CN102442906B

CN102442906B - Technology for producing low chroma acetyl-tri-n-butyl citrate by using concentrated sulfuric acid as catalyst

Info

Publication number: CN102442906B
Application number: CN201110378014.3A
Authority: CN
Inventors: 冯勇; 张建根
Original assignee: NANTONG ADVANCE CHEMICALS CO Ltd
Current assignee: Qidong Qiangqiang Trade Co ltd
Priority date: 2011-11-24
Filing date: 2011-11-24
Publication date: 2015-03-25
Anticipated expiration: 2031-11-24
Also published as: CN102442906A

Abstract

The invention discloses a technology for producing low chroma acetyl-tri-n-butyl citrate by using concentrated sulfuric acid as a catalyst, comprising the steps of esterification, dealcoholization, washing, drying, filtration, acetylation, deacidification, washing, drying, and filtration. The technology solves the disadvantages that when using traditional concentrated sulfuric acid as the catalyst to synthesize tri-n-butyl citrate and acetyl-tri-n-butyl citrate, the by-product is excessive, the color is deep, the yield is low, and the chroma is reduced after carrying out decoloration many times. The technology comprises the following steps: adding soda ash in the reaction to convert sulfuric acid into sodium bisulfate, then carrying out vacuum dealcoholization, after acetylation of TBC, directly carrying out underpressure distillation on acetate, then washing and drying to obtain a qualified acetyl-tri-n-butyl citrate product. According to the technology, the synthesis of acetyl-tri-n-butyl citrate by using the cheap catalyst can be accomplished without special medicaments and special equipments.

Description

Take the vitriol oil as the technique of the low colourity ATBC of Catalyst Production

Technical field

The present invention relates to the synthetic method of ATBC ATBC and homologue thereof, particularly do the synthetic method of catalyzer synthetic environment-friendly high-purity acetyl tri-n-butyl citrate ATBC with the vitriol oil, belong to environment-friendly plasticizer production.

Background technology

Softening agent is also known as fluidizer, its Main Function weakens the Van der Waals force between polymer molecule, thus add the movability of polymer molecular chain, reduce the crystallinity of polymer molecular chain, add the plasticity of polymkeric substance, show as the hardness of polymkeric substance, modulus, softening temperature and embrittlement temperature to decline, and elongation, flexibility and snappiness improve.

Traditional plasticizer DOP, DBP, DEHP etc. all have carinogenicity, make again people's anaemia, blood urine, hepatopathy, may cause the entanglement of child's sex, endanger male reproductive function, impel the harm such as female precocious puberty and leucocytes reduction.In May, 2011, the fluidizer disturbance in Taiwan pushed the harm of traditional fluidizer to peak.Tributyl O-acetylcitrate is as a kind of non-toxic plasticizer; prove through using; complete energy replaces traditional phthalic ester plasticizer, is used for the aspects such as food product pack, medical apparatus, toy for children, personal hygiene article by FDA Food and Drug Administration's approval.ATBC is as primary plasticizer, and have solvability strong, oil-proofness, photostabilization are good, and have good mould resistance.It and most of Mierocrystalline cellulose, polyvinyl chloride, polyvinyl acetate (PVA) etc. have good consistency, the main softening agent being used as celluosic resin and Vinylite.In toy for children, along with being constantly found of DOP toxicity data, more and more field prohibits the use DOP, and ATBC is nontoxic, tasteless, the transparency is good, water sucrose extraction is low, plastics processing characteristics through its plasticising is excellent, heat sealer is good, and secondary processing is convenient, is particularly suitable as toy for children primary plasticizer and uses.In packaging of meat products, ATBC is nontoxic, can be used as packaging of meat products material, and DOP can not be applied in high fat content food packaging applications.And ATBC is tasteless, can not cause food peculiar smell, the plastics through its plasticising are transparent, and printing performance is good.In medical product, ATBC is nontoxic, and water sucrose extraction is low, does not have potential hazard to human body, and the medical product through its plasticising is high temperature resistant, low-temperature performance good.ATBC not only meets the condition of non-toxic plasticizer as a kind of excellent softening agent, also can be used in general plastics.Low with the Mierocrystalline cellulose cinefilm devolatilization of ATBC plasticizing, compared with the Mierocrystalline cellulose cinefilm containing DBP, there is stronger adhewsive action to metal.China is plastic prod big export country, the epoch of green chemical industry are greatly developed in the whole world, have a very wide range of applications prospect at home and in the world, many developed countries strengthen the R & D and manufacture application of this respect very early, the domestic research in recent years also increased it, key is to select the most suitable catalyzer of two-step reaction.

Synthesis of acetyl tri-n-butyl citrate ATBC, mainly contains the method for following several catalyzer synthesis: 1, the vitriol oil makees catalyzer at present, high dehydrated mainly due to the vitriol oil, and cause by product in reaction process more, productive rate is not high, and product color is darker; 2, superpower solid acid catalysis method, expensive due to solid acid, the large catalyst recovery difficulty of consumption, cost is high, unrealistic in the industrial production; 3, Catalyzed by p-Toluenesulfonic Acid method, as number of patent application in 200810025190.7 the method that proposes, when the ratio of alkyd amount of substance is excessive, big energy-consuming, plant factor is low; 4, inorganic salt catalysis method, as number of patent application in 200510050433.9 the method that proposes, catalyzer usage quantity is large, or costly, is not suitable for industrial production; 5, heteropoly acid catalysis method, shortcoming is catalyst recovery difficulty, and consumption is large, expensive catalyst, needs a large amount of equipment to participate in reaction; 6, nano-oxide catalysis method, shortcoming is also because catalyzer is expensive, and consumption is large, is difficult to the shortcomings such as recycling and hinders application; 7, exchange resin method, this method is easy to be separated, and aftertreatment is simple, but long reaction time, esterification yield is low; 8, microwave irradiation, feature is, the fast 3-12 of speed of response times, but productive rate is low.These synthetic methods are all further improved, and wherein use sulphate method, and cost is minimum, if it is more to overcome by product, the problems such as productive rate is not high, and product color is darker, have a very big significance for industrial production.

Summary of the invention

The main innovative point of the present invention be solve with the vitriol oil be catalyzer synthesis of acetyl tri-n-butyl citrate ATBC process in, the problems such as by product is more, and productive rate is not high, and product color is darker.The technique improved can be catalyzer synthetic environment-friendly high-purity acetyl tri-n-butyl citrate ATBC with the vitriol oil, provides the method solving FAQs.Reach and improve plant factor and product yield, reduce by product, reduce product color, reduce the object of product cost.

In order to achieve the above object, the present invention adopts following technical scheme:

The synthesis technique of ATBC ATBC of the present invention comprises the following steps:

1. esterification: propyl carbinol, citric acid, the vitriol oil are joined in reactor successively according to the ratio of the amount of substance of 6-1: 1: 0.001-0.05 and refluxes, carry out esterification, when being warmed up to 110-150 DEG C, stopped reaction obtains tri-n-butyl citrate crude product;

2. dealcoholysis: tri-n-butyl citrate crude product is cooled to 50-100 DEG C, add the alkali that quality is vitriol oil quality 50-95%, the catalyst neutralisation vitriol oil and remaining citric acid, heat up, vacuumize and carry out dealcoholysis, dealcoholysis temperature controls between 90-160 DEG C, the alcohol that last inflated with nitrogen removing is remaining, controls nitrogen flow between 0.5-50L/min;

3. wash: after the tri-n-butyl citrate cool to room temperature after dealcoholysis, add water, add alkali, add the alkali that quality is the 2-5% of tri-n-butyl citrate quality, the vitriol oil that neutralization is remaining and citric acid, adjustment pH is 7-13, control washing temperature 10-90 DEG C, stir 10-50min, leave standstill separatory, get the organic phase of tri-n-butyl citrate, isolated tri-n-butyl citrate is carried out drying;

4. dry and filtration: in drying process, reactor vacuumizes, inflated with nitrogen, and control nitrogen flow 0.5-50L/min, control dry top temperature 90-190 DEG C, filter: drying completes, control the remaining temperature of material at 90-150 DEG C, obtain dry tri-n-butyl citrate product;

5. acetylize: tri-n-butyl citrate and diacetyl oxide are added diacetyl oxide by the ratio of the amount of substance of 1: 1-1.35, stir 5-50min, adding quality is that the vitriol oil of the 1-2% of diacetyl oxide quality carries out acetylization reaction, control temperature is between 50-130 DEG C, insulation 1-3h, obtains ATBC crude product;

6. depickling: add the water that quality is the 5-55% of acid anhydrides quality, heat up gradually, control negative pressure, nitrogen flow controls at 10-50L/min, and depickling temperature controls between 100-180 DEG C;

7. repeat the process of 4, obtain the ATBC that purity is higher.

Wherein, after described esterification completes, add the alkali catalyst neutralisation vitriol oil, the vitriol oil is avoided to be dewatered by tri-n-butyl citrate carbonization, can ensure the colourity of ATBC finished product, and selected alkali is soda ash, its objective is the too fast heat release in order to avoid neutralization reaction, increase reaction safety; Waste water after tri-n-butyl citrate washing is recyclable, uses when next time washs.This technique is suitable for the long-chain saturated alcohol being greater than four carbon equally, C _nh _2nas amylalcohol, hexanol, octanol etc., be suitable for the many carbonic anhydrides being greater than two carbon too, R-CO-O-CO-R, wherein R is organic group to OH (n > 4).

The present invention can realize cheap catalyst synthesis of acetyl tri-n-butyl citrate and complete under the condition without the need to extraordinary medicament and special equipment.

Accompanying drawing explanation

Fig. 1 is process flow sheet of the present invention.

Embodiment

Embodiment 1

First at 6m ³reactor in add propyl carbinol 2350kg, limit stir, while the citric acid 1000kg that feeds intake.After citric acid has fed intake, and add vitriol oil 55kg, start persistently overheating, timing from being warmed up to 100 DEG C, in about 2 hours, control temperature is at 110-135 DEG C.Note backflow.When the volume collecting water reaches theoretical value, cool to 80 DEG C, open reaction kettle cover, add 50kg soda ash, cover reaction kettle cover, heat up decompression dealcoholysis, and control temperature is below 155 DEG C, and finally controlling nitrogen flow is the alcohol that the removing of 20L/min inflated with nitrogen remains.Cool to room temperature and add 2 tons, water, in whipping process, add 35kg soda ash, adjust ph, about 8, water-washes away unreacted citric acid and catalyzer, and does not distill propyl carbinol completely.After separatory, dehydrate, filter with plate type pressure filter, tri-n-butyl citrate (TBC) product that colourity is No. 120 (platinum-cobalt method) left and right can be obtained.TBC is driven in acetylize still; add 630kg diacetyl oxide; add the 10kg vitriol oil; control between acetylize temperature 65 DEG C-105 DEG C; be incubated 2 hours, then add 35kg water, heat up; start depickling; control depickling top temperature 135 DEG C, after cooling to room temperature, add water; pH is adjusted to be about 8; wash 1 to 2 times, after separatory, dehydrate and control top temperature not higher than 125 DEG C; then heat filtering, obtains ATBC (ATBC) the product 1901kg that colourity is No. 80 (platinum-cobalt method).Yield: 99.3%, gas chromatographic analysis ATBC content 99.5%.

Embodiment 2

First at 6m ³reactor in add propyl carbinol 2150kg, limit stir, while the citric acid 1000kg that feeds intake.After citric acid has fed intake, and add vitriol oil 45kg, start persistently overheating, timing from being warmed up to 100 DEG C, in about 2 hours, control temperature is at 120-130 DEG C.Note backflow.When reaching theoretical value to the volume collecting water, cool to 60 DEG C, open reaction kettle cover, add 30kg soda ash, cover reaction kettle cover, heat up decompression dealcoholysis, and control temperature is below 150 DEG C, and last nitrogen flow is the alcohol that the removing of 30L/min inflated with nitrogen remains.Cool to room temperature and add 2.5 tons, water, in whipping process, add 30kg soda ash, adjust ph, about 8, water-washes away catalyzer and unreacted citric acid, and does not distill propyl carbinol completely.After separatory, dehydrate, filter with plate type pressure filter, tri-n-butyl citrate (TBC) product that colourity is No. 80 (platinum-cobalt method) left and right can be obtained.TBC is driven in acetylize still; add 630kg diacetyl oxide; add the 10kg vitriol oil; control between acetylize temperature 65 DEG C-90 DEG C; be incubated 2.5 hours, then add 55kg water, heat up; start depickling; control depickling top temperature 140 DEG C, after cooling to room temperature, add water; pH is adjusted to be about 8; wash 1 to 2 times, after separatory, dehydrate and control top temperature not higher than 125 DEG C; then heat filtering, obtains ATBC (ATBC) the product 1890kg that colourity is No. 60 (platinum-cobalt method).Yield: 98.7%, gas chromatographic analysis ATBC content 99.1%.

Embodiment 3

First at 6m ³reactor in add propyl carbinol 2000kg, limit stir, while the citric acid 1000kg that feeds intake.After citric acid has fed intake, and add vitriol oil 45kg, start persistently overheating, timing from being warmed up to 100 DEG C, in about 2 hours, control temperature is at 125-140 DEG C.Note backflow.When reaching theoretical value to the volume collecting water, cool to 55 DEG C, open reaction kettle cover, add 40kg soda ash, cover reaction kettle cover, heat up decompression dealcoholysis, and control temperature is below 155 DEG C, and last nitrogen flow is the alcohol that the removing of 15L/min inflated with nitrogen remains.Cool to room temperature and add 2.5 tons, water, in whipping process, add 32kg soda ash, adjust ph, about 8, water-washes away catalyzer and unreacted citric acid, and does not distill propyl carbinol completely.After separatory, dehydrate, filter with plate type pressure filter, obtain tri-n-butyl citrate (TBC) product that colourity is No. 100 (platinum-cobalt method) left and right.TBC is driven in acetylize still; add 600kg diacetyl oxide; add the 12kg vitriol oil; control between acetylize temperature 85 DEG C-110 DEG C; be incubated 3.5 hours, then add 65kg water, heat up; start depickling; control depickling top temperature 130 DEG C, after cooling to room temperature, add water; pH is adjusted to be about 8; wash 1 to 2 times, after separatory, dehydrate and control top temperature not higher than 125 DEG C; then heat filtering, obtains ATBC (ATBC) the product 1851kg that colourity is No. 80 (platinum-cobalt method).Yield: 96.7%, gas chromatographic analysis ATBC content 98.2%.

Embodiment 4

First at 6m ³reactor in add propyl carbinol 2150kg, limit stir, while the citric acid 1000kg that feeds intake.After citric acid has fed intake, and add vitriol oil 40kg, start persistently overheating, timing from being warmed up to 100 DEG C, in about 2 hours, control temperature is at 115-140 DEG C.Note backflow.When reaching theoretical value to the volume collecting water, cool to 70 DEG C, open reaction kettle cover, add 30kg soda ash, cover reaction kettle cover, heat up decompression dealcoholysis, and control temperature is below 140 DEG C, and most nitrogen flow is the alcohol that after 40L/min, inflated with nitrogen removing is residual.Cool to room temperature and add 2.5 tons, water, in whipping process, add 28kg soda ash, adjust ph, about 8, water-washes away unreacted citric acid and catalyzer, and does not distill propyl carbinol completely.After separatory, dehydrate, filter with plate type pressure filter, the TBC product that colourity is No. 100 (platinum-cobalt method) left and right can be obtained.Tri-n-butyl citrate (TBC) is driven in acetylize still; add 610kg diacetyl oxide; add the 6kg vitriol oil; control between acetylize temperature 65 DEG C-95 DEG C; be incubated 2 hours, then add 65kg water, heat up; start depickling; control depickling top temperature 140 DEG C, after cooling to room temperature, add water; pH is adjusted to be about 8; wash 1 to 2 times, after separatory, dehydrate and control top temperature not higher than 130 DEG C; then heat filtering, obtains ATBC (ATBC) the product 1863kg that colourity is No. 60 (platinum-cobalt method).Yield: 97.3%, gas chromatographic analysis ATBC content 98.6%.

Embodiment 5

First at 5m ³reactor in add propyl carbinol 2150kg, limit stir, while the citric acid 1200kg that feeds intake.After citric acid has fed intake, and add vitriol oil 50kg, start persistently overheating, timing from being warmed up to 100 DEG C, in about 2 hours, control temperature is at 110-130 DEG C.Note backflow.When reaching theoretical value to the volume collecting water, cool to 65 DEG C, open reaction kettle cover, add 30kg soda ash, cover reaction kettle cover, heat up decompression dealcoholysis, and control temperature is below 140 DEG C, and last nitrogen flow is the alcohol that the removing of 35L/min inflated with nitrogen remains.Cool to room temperature and add 2.5 tons, water, in whipping process, add 25kg soda ash, adjust ph, about 8, water-washes away unreacted citric acid and catalyzer, and does not distill propyl carbinol completely.After separatory, dehydrate, filter with plate type pressure filter, tri-n-butyl citrate (TBC) product that colourity is No. 80 (platinum-cobalt method) left and right can be obtained.TBC is driven in acetylize still; add 670kg diacetyl oxide; add the 12kg vitriol oil; control between acetylize temperature 65 DEG C-90 DEG C; be incubated 2.5 hours, then add 80kg water, heat up; start depickling; control depickling top temperature 138 DEG C, after cooling to room temperature, add water; pH is adjusted to be about 8; wash 1 to 2 times, after separatory, dehydrate and control top temperature not higher than 130 DEG C; then heat filtering, obtains ATBC (ATBC) the product 2215kg that colourity is No. 60 (platinum-cobalt method).Yield: 96.4%, gas chromatographic analysis ATBC content 97.9%.

Claims

1. be the technique of the low colourity ATBC of Catalyst Production with the vitriol oil, it is characterized in that, it comprises the following steps:

A. esterification: by propyl carbinol, citric acid, the vitriol oil joins in reactor successively according to the ratio of the amount of substance of 6-1: 1: 0.001-0.05 and refluxes, and carries out esterification, and when being warmed up to 110-150 DEG C, stopped reaction obtains tri-n-butyl citrate crude product,

B. dealcoholysis: tri-n-butyl citrate crude product is cooled to 50-100 DEG C, add the alkali that quality is vitriol oil quality 50-95%, the catalyst neutralisation vitriol oil and unreacted citric acid, then heat up, vacuumize, carry out dealcoholysis, dealcoholysis temperature controls between 90-160 DEG C, the alcohol that last inflated with nitrogen removing is remaining, control nitrogen flow between 0.5-50L/min

C. washing, dry and filtration: after the cool to room temperature after dealcoholysis, add water, add the alkali that quality is tri-n-butyl citrate quality 2-5%, the vitriol oil that neutralization is remaining and citric acid, adjustment pH is 7-13, controls washing temperature 10-90 DEG C, stirs 10-50min, leave standstill separatory, get the organic phase containing tri-n-butyl citrate; Isolated tri-n-butyl citrate is carried out drying, and in drying process, reactor vacuumizes, inflated with nitrogen, and control nitrogen flow 0.5-50L/min, control drying temperature at 90 DEG C-190 DEG C, finally filter with plate type pressure filter, obtain dry tri-n-butyl citrate product

D. acetylize: tri-n-butyl citrate and diacetyl oxide are added diacetyl oxide by the ratio of the amount of substance of 1: 1-2; stir 5-50min; adding quality is that the vitriol oil of diacetyl oxide quality 1-5% carries out acetylization reaction; between control temperature 30-130 DEG C; insulation 2-4h; obtain ATBC crude product

E. depickling: add the water that quality is the 5-55% of acid anhydrides quality, heat up gradually, controls negative pressure, and control nitrogen flow between 0.5-50L/min, depickling temperature controls between 100-180 DEG C,

F. repeat the process of C, obtain the ATBC that purity is higher,

Alkali added in described B and step C is solid soda ash.

2. be the technique of the low colourity ATBC of Catalyst Production according to claim 1 with the vitriol oil, it is characterized in that, described step A is fed intake successively by the ratio of the amount of substance of 6-1: 1: 0.001-0.03 at propyl carbinol, citric acid, the vitriol oil, slow intensification, temperature starts timing after rising to 100 DEG C, at 110-140 DEG C of inside holding 2h.

3. be the technique of the low colourity ATBC of Catalyst Production according to claim 1 with the vitriol oil, it is characterized in that, the pH value range in described step C is between 7-11, and washing temperature is between 30-90 DEG C, and churning time is between 20-50min.

4. be the technique of the low colourity ATBC of Catalyst Production according to claim 1 with the vitriol oil, it is characterized in that, the nitrogen flow in described step C is between 5-50L/min, and drying temperature is between 90-150 DEG C.

5. be the technique of the low colourity ATBC of Catalyst Production according to claim 1 with the vitriol oil, it is characterized in that, described D step is fed intake successively by the ratio of 1: 1-1.35 amount of substance at tri-n-butyl citrate and diacetyl oxide, stir 15-50min, add the vitriol oil that quality is diacetyl oxide quality 1-3%, control temperature, between 50 DEG C-130 DEG C, is incubated 1.5-4h.

6. be the technique of the low colourity ATBC of Catalyst Production according to claim 1 with the vitriol oil, it is characterized in that, the quality of the water added in described E step is the 20-55% of acid anhydrides quality, depickling temperature is between 100-165 DEG C, and nitrogen flow controls between 10-50L/min.