on Acidity of Aikalinity, and reaction
2 generated, the feature such as the 5-chlorophenesic acid alkali metal salt low precipitable separation of solubility in selected organic solvent, by from
Solution, extraction, band water, precipitate, the operation such as filtration by 2, after 5-chlorophenesic acid is separated, then become salt, organic solvent by ammoniacal liquor
The steps such as recrystallization, by 2,4-chlorophenesic acid is separated, and is arranged by the special parameter of each operation, especially divides water to body
In system, moisture is less than 1000ppm, it is ensured that substantially anhydrous in reaction system, so that generate 2,5-chlorophenesic acid alkali metal salt
Fully Precipitation, to reach the purpose separated.
10, in step F of the present invention, G, H, high pressure carboxylation requires height to content of water in system, it is desirable to aqueous below 50ppm, carboxylic
Changing the reaction time long, product yield is with the lowest, and potassium carbonate consumption is big, produces the problem that tar is many, it is provided that a kind of 3,6-bis-
The preparation method of chloro-salicylic acid, the method uses specific process and technological parameter, coordinates specific co-catalyst, to instead
System moisture is answered to require to reduce, as long as reaching below 2000ppm, it is not necessary to drop to below 50ppm, reduce band shipwreck
Degree, saves the time.Technical process simplifies, and reduces the reaction time, improves product yield and selectivity, reduces production cost.Specific
The addition of co-catalyst, is substantially reduced potassium carbonate consumption, reduces the carboxylation reaction time；In reaction, tar content reduces, and product selects
Property high.In prior art, generally after pressure release, add water, add hydrochloric acid acidifying, filter out solid product 3,6-dichlorosalicylic acid, filter
Liquid carries out split-phase, and organic phase is 2, and 5-chlorophenesic acid xylene solution returns in step F, drips potassium hydroxide aqueous solution, is formed
The xylene solution of 2,5-chlorophenesic acid potassium.The present invention directly filters after pressure release, gained 2, the dimethylbenzene of 5-chlorophenesic acid potassium
Solution can be returned directly to the reaction under high pressure stage, recycles, and reduces the usage amount of potassium hydroxide, reduces the cost of raw material, reduces
Production cost.
11, in step J of the present invention, solving existing employing 3, it is low that 6-dichlorosalicylic acid prepares Mediben process recovery ratio, soap
The change time is long, and wastewater flow rate is relatively big, the problem that utilization rate of equipment and installations is relatively low, it is provided that a kind of employing 3,6-dichlorosalicylic acid prepares Mediben
Technique, it is possible to being greatly improved yield, the saponification time shortens, and wastewater flow rate significantly reduces, and utilization rate of equipment and installations improves.Existing skill
In art saponification, generally using back flow reaction under normal pressure, its reaction time is long, it is possible to create the fracture of methoxyl group key, phenyl ring
On fall down the side reactions such as chlorine, and decarboxylation, cause whole reaction yield low (with 3,6-dichlorosalicylic acid meter 85-90%), accessory substance
Many, waste residue amount is big；The present invention uses under the conditions of specified temp, specified pressure and special time, 3,6-dichlorosalicylic acid ether-ethers
Carrying out saponification, almost orientation reaction in the basic conditions, yield is high, and with 3,6-dichlorosalicylic acid is calculated as 98-99%.
12, present invention process can more preferably realize automation, continuous prodution.
Detailed description of the invention
Embodiment 1
The preparation technology of a kind of Mediben, comprises the following steps that:
A. oriented chlorination
Being passed through in benzene by chlorine, under catalyst action, oriented chlorination obtains paracide and o-dichlorohenzene mixture；Described chlorine
Gas is 1.8:1 with the ratio of the amount of the material of benzene；
B. catalytic treatment
The paracide obtained to step A and o-dichlorohenzene mixture add lewis acid catalyst process；
Chlorination the most again, rectifying
Being passed through chlorine in the mixed liquor that the catalytic treatment of step B obtains, chlorination obtains 1,2,4-trichloro-benzenes, paracide and adjacent two
The mixture of chlorobenzene；The amount of described chlorine and the material of mixed liquor is than for 0.5:1；After the mixture rectifying that will obtain, respectively
To 1,2,4-trichloro-benzenes product and unreacted dichloro-benzenes mixture；Described dichloro-benzenes mixture is returned to step B as raw material,
Recycle；
D, by 1,2,4-trichloro-benzenes hydrolysis, then will obtain 2 after hydrolysate rectifying, 5-chlorophenesic acid and 2, the mixing of 4-chlorophenesic acid
Thing；
E, 2 step D obtained, 5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying, obtains 2,5-bis-
Chlorophenol；
F, under nitrogen protection, by 2,5-chlorophenesic acid is dissolved in dimethylbenzene, prepares 2, the xylene solution of 5-chlorophenesic acid, so
After potassium hydroxide aqueous solution is under agitation added dropwise to 2, in the xylene solution of 5-chlorophenesic acid, drip complete, be heated to boiling
Rise, distillation, when moisture reaches below 2000ppm in the dimethylbenzene that mensuration distillates, stop distillation, obtain 2,5-chlorophenesic acid potassium
Xylene solution；
G, 2 step F obtained, the xylene solution of 5-chlorophenesic acid potassium proceeds in autoclave, adds catalyst potassium carbonate, helps
Catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene and carboxymethylcellulose calcium, stir and evenly mix, be passed through carbon dioxide,
Displaced air, continues after being replaced to be passed through carbon dioxide, absorbing carbon dioxide 5min under the pressure of 3MPa；It is warming up to 140
DEG C, pressure is maintained at 5.5MPa, the lower reaction of stirring 1 hour, is then cooled to 50 DEG C, and pressure release is filtered, and filtrate is 2,5-dichloro-benzenes
The xylene solution of phenol potassium, filter cake is 3,6-dichlorosalicylic acid potassium and potassium carbonate；
H, 3 step G obtained, 6-dichlorosalicylic acid potassium and potassium carbonate filter cake are dissolved in water, and drip hydrochloric acid acidifying, then stir
Cooling, crystallization, filter, washing, obtain 3,6-dichlorosalicylic acid wet product, finally it is dried to obtain 3,6-dichlorosalicylic acid；
I, by 3,6-dichlorosalicylic acid is dissolved in alkali lye, pumps into the flow reactor that methylates, and is filled with methyl chloride gas, is simultaneously added dropwise
Alkali lye and the methanol solution of catalyst, carry out methylation reaction, treats that methylation reaction terminates, and pressure release obtains methylation reaction liquid；
J, methylation reaction liquid step I obtained enter saponification flow reactor, add alkali lye, keep reaction temperature 100 DEG C,
Pressure 0.10MPa, time 0.2h, reaction is complete, is cooled to 30 DEG C, and pressure release obtains saponification liquid；
K, saponification liquid step J obtained enter destilling tower, Distillation recovery methyl alcohol；
L, the tower bed material liquid of destilling tower described in step K is entered acidification reaction device, filter after acidification reaction, obtain Mediben wet
Product, drying, obtain Mediben dry product.
Embodiment 2
The preparation technology of a kind of Mediben, comprises the following steps that:
A. oriented chlorination
Being passed through in benzene by chlorine, under catalyst action, oriented chlorination obtains paracide and o-dichlorohenzene mixture；Described chlorine
Gas is 2.0:1 with the ratio of the amount of the material of benzene；
B. catalytic treatment
The paracide obtained to step A and o-dichlorohenzene mixture add lewis acid catalyst process；
Chlorination the most again, rectifying
Being passed through chlorine in the mixed liquor that the catalytic treatment of step B obtains, chlorination obtains 1,2,4-trichloro-benzenes, paracide and adjacent two
The mixture of chlorobenzene；The amount of described chlorine and the material of mixed liquor is than for 1.5:1；After the mixture rectifying that will obtain, respectively
To 1,2,4-trichloro-benzenes product and unreacted dichloro-benzenes mixture；Described dichloro-benzenes mixture is returned to step B as raw material,
Recycle；
D, by 1,2,4-trichloro-benzenes hydrolysis, then will obtain 2 after hydrolysate rectifying, 5-chlorophenesic acid and 2, the mixing of 4-chlorophenesic acid
Thing；
E, 2 step D obtained, 5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying, obtains 2,5-bis-
Chlorophenol；
F, under nitrogen protection, by 2,5-chlorophenesic acid is dissolved in dimethylbenzene, prepares 2, the xylene solution of 5-chlorophenesic acid, so
After potassium hydroxide aqueous solution is under agitation added dropwise to 2, in the xylene solution of 5-chlorophenesic acid, drip complete, be heated to boiling
Rise, distillation, when moisture reaches below 2000ppm in the dimethylbenzene that mensuration distillates, stop distillation, obtain 2,5-chlorophenesic acid potassium
Xylene solution；
G, 2 step F obtained, the xylene solution of 5-chlorophenesic acid potassium proceeds in autoclave, adds catalyst potassium carbonate, helps
Catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene and carboxymethylcellulose calcium, stir and evenly mix, be passed through carbon dioxide,
Displaced air, continues after being replaced to be passed through carbon dioxide, absorbing carbon dioxide 8min under the pressure of 4MPa；It is warming up to 155
DEG C, pressure is maintained at 6.0MPa, the lower reaction of stirring 2.5 hours, is then cooled to 65 DEG C, and pressure release is filtered, and filtrate is 2,5-dichloro
The xylene solution of potassium phenate, filter cake is 3,6-dichlorosalicylic acid potassium and potassium carbonate；
H, 3 step G obtained, 6-dichlorosalicylic acid potassium and potassium carbonate filter cake are dissolved in water, and drip hydrochloric acid acidifying, then stir
Cooling, crystallization, filter, washing, obtain 3,6-dichlorosalicylic acid wet product, finally it is dried to obtain 3,6-dichlorosalicylic acid；
I, by 3,6-dichlorosalicylic acid is dissolved in alkali lye, pumps into the flow reactor that methylates, and is filled with methyl chloride gas, is simultaneously added dropwise
Alkali lye and the methanol solution of catalyst, carry out methylation reaction, treats that methylation reaction terminates, and pressure release obtains methylation reaction liquid；
J, methylation reaction liquid step I obtained enter saponification flow reactor, add alkali lye, keep reaction temperature 120 DEG C,
Pressure 0.30MPa, time 1.8h, reaction is complete, is cooled to 60 DEG C, and pressure release obtains saponification liquid；
K, saponification liquid step J obtained enter destilling tower, Distillation recovery methyl alcohol；
L, the tower bed material liquid of destilling tower described in step K is entered acidification reaction device, filter after acidification reaction, obtain Mediben wet
Product, drying, obtain Mediben dry product.
Embodiment 3
The preparation technology of a kind of Mediben, comprises the following steps that:
A. oriented chlorination
Being passed through in benzene by chlorine, under catalyst action, oriented chlorination obtains paracide and o-dichlorohenzene mixture；Described chlorine
Gas is 2.2:1 with the ratio of the amount of the material of benzene；
B. catalytic treatment
The paracide obtained to step A and o-dichlorohenzene mixture add lewis acid catalyst process；
Chlorination the most again, rectifying
Being passed through chlorine in the mixed liquor that the catalytic treatment of step B obtains, chlorination obtains 1,2,4-trichloro-benzenes, paracide and adjacent two
The mixture of chlorobenzene；The amount of described chlorine and the material of mixed liquor is than for 2:1；After the mixture rectifying that will obtain, respectively obtain
1,2,4-trichloro-benzenes product and unreacted dichloro-benzenes mixture；Described dichloro-benzenes mixture is returned to step B as raw material, follows
Ring utilizes；
D, by 1,2,4-trichloro-benzenes hydrolysis, then will obtain 2 after hydrolysate rectifying, 5-chlorophenesic acid and 2, the mixing of 4-chlorophenesic acid
Thing；
E, 2 step D obtained, 5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying, obtains 2,5-bis-
Chlorophenol；
F, under nitrogen protection, by 2,5-chlorophenesic acid is dissolved in dimethylbenzene, prepares 2, the xylene solution of 5-chlorophenesic acid, so
After potassium hydroxide aqueous solution is under agitation added dropwise to 2, in the xylene solution of 5-chlorophenesic acid, drip complete, be heated to boiling
Rise, distillation, when moisture reaches below 2000ppm in the dimethylbenzene that mensuration distillates, stop distillation, obtain 2,5-chlorophenesic acid potassium
Xylene solution；
G, 2 step F obtained, the xylene solution of 5-chlorophenesic acid potassium proceeds in autoclave, adds catalyst potassium carbonate, helps
Catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene and carboxymethylcellulose calcium, stir and evenly mix, be passed through carbon dioxide,
Displaced air, continues after being replaced to be passed through carbon dioxide, absorbing carbon dioxide 10min under the pressure of 5MPa；It is warming up to 170
DEG C, pressure is maintained at 7.5MPa, the lower reaction of stirring 4 hours, is then cooled to 80 DEG C, and pressure release is filtered, and filtrate is 2,5-dichloro-benzenes
The xylene solution of phenol potassium, filter cake is 3,6-dichlorosalicylic acid potassium and potassium carbonate；
H, 3 step G obtained, 6-dichlorosalicylic acid potassium and potassium carbonate filter cake are dissolved in water, and drip hydrochloric acid acidifying, then stir
Cooling, crystallization, filter, washing, obtain 3,6-dichlorosalicylic acid wet product, finally it is dried to obtain 3,6-dichlorosalicylic acid；
I, by 3,6-dichlorosalicylic acid is dissolved in alkali lye, pumps into the flow reactor that methylates, and is filled with methyl chloride gas, is simultaneously added dropwise
Alkali lye and the methanol solution of catalyst, carry out methylation reaction, treats that methylation reaction terminates, and pressure release obtains methylation reaction liquid；
J, methylation reaction liquid step I obtained enter saponification flow reactor, add alkali lye, keep reaction temperature 140 DEG C,
Pressure 0.50MPa, time 1.5h, reaction finish, be cooled to 90 DEG C, pressure release, obtain saponification liquid；
K, saponification liquid step J obtained enter destilling tower, Distillation recovery methyl alcohol；
L, the tower bed material liquid of destilling tower described in step K is entered acidification reaction device, filter after acidification reaction, obtain Mediben wet
Product, drying, obtain Mediben dry product.
Embodiment 4
On the basis of embodiment 1-3: in step A of the present invention, in step A, the catalyst that described oriented chlorination uses is sulfuration
Antimony, described antimony trisulfide is 0.001:1 with the mass ratio of benzene.
The temperature of described oriented chlorination is 60 DEG C.
In step B, the temperature of described catalytic treatment is 100 DEG C, and the process time is 2h.
In step B, described lewis acid catalyst is anhydrous ferric trichloride or aluminum trichloride (anhydrous), and described catalyst is with right
The mass ratio of dichloro-benzenes and o-dichlorohenzene mixture is 0.01:1.
In step C, the catalyst that described chlorination uses is anhydrous ferric trichloride and sulphur powder, and described anhydrous ferric trichloride is with mixed
The mass ratio closing liquid is 0.001:1, and described sulphur powder is 0.01:1 with the mass ratio of mixed liquor.
In step C, the reaction temperature of described chlorination is 60 DEG C.
In step C, in distillation process, the pressure of rectifying column is 10mmHg.
Embodiment 5
On the basis of embodiment 1-3: in step A of the present invention, in step A, the catalyst that described oriented chlorination uses is sulfuration
Antimony, described antimony trisulfide is 0.03:1 with the mass ratio of benzene.
The temperature of described oriented chlorination is 63 DEG C.
In step B, the temperature of described catalytic treatment is 150 DEG C, and the process time is 5h.
In step B, described lewis acid catalyst is anhydrous ferric trichloride or aluminum trichloride (anhydrous), and described catalyst is with right
The mass ratio of dichloro-benzenes and o-dichlorohenzene mixture is 0.05:1.
In step C, the catalyst that described chlorination uses is anhydrous ferric trichloride and sulphur powder, and described anhydrous ferric trichloride is with mixed
The mass ratio closing liquid is 0.003:1, and described sulphur powder is 0.005:1 with the mass ratio of mixed liquor.
In step C, the reaction temperature of described chlorination is 63 DEG C.
In step C, in distillation process, the pressure of rectifying column is 30mmHg.
Embodiment 6
On the basis of embodiment 1-3: in step A of the present invention, in step A, the catalyst that described oriented chlorination uses is sulfuration
Antimony, described antimony trisulfide is 0.05:1 with the mass ratio of benzene.
The temperature of described oriented chlorination is 65 DEG C.
In step B, the temperature of described catalytic treatment is 200 DEG C, and the process time is 8h.
In step B, described lewis acid catalyst is anhydrous ferric trichloride or aluminum trichloride (anhydrous), and described catalyst is with right
The mass ratio of dichloro-benzenes and o-dichlorohenzene mixture is 0.1:1.
In step C, the catalyst that described chlorination uses is anhydrous ferric trichloride and sulphur powder, and described anhydrous ferric trichloride is with mixed
The mass ratio closing liquid is 0.05:1, and described sulphur powder is 0.01:1 with the mass ratio of mixed liquor.
In step C, the reaction temperature of described chlorination is 65 DEG C.
In step C, in distillation process, the pressure of rectifying column is 50mmHg.
Embodiment 7
On the basis of embodiment 1-3: the present invention in step E, described 2,5-chlorophenesic acid and 2, the mixing of 4-chlorophenesic acid
Thing carries out separating, purifying, and obtains 2, and 5-chlorophenesic acid is particularly as follows: to 2,5-chlorophenesic acid and 2, in the mixture of 4-chlorophenesic acid
Add urea, at 90 DEG C reaction after, be cooled to less than 90 DEG C, be subsequently adding organic solvent, suction filtration after cooling, obtain filtrate and
Filter cake；Adding water in filter cake, be warming up to 60 DEG C, continue reaction, then separatory, obtain organic phase and aqueous phase, organic phase is 2,
5-chlorophenesic acid；After filtrate is sloughed organic solvent, obtain 2,5-chlorophenesic acid and 2,4-dichlorophenol mixture；To 2,5-bis-
Chlorophenol and 2, adds water and the ammoniacal liquor of mixture total mole number 0.5 times amount, is warming up to 40 DEG C, continues in 4-dichlorophenol mixture
Continuous reaction, carries out filtering for the first time after solution temperature is down to room temperature, then adds water in filter cake, is warming up to 40 DEG C, then
Cooling, carries out second time and filters, obtain filtrate and filter cake, and described filter cake is 2,4-chlorophenesic acid；Described second time is filtrated to get
Filtrate is 2 after dehydration, 5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid, and this mixture is back to add the ring of urea
Joint, then circulates operation, until the sterling separation rate of 2,5-chlorophenesic acids reaches more than 95%, the sterling of 2,4-chlorophenesic acids is divided
More than 85% is reached from rate.
The present invention in step E, described 2,5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying,
Obtain 2,5-chlorophenesic acid particularly as follows: to 2,5-chlorophenesic acid and 2, the mixed liquor of 4-chlorophenesic acid adds organic solvent, so
Rear dropping alkali hydroxide soln or alkali-metal weak acid strong alkali salt solution, and insulated and stirred at 40 DEG C, then heat up
Divide water to system moisture less than 1000ppm, after being cooled to room temperature, suction filtration, obtain filtrate and filter cake；After the acidifying of described filter cake
To 2,5-chlorophenesic acid；Described filtrate, after decompression Distillation recovery organic solvent, obtains mixed liquor, standby；After de-organic solvent
The mixed liquor obtained drips ammonia spirit, suction filtration after stirring, in filter cake, then adds organic solvent recrystallization, obtain 2,4-bis-
Chlorophenol.
Embodiment 8
On the basis of embodiment 1-3: the present invention in step E, described 2,5-chlorophenesic acid and 2, the mixing of 4-chlorophenesic acid
Thing carries out separating, purifying, and obtains 2, and 5-chlorophenesic acid is particularly as follows: to 2,5-chlorophenesic acid and 2, in the mixture of 4-chlorophenesic acid
Add urea, at 115 DEG C after reaction, be cooled to less than 90 DEG C, be subsequently adding organic solvent, suction filtration after cooling, obtain filtrate
And filter cake；Adding water in filter cake, be warming up to 75 DEG C, continue reaction, then separatory, obtain organic phase and aqueous phase, organic phase is
2,5-chlorophenesic acid；After filtrate is sloughed organic solvent, obtain 2,5-chlorophenesic acid and 2,4-dichlorophenol mixture；To 2,5-
Chlorophenesic acid and 2, adds water and the ammoniacal liquor of mixture total mole number 1.0 times amount, is warming up to 60 DEG C in 4-dichlorophenol mixture,
Continue reaction, carry out filtering for the first time after solution temperature is down to room temperature, in filter cake, then add water, be warming up to 60 DEG C, so
Rear cooling, carries out second time and filters, obtain filtrate and filter cake, and described filter cake is 2,4-chlorophenesic acid；Described second time is filtrated to get
Filtrate through dehydration after be 2,5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid, this mixture be back to addition urea ring
Joint, then circulates operation, until the sterling separation rate of 2,5-chlorophenesic acids reaches more than 95%, the sterling of 2,4-chlorophenesic acids is divided
More than 85% is reached from rate.
The present invention in step E, described 2,5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying,
Obtain 2,5-chlorophenesic acid particularly as follows: to 2,5-chlorophenesic acid and 2, the mixed liquor of 4-chlorophenesic acid adds organic solvent, so
Rear dropping alkali hydroxide soln or alkali-metal weak acid strong alkali salt solution, and insulated and stirred at 60 DEG C, then heat up
Divide water to system moisture less than 1000ppm, after being cooled to room temperature, suction filtration, obtain filtrate and filter cake；After the acidifying of described filter cake
To 2,5-chlorophenesic acid；Described filtrate, after decompression Distillation recovery organic solvent, obtains mixed liquor, standby；After de-organic solvent
The mixed liquor obtained drips ammonia spirit, suction filtration after stirring, in filter cake, then adds organic solvent recrystallization, obtain 2,4-bis-
Chlorophenol.
Embodiment 9
On the basis of embodiment 1-3: the present invention in step E, described 2,5-chlorophenesic acid and 2, the mixing of 4-chlorophenesic acid
Thing carries out separating, purifying, and obtains 2, and 5-chlorophenesic acid is particularly as follows: to 2,5-chlorophenesic acid and 2, in the mixture of 4-chlorophenesic acid
Add urea, at 120 DEG C after reaction, be cooled to less than 90 DEG C, be subsequently adding organic solvent, suction filtration after cooling, obtain filtrate
And filter cake；Adding water in filter cake, be warming up to 90 DEG C, continue reaction, then separatory, obtain organic phase and aqueous phase, organic phase is
2,5-chlorophenesic acid；After filtrate is sloughed organic solvent, obtain 2,5-chlorophenesic acid and 2,4-dichlorophenol mixture；To 2,5-
Chlorophenesic acid and 2, adds water and the ammoniacal liquor of mixture total mole number 1.5 times amount, is warming up to 80 DEG C in 4-dichlorophenol mixture,
Continue reaction, carry out filtering for the first time after solution temperature is down to room temperature, in filter cake, then add water, be warming up to 80 DEG C, so
Rear cooling, carries out second time and filters, obtain filtrate and filter cake, and described filter cake is 2,4-chlorophenesic acid；Described second time is filtrated to get
Filtrate through dehydration after be 2,5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid, this mixture be back to addition urea ring
Joint, then circulates operation, until the sterling separation rate of 2,5-chlorophenesic acids reaches more than 95%, the sterling of 2,4-chlorophenesic acids is divided
More than 85% is reached from rate.
The present invention in step E, described 2,5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying,
Obtain 2,5-chlorophenesic acid particularly as follows: to 2,5-chlorophenesic acid and 2, the mixed liquor of 4-chlorophenesic acid adds organic solvent, so
Rear dropping alkali hydroxide soln or alkali-metal weak acid strong alkali salt solution, and insulated and stirred at 80 DEG C, then heat up
Divide water to system moisture less than 1000ppm, after being cooled to room temperature, suction filtration, obtain filtrate and filter cake；After the acidifying of described filter cake
To 2,5-chlorophenesic acid；Described filtrate, after decompression Distillation recovery organic solvent, obtains mixed liquor, standby；After de-organic solvent
The mixed liquor obtained drips ammonia spirit, suction filtration after stirring, in filter cake, then adds organic solvent recrystallization, obtain 2,4-bis-
Chlorophenol.
Embodiment 10
On the basis of embodiment 1-3: the present invention is in step F, and described 2,5-chlorophenesic acid is 1 with the mass ratio of dimethylbenzene:
6。
The present invention is in step F, and described 2,5-chlorophenesic acid is 1:0.30 with the mass ratio of potassium hydroxide.
The present invention is in step F, when in the dimethylbenzene that described mensuration distillates, moisture reaches below 1500ppm, stops
Distillation.
The present invention in step F, described in be replaced after continue to be passed through carbon dioxide after under the pressure of 3MPa, absorb two
Carbonoxide 5min.
The present invention, in step F, reacts 1.5 hours under described stirring.
The present invention is in step G, and described catalyst potassium carbonate and 2, the mass ratio of 5-chlorophenesic acid is 0.40:1.
The present invention in step G, described co-catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxylic first
The gross mass of base cellulose is the 0.5% of potassium carbonate quality.
The present invention in step G, described 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxymethylcellulose calciums
Mass ratio be 1:1.
Aforementioned proportion is preferably 1:1.7.
The present invention is in step G, and the xylene solution of described 2,5-chlorophenesic acid potassium directly returns autoclave dispensing to be carried out
Phenolic acid nak response.
In steph, described acidifying is specially dropping hydrochloric acid and is acidified to pH value is 1 to the present invention, controls temperature 40 DEG C, instead
Answer 10min.
In steph, described stirring is cooled to be cooled to less than 20 DEG C the present invention.
Embodiment 11
On the basis of embodiment 1-3: the present invention is in step F, and described 2,5-chlorophenesic acid is 1 with the mass ratio of dimethylbenzene:
4-6。
The present invention is in step F, and described 2,5-chlorophenesic acid is 1:0.35 with the mass ratio of potassium hydroxide.
The present invention is in step F, when in the dimethylbenzene that described mensuration distillates, moisture reaches below 1500ppm, stops
Distillation.
The present invention in step F, described in be replaced after continue to be passed through carbon dioxide after under the pressure of 4MPa, absorb two
Carbonoxide 7min.
The present invention, in step F, reacts 2.0 hours under described stirring.
The present invention is in step G, and described catalyst potassium carbonate and 2, the mass ratio of 5-chlorophenesic acid is 0.50:1.
The present invention in step G, described co-catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxylic first
The gross mass of base cellulose is the 5% of potassium carbonate quality.
The present invention in step G, described 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxymethylcellulose calciums
Mass ratio be 1:3.
Aforementioned proportion is preferably 1:2.5.
The present invention is in step G, and the xylene solution of described 2,5-chlorophenesic acid potassium directly returns autoclave dispensing to be carried out
Phenolic acid nak response.
In steph, described acidifying is specially dropping hydrochloric acid and is acidified to pH value is 2 to the present invention, controls temperature 70 C, instead
Answer 50min.
In steph, described stirring is cooled to be cooled to less than 20 DEG C the present invention.
Embodiment 12
On the basis of embodiment 1-3: the present invention is in step F, and described 2,5-chlorophenesic acid is 1 with the mass ratio of dimethylbenzene:
6。
The present invention is in step F, and described 2,5-chlorophenesic acid is 1:0.40 with the mass ratio of potassium hydroxide.
The present invention is in step F, when in the dimethylbenzene that described mensuration distillates, moisture reaches below 1500ppm, stops
Distillation.
The present invention in step F, described in be replaced after continue to be passed through carbon dioxide after under the pressure of 5MPa, absorb two
Carbonoxide 10min.
The present invention, in step F, reacts 2.5 hours under described stirring.
The present invention is in step G, and described catalyst potassium carbonate and 2, the mass ratio of 5-chlorophenesic acid is 0.70:1.
The present invention in step G, described co-catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxylic first
The gross mass of base cellulose is the 10% of potassium carbonate quality.
The present invention in step G, described 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxymethylcellulose calciums
Mass ratio be 1:5.
Aforementioned proportion is preferably 1:3.5.
The present invention is in step G, and the xylene solution of described 2,5-chlorophenesic acid potassium directly returns autoclave dispensing to be carried out
Phenolic acid nak response.
In steph, described acidifying is specially dropping hydrochloric acid and is acidified to pH value is 3 to the present invention, controls temperature 100 DEG C, instead
Answer 120min.
In steph, described stirring is cooled to be cooled to less than 20 DEG C the present invention.
Embodiment 13
On the basis of embodiment 1-3: in steph, described acidifying is specially dropping hydrochloric acid and is acidified to pH value is 1 to the present invention,
Control temperature 40 DEG C, react 10min.
In steph, described stirring is cooled to be cooled to less than 20 DEG C the present invention.
The present invention is in step I, and total mol ratio of the alkali in described 3,6-dichlorosalicylic acid and twice alkali lye is 1:3.
The present invention is in step I, and described alkali is potassium hydroxide.
The present invention is in step I, and described catalyst is TBAB.
The present invention is in step I, and described catalyst and 3, the mass ratio of 6-dichlorosalicylic acid is 0.1:100.
The present invention is in step I, and described catalyst is 1:100 with the mass ratio of methyl alcohol.
The present invention in step I, described methylation reaction particularly as follows: keep reaction temperature 60 DEG C, pressure 0.40MPa, time
Between 3h, regulation pH be 8.0.
The present invention is in step J, and described 3,6-dichlorosalicylic acid is 1:1 with the mol ratio of alkali.
The present invention is in step L, and described acidification reaction, particularly as follows: add water, drips hydrochloric acid, regulates pH to 0.5, under stirring
It is cooled to 0 DEG C.
Embodiment 14
On the basis of embodiment 1-3: in steph, described acidifying is specially dropping hydrochloric acid and is acidified to pH value is 2 to the present invention,
Control temperature 70 C, react 70min.
In steph, described stirring is cooled to be cooled to less than 20 DEG C the present invention.
The present invention is in step I, and total mol ratio of the alkali in described 3,6-dichlorosalicylic acid and twice alkali lye is 1:4.
The present invention is in step I, and described alkali is potassium carbonate.
The present invention is in step I, and described catalyst is tetrabutylammonium chloride.
The present invention is in step I, and described catalyst and 3, the mass ratio of 6-dichlorosalicylic acid is 3:100.
The present invention is in step I, and described catalyst is 5:100 with the mass ratio of methyl alcohol.
The present invention in step I, described methylation reaction particularly as follows: keep reaction temperature 80 DEG C, pressure 0.60MPa, time
Between 5h, regulation pH be 10.0.
The present invention is in step J, and described 3,6-dichlorosalicylic acid is 1:1.3 with the mol ratio of alkali.
The present invention is in step L, and described acidification reaction, particularly as follows: add water, drips hydrochloric acid, regulates pH to 2.0, under stirring
It is cooled to 12 DEG C.
Embodiment 15
On the basis of embodiment 1-3: in steph, described acidifying is specially dropping hydrochloric acid and is acidified to pH value is 3 to the present invention,
Control temperature 100 DEG C, react 120min.
In steph, described stirring is cooled to be cooled to less than 20 DEG C the present invention.
The present invention is in step I, and total mol ratio of the alkali in described 3,6-dichlorosalicylic acid and twice alkali lye is 1:5.
The present invention is in step I, and described alkali is sodium acid carbonate.
The present invention is in step I, and described catalyst is benzyltriethylammoinium chloride.
The present invention is in step I, and described catalyst and 3, the mass ratio of 6-dichlorosalicylic acid is 5:100.
The present invention is in step I, and described catalyst is 10:100 with the mass ratio of methyl alcohol.
The present invention in step I, described methylation reaction particularly as follows: keep reaction temperature 100 DEG C, pressure 0.80MPa, time
Between 7h, regulation pH be 13.0.
The present invention is in step J, and described 3,6-dichlorosalicylic acid is 1:1.6 with the mol ratio of alkali.
The present invention is in step L, and described acidification reaction, particularly as follows: add water, drips hydrochloric acid, regulates pH to 3, cold under stirring
But to 25 DEG C.
Claims (10)
1. the preparation technology of a Mediben, it is characterised in that: comprise the following steps that:
The preparation technology of a kind of Mediben, comprises the following steps that:
A. oriented chlorination
Being passed through in benzene by chlorine, under catalyst action, oriented chlorination obtains paracide and o-dichlorohenzene mixture；Described chlorine
Gas is 1.8～2.2:1 with the ratio of the amount of the material of benzene；
B. catalytic treatment
The paracide obtained to step A and o-dichlorohenzene mixture add lewis acid catalyst process；
Chlorination the most again, rectifying
Being passed through chlorine in the mixed liquor that the catalytic treatment of step B obtains, chlorination obtains 1,2,4-trichloro-benzenes, paracide and adjacent two
The mixture of chlorobenzene；Described chlorine is 0.5～2:1 with the amount ratio of the material of mixed liquor；After the mixture rectifying that will obtain, respectively
Obtain 1,2,4-trichloro-benzenes product and unreacted dichloro-benzenes mixture；Described dichloro-benzenes mixture is returned to step as raw material
B, recycles；
D, by 1,2,4-trichloro-benzenes hydrolysis, then will obtain 2 after hydrolysate rectifying, 5-chlorophenesic acid and 2, the mixing of 4-chlorophenesic acid
Thing；
E, 2 step D obtained, 5-chlorophenesic acid and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying, obtains 2,5-bis-
Chlorophenol；
F, under nitrogen protection, by 2,5-chlorophenesic acid is dissolved in dimethylbenzene, prepares 2, the xylene solution of 5-chlorophenesic acid, so
After potassium hydroxide aqueous solution is under agitation added dropwise to 2, in the xylene solution of 5-chlorophenesic acid, drip complete, be heated to boiling
Rise, distillation, when moisture reaches below 2000ppm in the dimethylbenzene that mensuration distillates, stop distillation, obtain 2,5-chlorophenesic acid potassium
Xylene solution；
G, 2 step F obtained, the xylene solution of 5-chlorophenesic acid potassium proceeds in autoclave, adds catalyst potassium carbonate, helps
Catalyst 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene and carboxymethylcellulose calcium, stir and evenly mix, be passed through carbon dioxide,
Displaced air, continues after being replaced to be passed through carbon dioxide, absorbing carbon dioxide 5-10min under the pressure of 3-5MPa；Heat up
To 140-170 DEG C, pressure is maintained at 5.5-7.5MPa, stirring lower reaction 1-4 hour, is then cooled to 50-80 DEG C, pressure release, mistake
Filter, filtrate is 2, the xylene solution of 5-chlorophenesic acid potassium, and filter cake is 3,6-dichlorosalicylic acid potassium and potassium carbonate；
H, 3 step G obtained, 6-dichlorosalicylic acid potassium and potassium carbonate filter cake are dissolved in water, and drip hydrochloric acid acidifying, then stir
Cooling, crystallization, filter, washing, obtain 3,6-dichlorosalicylic acid acid wet product, finally it is dried to obtain 3,6-dichlorosalicylic acid；
I, by 3,6-dichlorosalicylic acid is dissolved in alkali lye, pumps into the flow reactor that methylates, and is filled with methyl chloride gas, is simultaneously added dropwise
Alkali lye and the methanol solution of catalyst, carry out methylation reaction, treats that methylation reaction terminates, and pressure release obtains methylation reaction liquid；
J, methylation reaction liquid step I obtained enter saponification flow reactor, add alkali lye, keep reaction temperature 100-
140 DEG C, pressure 0.10-0.50MPa, time 0.2-1.5h, reaction is complete, is cooled to 30-90 DEG C, and pressure release obtains saponification liquid；
K, saponification liquid step J obtained enter destilling tower, Distillation recovery methyl alcohol；
L, the tower bed material liquid of destilling tower described in step K is entered acidification reaction device, filter after acidification reaction, obtain Mediben wet
Product, drying, obtain Mediben dry product.
The preparation technology of a kind of Mediben the most according to claim 1, it is characterised in that: in step A, described oriented chlorination
The catalyst used is antimony trisulfide, and described antimony trisulfide is 0.001～0.05:1 with the mass ratio of benzene.
The preparation technology of a kind of Mediben the most according to claim 2, it is characterised in that: in step A and/or step C, institute
The temperature stating chlorination is 60～65 DEG C.
The preparation technology of a kind of Mediben the most according to claim 1, it is characterised in that: in step B, described catalytic treatment
Temperature be 100～200 DEG C, the process time is 2～8h；Described lewis acid catalyst is anhydrous ferric trichloride or anhydrous trichlorine
Changing aluminium, described catalyst is 0.01～0.1:1 with the mass ratio of paracide and o-dichlorohenzene mixture.
The preparation technology of a kind of Mediben the most according to claim 1, it is characterised in that: in step C, described chlorination uses
Catalyst be anhydrous ferric trichloride and sulphur powder, the mass ratio of described anhydrous ferric trichloride and mixed liquor is 0.001～0.05:1,
Described sulphur powder is 0.001～0.01:1 with the mass ratio of mixed liquor.
The preparation technology of a kind of Mediben the most according to claim 1, it is characterised in that: in step E, described 2,5-bis-
Chlorophenol and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying, obtains 2,5-chlorophenesic acid particularly as follows: to 2,5-dichloro-benzenes
Phenol and 2, adds urea, at 90-120 DEG C after reaction, is cooled to less than 90 DEG C, is subsequently adding in the mixture of 4-chlorophenesic acid
Organic solvent, suction filtration after cooling, obtain filtrate and filter cake；In filter cake, add water, be warming up to 60-90 DEG C, continue reaction, then
Separatory, obtains organic phase and aqueous phase, and organic phase is 2,5-chlorophenesic acid；After filtrate is sloughed organic solvent, obtain 2,5-dichloro
Phenol and 2,4 dichloro benzene phenol mixture；In 2,5-chlorophenesic acid with 2,4 dichloro benzene phenol mixture, add water and mixture is total
The ammoniacal liquor of molal quantity 0.5-1.5 times amount, is warming up to 40-80 DEG C, continues reaction, carries out for the first time after solution temperature is down to room temperature
Filter, in filter cake, then add water, be warming up to 40-80 DEG C, then lower the temperature, carry out second time and filter, obtain filtrate and filter cake, institute
Stating filter cake is 2,4 dichloro phenol；The filtrate that described second time is filtrated to get is 2,5-chlorophenesic acid and 2,4-dichloro after dehydration
The mixture of phenol, this mixture is back to add the link of urea, then circulates operation, until the sterling of 2,5-chlorophenesic acids
Separation rate reaches more than 95%, and the sterling separation rate of 2,4-chlorophenesic acids reaches more than 85%.
The preparation technology of a kind of Mediben the most according to claim 1, it is characterised in that: in step E, described 2,5-bis-
Chlorophenol and 2, the mixture of 4-chlorophenesic acid carries out separating, purifying, obtains 2,5-chlorophenesic acid particularly as follows: to 2,5-dichloro-benzenes
Phenol and 2, adds organic solvent, then dropping alkali hydroxide soln or alkali-metal weak in the mixed liquor of 4-chlorophenesic acid
Acid highly basic salting liquid, and insulated and stirred at 40-80 DEG C, point water that then heats up, cools down to system moisture less than 1000ppm
To room temperature, suction filtration, obtain filtrate and filter cake；2,5-chlorophenesic acid is obtained after the acidifying of described filter cake；Described filtrate is through decompression distillation
After reclaiming organic solvent, obtain mixed liquor, standby；The mixed liquor obtained after de-organic solvent drips ammonia spirit, after stirring
Suction filtration, then adds organic solvent recrystallization in filter cake, obtains 2,4-chlorophenesic acid.
The preparation technology of a kind of Mediben the most according to claim 1, it is characterised in that: in step F, described mensuration evaporates
When moisture reaches below 1500ppm in the dimethylbenzene gone out, stop distillation.
The preparation technology of a kind of Mediben the most according to claim 1, it is characterised in that: in step G, described co-catalysis
The 0.5-that gross mass is potassium carbonate quality of agent 1,5,7-tri-azabicyclo [4,4,0] certain herbaceous plants with big flowers-5-alkene (TBD) and carboxymethylcellulose calcium
10%。
The preparation technology of a kind of Mediben the most according to claim 1, it is characterised in that: in step I, described alkali is
Any one or two kinds of arbitrary proportion in potassium hydroxide, NaOH, potassium carbonate, saleratus, sodium carbonate, sodium acid carbonate；
Described catalyst is TBAB, tetrabutylammonium chloride or benzyltriethylammoinium chloride；Described methylation reaction particularly as follows:
Keeping reaction temperature 60-100 DEG C, pressure 0.40-0.80MPa, time 3-7h, regulation pH is 8.0-13.0.
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|---|---|---|---|---|
| CN109096099A (en) * | 2018-09-28 | 2018-12-28 | 萧县新秀新材料有限公司 | The production method of 3,5- di-tert-butyl-4-hydroxybenzoic acid |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3462498A (en) * | 1965-09-10 | 1969-08-19 | Boehringer Sohn Ingelheim | Process for isolation of 2,5-dichlorophenol from an isomeric mixture of dichlorophenols |
| WO1997045389A1 (en) * | 1996-05-28 | 1997-12-04 | Occidental Chemical Corporation | Method of making 1,2,4-trichlorobenzene |
| GB2341178B (en) * | 1998-09-02 | 2000-08-02 | Gharda Chemicals Limited | Process for the separation of Dichlorophenol Isomers |
| CN101781175A (en) * | 2009-12-29 | 2010-07-21 | 浙江工业大学 | Method for separating 2,4-Dichlorophenol and 2,6-Dichlorophenol |
| CN102942474A (en) * | 2012-11-26 | 2013-02-27 | 江苏扬农化工股份有限公司 | Synthetic process of herbicide dicamba |
| CN103819307A (en) * | 2014-02-12 | 2014-05-28 | 葫芦岛锦化化工工程设计有限公司 | Method for preparing chlorobenzene, p-dichlorobenzene and o-dichlorobenzene in benzene chlorination |
| WO2015049360A1 (en) * | 2013-10-04 | 2015-04-09 | Basf Se | Selective hydrolysis and alcoholysis of chlorinated benzenes |
-
2016
- 2016-05-06 CN CN201610295567.5A patent/CN105859550B/en active Active
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3462498A (en) * | 1965-09-10 | 1969-08-19 | Boehringer Sohn Ingelheim | Process for isolation of 2,5-dichlorophenol from an isomeric mixture of dichlorophenols |
| WO1997045389A1 (en) * | 1996-05-28 | 1997-12-04 | Occidental Chemical Corporation | Method of making 1,2,4-trichlorobenzene |
| GB2341178B (en) * | 1998-09-02 | 2000-08-02 | Gharda Chemicals Limited | Process for the separation of Dichlorophenol Isomers |
| CN101781175A (en) * | 2009-12-29 | 2010-07-21 | 浙江工业大学 | Method for separating 2,4-Dichlorophenol and 2,6-Dichlorophenol |
| CN102942474A (en) * | 2012-11-26 | 2013-02-27 | 江苏扬农化工股份有限公司 | Synthetic process of herbicide dicamba |
| WO2015049360A1 (en) * | 2013-10-04 | 2015-04-09 | Basf Se | Selective hydrolysis and alcoholysis of chlorinated benzenes |
| CN103819307A (en) * | 2014-02-12 | 2014-05-28 | 葫芦岛锦化化工工程设计有限公司 | Method for preparing chlorobenzene, p-dichlorobenzene and o-dichlorobenzene in benzene chlorination |
Non-Patent Citations (1)
| Title |
|---|
| 孟明扬等: "3，6-二氯水杨酸的合成", 《精细与专用化学品》 * |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN109096099A (en) * | 2018-09-28 | 2018-12-28 | 萧县新秀新材料有限公司 | The production method of 3,5- di-tert-butyl-4-hydroxybenzoic acid |
| CN109096099B (en) * | 2018-09-28 | 2021-01-12 | 萧县新秀新材料有限公司 | Production method of 3, 5-di-tert-butyl-4-hydroxybenzoic acid |
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