CN106278884A - The processing technique of DOTP - Google Patents
The processing technique of DOTP Download PDFInfo
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- CN106278884A CN106278884A CN201610698212.0A CN201610698212A CN106278884A CN 106278884 A CN106278884 A CN 106278884A CN 201610698212 A CN201610698212 A CN 201610698212A CN 106278884 A CN106278884 A CN 106278884A
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/08—Preparation of carboxylic acid esters by reacting carboxylic acids or symmetrical anhydrides with the hydroxy or O-metal group of organic compounds
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/52—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation
- C07C67/54—Separation; Purification; Stabilisation; Use of additives by change in the physical state, e.g. crystallisation by distillation
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- C—CHEMISTRY; METALLURGY
- C07—ORGANIC CHEMISTRY
- C07C—ACYCLIC OR CARBOCYCLIC COMPOUNDS
- C07C67/00—Preparation of carboxylic acid esters
- C07C67/48—Separation; Purification; Stabilisation; Use of additives
- C07C67/56—Separation; Purification; Stabilisation; Use of additives by solid-liquid treatment; by chemisorption
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- Chemical & Material Sciences (AREA)
- Organic Chemistry (AREA)
- Crystallography & Structural Chemistry (AREA)
- Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
- Low-Molecular Organic Synthesis Reactions Using Catalysts (AREA)
Abstract
nullThe invention discloses the processing technique of a kind of DOTP，It comprises the following steps: 1. with weight ratio as 1:2～the p-phthalic acid of 3 and isooctanol are as main material，At normal pressure、Esterification is carried out at 120～230 DEG C，After reacting 8 10h，It is warming up to 225～235 DEG C，And add tetraisopropyl titanate catalyst，The amount of catalyst is the 0.05 ‰ of the amount sum of main material，Reaction obtains head product，2. head product is carried out vacuum flashing process，3. toward step 2. in head product add sodium carbonate liquor reaction 10min after，The 15min that persistently adds water washes，Draining after precipitation 40min，4. head product is after acidity adjustment，Being passed through water in reactor makes it vaporize and alcohol excess formation azeotropic mixture，Discharge after condensed，Carry out dealcoholation treatment，5. eventually pass filter and obtain DOTP finished product.Present invention process condition is simple, quality of finished is high, course of reaction environmental protection.
Description
Technical field
The invention belongs to plasticizer processing method technical field, the processing work of a kind of DOTP
Skill.
Background technology
DOTP (DOTP) is the primary plasticizer of a kind of excellent performance, it and the most conventional O-phthalic
Acid di-isooctyl (DOP) is compared, and has the advantages such as volatilization heat-resisting, cold-resistant, difficult, anti-extraction, flexibility and electrical insulation capability are good,
Goods demonstrate excellent persistency, resistance to soap aqueous and low-temperature pliability, therefore it is of wide application.Such as, wave because of it
Sending out property low, DOTP can fully meet electric wire temperature resistant grade requirement, can be applicable to resistance to 70 ° of C CABLE MATERIALS (International Electrotechnical Commissions
IEC standard) and other various PVC flexible articles in；The most such as, because it has excellent intermiscibility, DOTP also can be as plasticising
Agent is applied to acrylic nitrile derivates, in polyvinyl butyral resin, nitrile rubber, celluloid etc.；Additionally, DOTP is alternatively arranged as
Plasticizer is used for synthetic rubber, as coating additive, precision instrument lubricant, lubricant additive, the softening agent etc. of paper
Use.
At present, the production of DOTP has following several technique: direct esterification production technology: by p-phthalic acid and isooctanol
Under catalyst action, direct esterification forms, and wherein, catalyst uses metal-oxide, both sexes catalyst, or esters catalyst etc..The
Two kinds of production methods are ester-interchange method production technologies: entered under catalyst action by terephthalate or polyester terephthalate
Row ester exchange.In above-mentioned production technology, the catalyst price that it uses is high, and reaction condition is required height, is unfavorable for environmental protection
And heavy industrialization carries out.
Summary of the invention
In order to overcome the deficiencies in the prior art, the invention provides the processing technique of a kind of DOTP, should
The advantage such as processing technique has that process conditions are simple, quality of finished is high, course of reaction environmental protection, cost are relatively low.
To achieve these goals, the technical solution used in the present invention is: the processing work of a kind of DOTP
Skill, it is characterised in that comprise the following steps: 1. esterification, with weight ratio as 1:2～the p-phthalic acid of 3 and isooctanol are
Main material, adds in reactor, carries out the esterification without catalyst in normal pressure, at 120～230 DEG C, after reaction 8-10h, and liter
Temperature is to 225～235 DEG C, and adds tetraisopropyl titanate catalyst, and the amount of catalyst is the 0.05 ‰ of the amount sum of main material, instead
Should complete to obtain DOTP head product, 2. head product be carried out vacuum flashing process, by reactor evacuation, very
Reciprocal of duty cycle >=-0.085Mpa, 3. carries out acidity adjustment by the head product processed through flash distillation, by step 2. in head product add carbon
After acid sodium solution reaction 10min, the 15min that persistently adds water washes, and draining after precipitation 40min, 4. head product is adjusted through acidity
After joint, it is passed through on reactor still top after water makes it vaporize and forms azeotropic mixture with alcohol excess, condensed rear discharge, carry out at dealcoholysis
Reason, is 5. filtrated to get DOTP finished product by the head product after dealcoholysis through filter.
Further, the amount of described sodium carbonate liquor is the 0.6～0.9 ‰～0.9 ‰ of thick product volume.
Further, amount is step 1. middle head product amount the 4～4.5 ‰ ‰ of described step 3. middle addition water.
Further, described step 4. at liquid temperature 150～190 DEG C dry blowing 20min after water flowing 80min.
Further, described water flowing speed is 240～800L/h.
Further, described step 3. in also include drop color process, after head product is cooled to 85～95 DEG C, add
Activated carbon carries out dropping color and processes, and the dehydration that heats up after having processed is to body electricity >=1.0 × 1012Ω·cm。
Further, described isooctanol puts in three times, and liquid temperature≤110 DEG C during first input, secondary adds alcohol liquid temperature 200
DEG C, add alcohol liquid temperature 215 DEG C for three times.
Further, described step 1. in, when liquid temperature is 175～180 DEG C, add catalyst.
Further, flash-point >=210 DEG C of described head product after 4. step processes, acid number≤0.02 mgKOH/
g。
Use such scheme, step of the present invention 1. in esterification, use two steps to complete, the first step: p-phthalic acid
Generating p-phthalic acid mono octyl ester with capryl alcohol reaction, this step reaction need not can carry out under catalyst action, but relatively slow,
Mainly solid-liquid reaction reason, temperature is reacted when 120 ~ 230 DEG C and can be basically completed.Second step: p-phthalic acid mono octyl ester
Generating DOTP and water with capryl alcohol reaction, this step reaction needs at Cat(C12H28O4Ti) phthalandione four isopropyl ester is made
Carrying out under with, reaction liquid temperature can be basically completed at 225 ~ 235 DEG C, and this reaction is a reversible reaction, for making reaction as early as possible to shape
The direction becoming ester carries out being removed from response system rapidly by the water in reactant, is conducive to improving raw material p-phthalic acid
Utilization rate.Add appropriate phthalandione four isopropyl ester and make Cat, to reduce reaction activity；The alcohol of excess i.e. increases the concentration of reaction alcohol,
Can promote to react the direction to generating ester to carry out, improve p-phthalic acid conversion ratio.Water in alcohol and reaction system is formed altogether
(azeotropic consists of capryl alcohol 20%, water 80%, this composition to utilize the difference of specific gravity of condensed fluid pungent alcohol and water to be gone out by moisture after boiling thing cooling
Under azeotropic point be 99.1 DEG C).Step 2. middle flash distillation is an alcohol, ester separation process, utilizes esterification waste heat, at vacuum condition
Under, by major part alcohol excess abjection in esterification reaction process, to collect in alcohol water collecting tank after condensation, step is 3. middle to be processed
Acid number and fall color, this operation is to neutralize the acid of unreacted monoesters completely, making thick ester acidity qualified, improve finished product color simultaneously
Pool, the processing procedure of destruction catalyst.Primary response is that sodium carbonate is neutralized reaction with unreacted monoesters acid completely；Side reaction
For the saponification of DOTP, in processing procedure, inorganic agent addition is too much, and material is alkalescence, in operation
At a temperature of the saponification of ester can occur, its reaction equation is:
P-phthalic acid mono octyl ester+sodium carbonate+waterP-phthalic acid double sodium salt+sodium bicarbonate+capryl alcohol
This reaction seriously reduces the yield of ester, and causes difficulty (finished product is muddy, is difficult to filter) to rear operation, reduces aqueous alkali
The time of staying in material can be substantially reduced this response speed.So the amount of the sodium carbonate liquor added and response time all need
Through specific control, can not be long or too short；It addition, in order to improve product inherent quality, material adds a certain amount of water
Wash, to wash away the catalyst in material, excessive alkali liquor, impurity.
Head product through flash distillation, neutralize, washing process after, utilize steam distillation principle, be passed through from still top water enter point
Join dish vaporization with in esterification alcohol excess formation azeotropic mixture and steam, condensed after moisture is gone out.For making alcohol excess de-clean,
Operate at a lower temperature, it is ensured that end product quality, therefore take decompression operation.Water flowing is an essential condition of dealcoholysis, intake
Too small alcohol is not de-clean, but intake is crossed conference and affected the content carrying ester in system vacuum and abjection alcohol secretly, is unfavorable for esterification
Color and luster.Therefore, intake is wanted suitably, to ensure normal heat and the system vacuum that dealcoholysis needs.If through above step, produce
Product color and luster is partially deep, can take to be cooled to 85～95 DEG C, adds proper amount of active carbon and carries out dropping color, and the dehydration that then heats up is closed to body electricity
Lattice.
Filter progress is last process that dioctyl ester finished product is refined, by airtight plate filter by post processing finished product
In activated carbon and other mechanical admixture remove prepare finished product, putting in storage.
In a word, in the present invention, esterification forms dibasic acid esters again because being initially formed monoesters, uses terephthaldehyde's excessive acid to have greatly
Amount monoesters exists because alcohol is not enough, and monoesters and dibasic acid esters are difficult to separate, therefore uses alcohol excess.Esterification terminal liquid temperature is 225～235
DEG C, this is because caused by the active temperature height of phthalandione four isopropyl ester catalyst, select higher esterification for accelerating response speed
Liquid temperature.For easy post processing, it is also contemplated that flash distillation can continue to reduce acidity after esterification, therefore select endpoint acid number≤0.05%
(in terms of mgKOH/g).Due to Na in inorganic agent2CO3It is generation OH under having water condition -Play deacidification degree effect, institute later
To use solution form to add, adition process opens stirring, for preventing the generation of water decomposition, saponification, therefore uses big yield, often
Adding under pressure condition, the joining day controls, within 10 minutes, to destroy catalyst simultaneously.Material contains less in benzene due to raw material
Amount impurity, and neutralize salinity, the component such as catalyst is stored among material, and it can have a strong impact on the purity of product, and in next work
Sequence filtration difficulty.Adition process opens stirring, therefore uses and add under big yield, atmospheric pressure state, the joining day control 15 minutes with
In, about water yield 1200kg.Intermittently dealcoholysis is carried out after catalyst is destroyed, so for preventing material acid regurgitation, need to be at thing
Water flowing in the case of feed liquid temperature >=160 DEG C, strips alcohol excess.Early stage alcohol excess is many, therefore the water yield is little, along with alcohol excess is in material
Reducing, the water yield steps up.Last qualified to material flash-point.
The isooctanol that the present invention uses has part to use recovery alcohol, it is achieved resource reclaim recycles, the waste water waste material of discharge
PH between 6～9, environmentally friendly, course of reaction uses the mode that carries out between low temperature, high temperature changing effectively utilize heat
Can, esterification reaction process reacts in two steps, reduces the use of catalyst, through the finished product that above-mentioned steps obtains, its colourity can
Good to reach 30-50, purity can reach 99.0-99.5, density 0.981-0.985, and acid number can reach 0.02-
0.03mgKOH/g, flash-point reaches 210, volume resistance >=1.0 × 1012Ω·cm。
Detailed description of the invention
The processing technique of the specific embodiment DOTP of the present invention, comprises the following steps: 1. esterification,
6800kg p-phthalic acid and the isooctanol of 16500kg is added in a kettle. by weight the amount for 1:2.25, the most different pungent
Having 4650kg in alcohol is to reclaim alcohol, and when adding in reactor, isooctanol puts in three times, liquid temperature 110 DEG C during first input, secondary
Liquid temperature 200 DEG C when adding alcohol, liquid temperature 215 DEG C when adding alcohol three times, after material adds, in normal pressure, carry out at 120～230 DEG C without catalysis
The esterification of agent, after reaction 8h, is warming up to 225～235 DEG C, when liquid temperature is 175～180 DEG C, adds tetraisopropyl titanate
Catalyst 12.2kg, has reacted and has obtained DOTP head product 18000kg,
2. head product is carried out vacuum flashing process, by reactor evacuation, vacuum >=-0.085Mpa,
3. the head product processed through flash distillation is carried out acidity adjustment and fall color process, by step 2. in head product add
10.8kg sodium carbonate liquor, after reaction 10min, the 15min that persistently adds water washes, and the amount adding water is 800kg, precipitation
Draining after 40min, if head product color is partially deep, then after head product being cooled to 85～95 DEG C, adds activated carbon and drops
Color processes, and the dehydration that heats up after having processed is to body electricity >=1.0 × 1012Ω·cm。
4. head product is after acidity adjustment, water flowing 80min, water flowing speed in a kettle. at liquid temperature 150～190 DEG C
It is 240～800L/h, forms azeotropic mixture, condensed rear discharge after then dry blowing 20min makes it vaporize with alcohol excess, carry out dealcoholysis
Process, flash-point >=210 DEG C of the head product obtained, acid number≤0.02 mgKOH/g.
5. the head product after dealcoholysis is filtrated to get DOTP finished product through filter.
In above-mentioned reaction, 1. after esterification, esterification endpoint acid number≤0.05(is in terms of mgKOH/g) 2. dealcoholysis post processing,
Neutralize: acid number≤0.02(is in terms of mgKOH/g)
Dealcoholysis, dehydration: flash-point: >=210 DEG C；Acid number :≤0.02(is in terms of mgKOH/g)
Color and luster :≤40#(Pt-CO)；Body electricity >=1.0 × 1012Ω·cm。
3., after filter progress, the finished product of collection is without charcoal and other soon mechanical admixtures, anhydrous transparent haze-free.
The present invention is not limited to above-mentioned detailed description of the invention, and persons skilled in the art are according to disclosed by the invention interior
Hold, other multiple detailed description of the invention can be used to implement the present invention, or the design structure of every employing present invention and think of
Road, does simple change or change, both falls within protection scope of the present invention.
Claims (9)
1. the processing technique of a DOTP, it is characterised in that comprise the following steps: 1. esterification, with weight
Amount than be p-phthalic acid and the isooctanol of 1:2～3 be main material, add in reactor, carry out in normal pressure, at 120～230 DEG C
Without the esterification of catalyst, after reaction 8-10h, it is warming up to 225～235 DEG C, and adds tetraisopropyl titanate catalyst, catalysis
The amount of agent is the 0.05 ‰ of the amount sum of main material, has reacted and has obtained DOTP head product, 2. by head product
Carry out vacuum flashing process, by reactor evacuation, vacuum >=-0.085Mpa, 3. the head product processed through flash distillation is entered
Row acidity adjustment, by step 2. in head product add sodium carbonate liquor reaction 10min after, the 15min that persistently adds water washes,
Precipitation 40min after draining, 4. head product is after acidity adjustment, be passed through on reactor still top after water makes it vaporize with alcohol excess shape
Become azeotropic mixture, condensed rear discharge, carry out dealcoholation treatment, 5. the head product after dealcoholysis is filtrated to get benzene through filter
Dioctyl phthalate dioctyl ester finished product.
The processing technique of DOTP the most according to claim 1, it is characterised in that: described sodium carbonate liquor
Amount is thick product volume 0.6～0.9 ‰～0.9 ‰.
The processing technique of DOTP the most according to claim 1, it is characterised in that: described step 3. in add
Enter amount is step 1. middle head product amount the 4～4.5 ‰ ‰ of water.
4. according to the processing technique of the DOTP described in claim 1-3 any one, it is characterised in that: described
Step 4. at liquid temperature 150～190 DEG C dry blowing 20min after water flowing 80min.
The processing technique of DOTP the most according to claim 4, it is characterised in that: described water flowing speed is
240～800L/h.
6. according to the processing technique of the DOTP described in claim 1-5 any one, it is characterised in that: described
Step 3. in also include drop color process, after head product is cooled to 85～95 DEG C, add activated carbon carry out drop color process, place
Heat up dehydration to body electricity >=1.0 × 10 after having managed12Ω·cm。
7. according to the processing technique of the DOTP described in claim 1-3 any one, it is characterised in that: described
Isooctanol puts in three times, and liquid temperature≤110 DEG C during first input, secondary adds alcohol liquid temperature 200 DEG C, adds alcohol liquid temperature 215 DEG C for three times.
8. according to the processing technique of the DOTP described in claim 1-3 any one, it is characterised in that: described
Step 1. in, when liquid temperature is 175～180 DEG C, add catalyst.
9. according to the processing technique of the DOTP described in claim 1-3 any one, it is characterised in that: described
Flash-point >=210 DEG C of the head product after 4. step processes, acid number≤0.02 mgKOH/g.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
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| CN201610698212.0A CN106278884A (en) | 2016-08-22 | 2016-08-22 | The processing technique of DOTP |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106946708A (en) * | 2017-04-07 | 2017-07-14 | 苏州安利化工有限公司 | Power-economizing method for plasticizer production |
| CN106995371A (en) * | 2017-05-19 | 2017-08-01 | 佛山市高明晟俊塑料助剂有限公司 | A kind of separation method of DOTP |
| CN110227542A (en) * | 2019-06-11 | 2019-09-13 | 中国林业科学研究院林产化学工业研究所 | A kind of charcoal base titanate catalyst and its preparation method and application |
| CN113354536A (en) * | 2020-03-05 | 2021-09-07 | 王群朋 | Process for producing terephthalic acid esters |
| CN113620803A (en) * | 2021-07-20 | 2021-11-09 | 安徽力天环保科技股份有限公司 | Small test method for DOTP production |
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Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106946708A (en) * | 2017-04-07 | 2017-07-14 | 苏州安利化工有限公司 | Power-economizing method for plasticizer production |
| CN106995371A (en) * | 2017-05-19 | 2017-08-01 | 佛山市高明晟俊塑料助剂有限公司 | A kind of separation method of DOTP |
| CN110227542A (en) * | 2019-06-11 | 2019-09-13 | 中国林业科学研究院林产化学工业研究所 | A kind of charcoal base titanate catalyst and its preparation method and application |
| CN113354536A (en) * | 2020-03-05 | 2021-09-07 | 王群朋 | Process for producing terephthalic acid esters |
| CN113620803A (en) * | 2021-07-20 | 2021-11-09 | 安徽力天环保科技股份有限公司 | Small test method for DOTP production |
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