CN111960943A - Process for producing dioctyl terephthalate by semi-continuous method - Google Patents
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- 238000000034 method Methods 0.000 title claims abstract description 20
- OEIWPNWSDYFMIL-UHFFFAOYSA-N dioctyl benzene-1,4-dicarboxylate Chemical compound CCCCCCCCOC(=O)C1=CC=C(C(=O)OCCCCCCCC)C=C1 OEIWPNWSDYFMIL-UHFFFAOYSA-N 0.000 title claims abstract description 19
- 238000011437 continuous method Methods 0.000 title claims abstract description 10
- 238000005886 esterification reaction Methods 0.000 claims abstract description 64
- 230000032050 esterification Effects 0.000 claims abstract description 37
- KKEYFWRCBNTPAC-UHFFFAOYSA-N Terephthalic acid Chemical compound OC(=O)C1=CC=C(C(O)=O)C=C1 KKEYFWRCBNTPAC-UHFFFAOYSA-N 0.000 claims abstract description 25
- 239000003054 catalyst Substances 0.000 claims abstract description 20
- XLYOFNOQVPJJNP-UHFFFAOYSA-N water Substances O XLYOFNOQVPJJNP-UHFFFAOYSA-N 0.000 claims abstract description 20
- 238000006243 chemical reaction Methods 0.000 claims abstract description 18
- 239000002994 raw material Substances 0.000 claims abstract description 18
- 238000006386 neutralization reaction Methods 0.000 claims abstract description 17
- 238000005406 washing Methods 0.000 claims abstract description 17
- BWDBEAQIHAEVLV-UHFFFAOYSA-N 6-methylheptan-1-ol Chemical compound CC(C)CCCCCO BWDBEAQIHAEVLV-UHFFFAOYSA-N 0.000 claims abstract description 16
- YHWCPXVTRSHPNY-UHFFFAOYSA-N butan-1-olate;titanium(4+) Chemical compound [Ti+4].CCCC[O-].CCCC[O-].CCCC[O-].CCCC[O-] YHWCPXVTRSHPNY-UHFFFAOYSA-N 0.000 claims abstract description 16
- 239000000203 mixture Substances 0.000 claims abstract description 14
- 238000001914 filtration Methods 0.000 claims abstract description 7
- 238000004519 manufacturing process Methods 0.000 claims description 15
- LFQSCWFLJHTTHZ-UHFFFAOYSA-N Ethanol Chemical compound CCO LFQSCWFLJHTTHZ-UHFFFAOYSA-N 0.000 claims description 14
- CDBYLPFSWZWCQE-UHFFFAOYSA-L Sodium Carbonate Chemical compound [Na+].[Na+].[O-]C([O-])=O CDBYLPFSWZWCQE-UHFFFAOYSA-L 0.000 claims description 10
- 238000010924 continuous production Methods 0.000 claims description 10
- 238000003756 stirring Methods 0.000 claims description 8
- OKTJSMMVPCPJKN-UHFFFAOYSA-N Carbon Chemical compound [C] OKTJSMMVPCPJKN-UHFFFAOYSA-N 0.000 claims description 7
- 239000002253 acid Substances 0.000 claims description 6
- 150000002148 esters Chemical class 0.000 claims description 6
- 239000000243 solution Substances 0.000 claims description 6
- 239000007864 aqueous solution Substances 0.000 claims description 5
- 238000004821 distillation Methods 0.000 claims description 5
- 239000007789 gas Substances 0.000 claims description 5
- 230000007935 neutral effect Effects 0.000 claims description 5
- 229910000029 sodium carbonate Inorganic materials 0.000 claims description 5
- 239000000126 substance Substances 0.000 claims description 5
- 239000002918 waste heat Substances 0.000 claims description 5
- 238000000926 separation method Methods 0.000 claims description 2
- BJAJDJDODCWPNS-UHFFFAOYSA-N dotp Chemical compound O=C1N2CCOC2=NC2=C1SC=C2 BJAJDJDODCWPNS-UHFFFAOYSA-N 0.000 claims 1
- 230000008901 benefit Effects 0.000 abstract description 4
- 238000012824 chemical production Methods 0.000 abstract description 2
- 238000004042 decolorization Methods 0.000 abstract 1
- KFROBPVFLIZCHZ-UHFFFAOYSA-N bis(6-methylheptyl) benzene-1,4-dicarboxylate Chemical compound CC(C)CCCCCOC(=O)C1=CC=C(C(=O)OCCCCCC(C)C)C=C1 KFROBPVFLIZCHZ-UHFFFAOYSA-N 0.000 description 15
- 239000004014 plasticizer Substances 0.000 description 11
- 238000010438 heat treatment Methods 0.000 description 7
- SIXWIUJQBBANGK-UHFFFAOYSA-N 4-(4-fluorophenyl)-1h-pyrazol-5-amine Chemical compound N1N=CC(C=2C=CC(F)=CC=2)=C1N SIXWIUJQBBANGK-UHFFFAOYSA-N 0.000 description 5
- 238000010923 batch production Methods 0.000 description 3
- 238000009835 boiling Methods 0.000 description 3
- 229910052799 carbon Inorganic materials 0.000 description 3
- 238000005265 energy consumption Methods 0.000 description 3
- 239000007788 liquid Substances 0.000 description 3
- KBPLFHHGFOOTCA-UHFFFAOYSA-N 1-Octanol Chemical compound CCCCCCCCO KBPLFHHGFOOTCA-UHFFFAOYSA-N 0.000 description 2
- ZFMQKOWCDKKBIF-UHFFFAOYSA-N bis(3,5-difluorophenyl)phosphane Chemical compound FC1=CC(F)=CC(PC=2C=C(F)C=C(F)C=2)=C1 ZFMQKOWCDKKBIF-UHFFFAOYSA-N 0.000 description 2
- 230000007547 defect Effects 0.000 description 2
- 230000004048 modification Effects 0.000 description 2
- 238000012986 modification Methods 0.000 description 2
- 230000035484 reaction time Effects 0.000 description 2
- 238000006467 substitution reaction Methods 0.000 description 2
- JNXDCMUUZNIWPQ-UHFFFAOYSA-N trioctyl benzene-1,2,4-tricarboxylate Chemical compound CCCCCCCCOC(=O)C1=CC=C(C(=O)OCCCCCCCC)C(C(=O)OCCCCCCCC)=C1 JNXDCMUUZNIWPQ-UHFFFAOYSA-N 0.000 description 2
- MQIUGAXCHLFZKX-UHFFFAOYSA-N Di-n-octyl phthalate Natural products CCCCCCCCOC(=O)C1=CC=CC=C1C(=O)OCCCCCCCC MQIUGAXCHLFZKX-UHFFFAOYSA-N 0.000 description 1
- 229920002943 EPDM rubber Polymers 0.000 description 1
- 229920000459 Nitrile rubber Polymers 0.000 description 1
- 150000008065 acid anhydrides Chemical class 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
- BJQHLKABXJIVAM-UHFFFAOYSA-N bis(2-ethylhexyl) phthalate Chemical compound CCCCC(CC)COC(=O)C1=CC=CC=C1C(=O)OCC(CC)CCCC BJQHLKABXJIVAM-UHFFFAOYSA-N 0.000 description 1
- 150000005690 diesters Chemical class 0.000 description 1
- 230000000694 effects Effects 0.000 description 1
- 238000003912 environmental pollution Methods 0.000 description 1
- 231100000086 high toxicity Toxicity 0.000 description 1
- 238000009776 industrial production Methods 0.000 description 1
- 238000009413 insulation Methods 0.000 description 1
- -1 isooctyl ester Chemical class 0.000 description 1
- 239000002649 leather substitute Substances 0.000 description 1
- 239000000463 material Substances 0.000 description 1
- 239000003960 organic solvent Substances 0.000 description 1
- 229920003023 plastic Polymers 0.000 description 1
- 239000004033 plastic Substances 0.000 description 1
- 229920001084 poly(chloroprene) Polymers 0.000 description 1
- 230000036632 reaction speed Effects 0.000 description 1
- 238000001179 sorption measurement Methods 0.000 description 1
- 230000002194 synthesizing effect Effects 0.000 description 1
- 238000004065 wastewater treatment Methods 0.000 description 1
Classifications
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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
-
- 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
-
- 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
-
- 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
-
- 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
- C07C67/58—Separation; Purification; Stabilisation; Use of additives by liquid-liquid treatment
Landscapes
- 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
The invention discloses a process for producing dioctyl terephthalate by a semi-continuous method in the technical field of chemical production, which sequentially comprises the following steps: carrying out batch esterification reaction in two esterification kettles, carrying out mono-esterification reaction on terephthalic acid and isooctyl alcohol serving as raw materials and a catalyst tetrabutyl titanate in a first esterification kettle, adding a mixture obtained after the reaction into a second esterification kettle in batches, and simultaneously adding the catalyst tetrabutyl titanate to carry out double-esterification reaction; then the obtained mixture is continuously subjected to neutralization water washing, dealcoholization stripping, decolorization and filtration to obtain the dioctyl terephthalate. The invention not only improves the automation degree, the product quality and the labor productivity, but also saves the time. Has the advantages of stable product quality, low labor intensity, high economic benefit and the like.
Description
Technical Field
The invention relates to a process for producing dioctyl terephthalate, in particular to a process for producing dioctyl terephthalate by adopting a terephthalic acid and isooctyl ester semi-continuous method. Belongs to the technical field of chemical production.
Background
At present, the plasticizers in the world are over ten types, the total amount of the plasticizers is over 500 varieties, the annual total yield is over 500 ten thousand tons, more than 70 percent of the plasticizers are phthalic esters, wherein diisooctyl phthalate (DOP) has good performance, but because DOP pollutes the environment and has high toxicity, the plasticizers are forbidden to be exported by a plurality of European Union countries, and the abuse of the plasticizers is forbidden in China.
The diisooctyl terephthalate (DOTP) plasticizer has good electrical and thermal properties, can replace DOP in a PVC plastic electric wire sheath, and can also be used for producing artificial leather films. In addition, DOTP has excellent compatibility, plays a role in improving the hardness and deformability of products, and can be used as a softener in products such as nitrile rubber, chloroprene rubber, ethylene propylene diene rubber and the like. The plasticizer has good plasticizing effect and low volatility, is widely used for various products requiring heat resistance and high insulation, and is an ideal plasticizer for producing cable materials with temperature resistance of 70 ℃ and other PVC products requiring volatilization resistance.
Most plasticizers such as dioctyl phthalate (DOP), trioctyl trimellitate (TOTM), dioctyl adipate (DOA) and the like are homogeneous in esterification reaction (namely, the used acid anhydride and alcohol are mutually soluble at a lower temperature), so that the reaction speed is higher and the esterification reaction time is short. The esterification reaction of dioctyl terephthalate is different from other types of plasticizers, solid-liquid reaction is firstly carried out in the esterification reaction process, then liquid-liquid homogeneous reaction is carried out, the used acid is most organic solvents such as octanol which are difficult to dissolve in terephthalic acid, the reaction time is long under normal pressure, simultaneously the alcohol circulation amount in the esterification process is large, the temperature is increased by heating again after the dioctyl terephthalate enters an esterification kettle, the production efficiency of products is low, the energy consumption is high, and the development of the production process is limited to a great extent, so that most plasticizer production enterprises adopt an intermittent production process to produce DOTP so far.
The intermittent production process of DOTP in the prior art has the following defects:
(1) the control of the intermittent production process is complex, and the requirements on production conditions are strict, wherein the control variables comprise temperature, liquid level and other control variables;
(2) the intermittent production cycle is long, the energy consumption is large, and the equipment use efficiency is low;
(3) the batch type is only suitable for small-scale production, and the product stability is low.
In the domestic research on the production method of dioctyl terephthalate, although continuous production is mentioned, the related continuous production process is complicated, multiple processes such as esterification, dealcoholization, neutralization and washing, gas stripping, adsorption and filtration, wastewater treatment and the like are included, the used equipment is more, the equipment utilization rate is low, the energy consumption is high, the environmental pollution is high, and the industrial production practice is not met.
Disclosure of Invention
In order to overcome the defects and shortcomings of the existing production process, the invention aims to provide a process for producing dioctyl terephthalate (DOTP) by a semi-continuous method, wherein the DOTP is prepared by the semi-continuous method; the esterification reaction in the previous stage is intermittently produced, and the semi-continuous process mode of continuous production is adopted for subsequent dealcoholization, neutralization and water washing, air stripping and filtration, so that the production is not limited by the esterification reaction in the previous stage, the automation degree is greatly improved, the product quality is stable, the time is saved, the consumption of raw materials and energy sources is low, and the labor productivity is high.
Therefore, the technical scheme of the invention is as follows: a process for producing dioctyl terephthalate by a semi-continuous method sequentially comprises the following steps:
(1) esterification reaction: carrying out esterification reaction by adopting a batch method;
the esterification reaction is carried out in two esterification kettles, in the first esterification kettle, terephthalic acid and isooctyl alcohol are taken as raw materials to carry out the mono-esterification reaction with catalyst tetrabutyl titanate, the mixture after the reaction is added into the second esterification kettle in batches, and simultaneously the catalyst tetrabutyl titanate is added to carry out the di-esterification reaction;
(2) and (2) continuously performing neutralization and water washing, dealcoholization and stripping, decoloring and filtering on the mixture obtained in the step (1) to obtain the dioctyl terephthalate.
In the step (1), in the first esterification kettle, the preheated first esterification kettle is heated to 180 ℃ and 190 ℃, terephthalic acid and isooctanol are added in batches, the molar ratio of acid to alcohol is 1:3-4.5, the addition amount of catalyst tetrabutyl titanate is 0.2-0.3 percent of the total mass of the raw materials, and the raw materials are slowly stirred for 3-4 hours.
In the second esterification kettle, the adding amount of catalyst tetrabutyl titanate is 0.1-0.2% of the total mass of the raw materials, the stirring is continued, the temperature is raised to 220-230 ℃, and the reaction lasts for 2-3 h.
The further improvement is that a gas phase outlet of the second esterification kettle is connected with a condenser and a return pipe, water generated in the esterification reaction and excessive isooctanol form an azeotrope, the azeotrope is evaporated from the gas phase outlet and then subjected to alcohol-water separation by the condenser, and alcohol flows back to enter the esterification kettle to continuously participate in the reaction.
The step (2) can be divided into the following steps:
1) neutralization and water washing: after the esterification reaction is finished, the mixture enters a neutralizer, the temperature is controlled to be 50 +/-5 ℃, the acidity value of the solution is measured, and meanwhile, 4% of sodium carbonate aqueous solution is added for neutralization and water washing to be neutral;
2) dealcoholization and stripping: performing negative pressure dealcoholization on the product after the neutralization and water washing by using waste heat, maintaining the pressure in the tower body to be 1-5Kpa, and removing unreacted isooctanol to enter an esterification kettle for continuously participating in the reaction; continuously adding the dealcoholized product into a stripping kettle, and removing alcohol and odorous low-boiling-point substances in the crude ester by direct steam reduced pressure distillation;
3) and (3) decoloring: continuously adding the dealcoholized product into a decolorizer, and adsorbing and decolorizing by using activated carbon;
4) and (3) filtering: and (4) passing the decolored product through a filter to finally obtain the target product DOTP.
Compared with the prior art, the invention has the beneficial effects that:
compared with the existing batch production process at home and abroad, the reaction of the first esterification kettle mainly generates monoester; the diester generated by the reaction in the second esterification kettle has less reverse reaction and high yield. The production is not limited by the esterification reaction in the early stage, the automation degree is greatly improved, batch reaction and continuous production are considered, and the method has the advantages of stable product quality, time saving, low consumption of raw materials and energy, high labor productivity, low labor intensity, high economic benefit and the like.
Detailed Description
The present invention will be further described with reference to the following examples.
Example 1
A process for producing dioctyl terephthalate by a semi-continuous method takes terephthalic acid and isooctyl alcohol as raw materials, tetrabutyl titanate as a catalyst, and the method for synthesizing the diisooctyl terephthalate by the semi-continuous method comprises the following specific steps:
intermittent production: heating a preheated first esterification kettle to 180 ℃, adding terephthalic acid (PTA) and isooctanol in batches, wherein the molar ratio of acid alcohol is 1:3, the adding amount of catalyst tetrabutyl titanate is 0.2 percent of the total mass of the raw materials, slowly stirring for 3 hours, adding the mixture in the first esterification kettle in batches into a second esterification kettle, simultaneously adding catalyst tetrabutyl titanate, the adding amount of the catalyst is 0.1 percent of the total mass of the raw materials, continuously stirring, heating to 220 ℃, and reacting for 2 hours.
Continuous production: after the esterification reaction is finished, the mixture enters a neutralizer, the temperature is controlled at 45 ℃, the acidity value of the solution is measured, and simultaneously 4% of sodium carbonate aqueous solution is added for neutralization and water washing to be neutral. And then, performing negative pressure dealcoholization on the product after the neutralization and water washing by using waste heat, maintaining the pressure in the tower body to be 5Kpa, and removing unreacted isooctanol to enter an esterification kettle to continuously participate in the reaction. The dealcoholized product is continuously added into a stripping kettle, and alcohol and odorous low-boiling substances in the crude ester are removed by direct steam reduced pressure distillation. And continuously adding the dealcoholized product into a decolorizer, and adsorbing and decolorizing by using active carbon. And (4) passing the decolored product through a filter to finally obtain the target product DOTP.
In this example, the yield of diisooctyl terephthalate was 95%.
Example two
The difference between the present embodiment and the first embodiment is that the batch production: heating a preheated first esterification kettle to 185 ℃, adding terephthalic acid (PTA) and isooctanol in batches, wherein the molar ratio of acid to alcohol is 1:3.5, the adding amount of catalyst tetrabutyl titanate is 0.25 percent of the total mass of the raw materials, slowly stirring for 3.5 hours, adding the mixture in the first esterification kettle in batches into a second esterification kettle, simultaneously adding catalyst tetrabutyl titanate, the adding amount of the catalyst is 0.15 percent of the total mass of the raw materials, continuously stirring, heating to 225 ℃, and reacting for 2.5 hours.
Continuous production: after the esterification reaction is finished, the mixture enters a neutralizer, the temperature is controlled at 50 ℃, the acidity value of the solution is measured, and simultaneously 4% of sodium carbonate aqueous solution is added for neutralization and water washing to be neutral. And then, performing negative pressure dealcoholization on the product after the neutralization and water washing by using waste heat, maintaining the pressure in the tower body to be 3Kpa, and removing unreacted isooctanol to enter an esterification kettle to continuously participate in the reaction. The dealcoholized product is continuously added into a stripping kettle, and alcohol and odorous low-boiling substances in the crude ester are removed by direct steam reduced pressure distillation. And continuously adding the dealcoholized product into a decolorizer, and adsorbing and decolorizing by using active carbon. And (4) passing the decolored product through a filter to finally obtain the target product DOTP.
In this example, the yield of diisooctyl terephthalate was 95.2%.
EXAMPLE III
The difference between the present example and the second example is that the batch production: heating a preheated first esterification kettle to 190 ℃, adding terephthalic acid (PTA) and isooctanol in batches, wherein the molar ratio of acid to alcohol is 1:4.5, the adding amount of catalyst tetrabutyl titanate is 0.3 percent of the total mass of the raw materials, slowly stirring for 4 hours, adding the mixture in the first esterification kettle in batches into a second esterification kettle, simultaneously adding catalyst tetrabutyl titanate, the adding amount of the catalyst is 0.2 percent of the total mass of the raw materials, continuously stirring, heating to 230 ℃, and reacting for 3 hours.
Continuous production: after the esterification reaction is finished, the mixture enters a neutralizer, the temperature is controlled at 55 ℃, the acidity value of the solution is measured, and simultaneously 4% of sodium carbonate aqueous solution is added for neutralization and water washing to be neutral. And then, performing negative pressure dealcoholization on the product after the neutralization and water washing by using waste heat, maintaining the pressure in the tower body to be 1Kpa, and removing unreacted isooctanol to enter an esterification kettle for continuously participating in the reaction. The dealcoholized product is continuously added into a stripping kettle, and alcohol and odorous low-boiling substances in the crude ester are removed by direct steam reduced pressure distillation. And continuously adding the dealcoholized product into a decolorizer, and adsorbing and decolorizing by using active carbon. And (4) passing the decolored product through a filter to finally obtain the target product DOTP.
In this example, the yield of diisooctyl terephthalate was 95.5%.
The present invention is not limited to the above-mentioned embodiments, and based on the technical solutions disclosed in the present invention, those skilled in the art can make some substitutions and modifications to some technical features without creative efforts according to the disclosed technical contents, and these substitutions and modifications are all within the protection scope of the present invention.
Claims (5)
1. The process for producing the dioctyl terephthalate by the semi-continuous method is characterized by sequentially comprising the following steps of:
(1) esterification reaction: carrying out esterification reaction by adopting a batch method;
the esterification reaction is carried out in two esterification kettles, in the first esterification kettle, terephthalic acid and isooctyl alcohol are taken as raw materials to carry out the mono-esterification reaction with catalyst tetrabutyl titanate, the mixture after the reaction is added into the second esterification kettle in batches, and simultaneously the catalyst tetrabutyl titanate is added to carry out the di-esterification reaction;
(2) and (2) continuously performing neutralization and water washing, dealcoholization and stripping, decoloring and filtering on the mixture obtained in the step (1) to obtain the dioctyl terephthalate.
2. The process for producing dioctyl terephthalate according to claim 1, wherein in the step (1), the preheated first esterification kettle is heated to 190 ℃ at 180 ℃, terephthalic acid and isooctanol are added in batches, the molar ratio of acid alcohol is 1:3-4.5, the amount of catalyst tetrabutyl titanate is 0.2-0.3% of the total mass of the raw materials, and the raw materials are slowly stirred for 3-4 h.
3. The semi-continuous process for producing dioctyl terephthalate according to claim 1, wherein in the step (1), the catalyst is added in an amount of 0.1% -0.2% of the total mass of the raw materials in the second esterification kettle, the stirring is continued, and the temperature is raised to 220 ℃ -230 ℃ for reaction for 2-3 h.
4. The process for producing dioctyl terephthalate according to claim 3, wherein the gas phase outlet of the second esterification reactor is connected with a condenser and a return pipe, water produced in the esterification reaction and excess isooctanol form an azeotrope, the azeotrope is distilled out from the gas phase outlet and subjected to alcohol-water separation by the condenser, and the alcohol flows back into the esterification reactor to continue to participate in the reaction.
5. A semi-continuous process for the production of dioctyl terephthalate according to any one of claims 1 to 4, wherein the step (2) is divided into the following substeps:
1) neutralization and water washing: after the esterification reaction is finished, the mixture enters a neutralizer, the temperature is controlled to be 50 +/-5 ℃, the acidity value of the solution is measured, and meanwhile, 4% of sodium carbonate aqueous solution is added for neutralization and water washing to be neutral;
2) dealcoholization and stripping: performing negative pressure dealcoholization on the product after the neutralization and water washing by using waste heat, maintaining the pressure in the tower body to be 1-5Kpa, and removing unreacted isooctanol to enter an esterification kettle for continuously participating in the reaction; continuously adding the dealcoholized product into a stripping kettle, and removing alcohol and odorous low-boiling-point substances in the crude ester by direct steam reduced pressure distillation;
3) and (3) decoloring: continuously adding the dealcoholized product into a decolorizer, and adsorbing and decolorizing by using activated carbon;
4) and (3) filtering: and (4) passing the decolored product through a filter to finally obtain the target product DOTP.
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Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112209824A (en) * | 2020-10-20 | 2021-01-12 | 山东朗晖石油化学股份有限公司 | Production method of citric acid mixed ester |
| CN113233977A (en) * | 2021-05-17 | 2021-08-10 | 江南大学 | Method for homogeneous synthesis of di (2-ethylhexyl) terephthalate |
| TWI740777B (en) * | 2021-01-29 | 2021-09-21 | 南亞塑膠工業股份有限公司 | Method for preparing plasticzer of low migration dioctyl terephthalate |
| 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 |
| CN114276238A (en) * | 2022-01-07 | 2022-04-05 | 济宁长兴塑料助剂有限公司 | Preparation method of diisooctyl terephthalate |
| CN114933534A (en) * | 2022-04-28 | 2022-08-23 | 山东蓝帆化工有限公司 | Continuous esterification production process of diisooctyl terephthalate heterogeneous system |
| CN117486716A (en) * | 2023-12-28 | 2024-02-02 | 天津渤化澳佳永利化工有限责任公司 | DOA production method |
Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101157615A (en) * | 2007-10-31 | 2008-04-09 | 无锡双象化学工业有限公司 | Method for producing plasticizer phthalic acid dinonyl |
| CN101429126A (en) * | 2008-12-22 | 2009-05-13 | 无锡百川化工股份有限公司 | Method for producing trioctyl trimellitate with trimellitic acid |
| CN102295564A (en) * | 2011-07-25 | 2011-12-28 | 浙江庆安化工有限公司 | Continuous production process for DOP (Dioctyl Phthalate) and used equipment |
| CN102701984A (en) * | 2012-05-25 | 2012-10-03 | 安徽香枫新材料有限公司 | Production method of dioctyl terephthalate |
| CN103360253A (en) * | 2012-04-01 | 2013-10-23 | 中国石油化工股份有限公司 | Method for producing dimethyl maleate |
| CN205965826U (en) * | 2016-08-05 | 2017-02-22 | 中国石化仪征化纤有限责任公司 | Two cauldron systems of esterifying of half continuous polymerization device |
| CN108456139A (en) * | 2018-04-09 | 2018-08-28 | 石家庄白龙化工股份有限公司 | A kind of interval catalytic reaction rectification prepares the device and method of dibutyl phthalate |
-
2020
- 2020-08-27 CN CN202010875992.8A patent/CN111960943A/en active Pending
Patent Citations (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN101157615A (en) * | 2007-10-31 | 2008-04-09 | 无锡双象化学工业有限公司 | Method for producing plasticizer phthalic acid dinonyl |
| CN101429126A (en) * | 2008-12-22 | 2009-05-13 | 无锡百川化工股份有限公司 | Method for producing trioctyl trimellitate with trimellitic acid |
| CN102295564A (en) * | 2011-07-25 | 2011-12-28 | 浙江庆安化工有限公司 | Continuous production process for DOP (Dioctyl Phthalate) and used equipment |
| CN103360253A (en) * | 2012-04-01 | 2013-10-23 | 中国石油化工股份有限公司 | Method for producing dimethyl maleate |
| CN102701984A (en) * | 2012-05-25 | 2012-10-03 | 安徽香枫新材料有限公司 | Production method of dioctyl terephthalate |
| CN205965826U (en) * | 2016-08-05 | 2017-02-22 | 中国石化仪征化纤有限责任公司 | Two cauldron systems of esterifying of half continuous polymerization device |
| CN108456139A (en) * | 2018-04-09 | 2018-08-28 | 石家庄白龙化工股份有限公司 | A kind of interval catalytic reaction rectification prepares the device and method of dibutyl phthalate |
Non-Patent Citations (2)
| Title |
|---|
| 石鸣彦等: "酯化法制备1,6-己二酸二甲酯", 《石化技术与应用》 * |
| 黄发荣等: "《高分子材料的循环利用[M]》", 31 December 2000 * |
Cited By (10)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112209824A (en) * | 2020-10-20 | 2021-01-12 | 山东朗晖石油化学股份有限公司 | Production method of citric acid mixed ester |
| TWI740777B (en) * | 2021-01-29 | 2021-09-21 | 南亞塑膠工業股份有限公司 | Method for preparing plasticzer of low migration dioctyl terephthalate |
| CN114805062A (en) * | 2021-01-29 | 2022-07-29 | 南亚塑胶工业股份有限公司 | Preparation method of low-migration-property bis (2-ethylhexyl) terephthalate plasticizer |
| US20220242813A1 (en) * | 2021-01-29 | 2022-08-04 | Nan Ya Plastics Corporation | Method for preparing low migration plasticizer of di-2-ethylhexyl terephthalate |
| US11873278B2 (en) * | 2021-01-29 | 2024-01-16 | Nan Ya Plastics Corporation | Method for preparing low migration plasticizer of di-2-ethylhexyl terephthalate |
| CN113233977A (en) * | 2021-05-17 | 2021-08-10 | 江南大学 | Method for homogeneous synthesis of di (2-ethylhexyl) terephthalate |
| 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 |
| CN114276238A (en) * | 2022-01-07 | 2022-04-05 | 济宁长兴塑料助剂有限公司 | Preparation method of diisooctyl terephthalate |
| CN114933534A (en) * | 2022-04-28 | 2022-08-23 | 山东蓝帆化工有限公司 | Continuous esterification production process of diisooctyl terephthalate heterogeneous system |
| CN117486716A (en) * | 2023-12-28 | 2024-02-02 | 天津渤化澳佳永利化工有限责任公司 | DOA production method |
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