Continuous production device for dibutyl phthalate

Abstract

The utility model relates to the technical field of production of dibutyl phthalate, in particular to a continuous production device of dibutyl phthalate. The dibutyl phthalate continuous production device comprises a reaction kettle and an n-butyl alcohol molecular adsorption tower, the n-butyl alcohol molecular adsorption tower is connected with the reaction kettle through a preheating kettle, the reaction kettle is connected with a washing tank through a neutralizing tank, the washing tank is connected with a rectifying tower through a decolorizing kettle, the reaction kettle is connected with a phase-splitting tower through a condenser, and the phase-splitting tower is connected with a rectifying tower through a condenser. The neutralization tank is connected with the reaction kettle through the distillation tower. According to the device, the preheating kettle coil pipe, the condenser coil pipe, the phthalic anhydride activated carbon adsorption tank and the n-butyl alcohol molecular adsorption tower are matched for use, waste heat generated in the working process of the condenser is used in the preheating kettle, raw materials are preheated, and the production efficiency and the energy utilization rate are greatly improved.

Description

TECHNICAL FIELD

[0001] The utility model relates to the dibutyl phthalate production technical field, concretely is dibutyl phthalate continuous production device. BACKGROUND

[0002] The chemical formula of dibutyl phthalate (DBP) is C 16 H 22 O4, it belongs to ester compound, and the molecular structure is generated by phthalic acid (a binary acid) and two molecules of butanol (n-butanol or isobutyl alcohol) through esterification reaction. The molecular structure contains benzene ring, ester group and other functional groups, and two ester groups are connected at the adjacent position of the benzene ring.

[0003] In the workshop production process, the raw material enters the reaction kettle at normal temperature, and the temperature of the reaction kettle is 140-150 DEG C. With continuous feeding, the temperature of the reaction kettle fluctuates greatly, affecting the normal progress of the reaction. The product after the reaction needs to be washed a lot when passing through the neutralization tank and the water washing tank, and the waste water produced directly enters the sewage treatment device, which not only increases the waste water treatment capacity, but also causes waste of recyclable raw materials such as n-butanol in the waste water, causing economic loss to the enterprise. UTILITY MODEL CONTENTS

[0004] According to the deficiencies in the above prior art, the utility model aims to provide a dibutyl phthalate continuous production device, which uses the waste heat generated in the working process of the condenser for preheating the kettle to preheat the raw material, greatly improves the production efficiency and energy utilization rate, and removes the impurities generated in the conveying process of the raw material through the phthalic anhydride activated carbon adsorption tank and the n-butanol molecular adsorption tower, improving the product quality. Through the cooperation of the recovery tank, the distillation tower and the temporary storage tank, the waste water generated by the neutralization tank and the water washing tank is recovered and treated, and the n-butanol is recovered for production in the reaction kettle, reducing the waste water treatment capacity and improving the raw material utilization rate.

[0005] The utility model is implemented by adopting the following technical solutions:

[0006] The dibutyl phthalate continuous production device comprises a reaction kettle, an n-butanol molecular adsorption tower, the n-butanol molecular adsorption tower is connected with the reaction kettle through a preheating kettle, the reaction kettle is connected with a water washing tank through a neutralization tank, the water washing tank is connected with a rectifying tower through a decoloring kettle, the reaction kettle is connected with a phase separation tower through a condenser, and the neutralization tank is connected with the reaction kettle through a distillation tower.

[0007] The reaction kettle and the preheating kettle are both provided with stirring devices, so the pipelines are all provided with heat preservation layers.

[0008] The inside of the reaction kettle is equipped with a stirring paddle, and the reaction kettle is connected with an o-phthalic anhydride activated carbon adsorption tank.

[0009] The inside of the preheating kettle is equipped with a preheating kettle coil pipe, the inside of the condenser is equipped with a condenser coil pipe, and the condenser coil pipe is connected with the preheating kettle coil pipe through a connecting pipeline.

[0010] The phase separation tower is connected with the reaction kettle through a phase separation tower return pipeline, and the phase separation tower is equipped with an observation port.

[0011] The neutralization tank is connected with the distillation tower through a recovery tank, a neutralization tank waste water collecting pipeline is connected between the neutralization tank and the recovery tank, and the water washing tank is connected with the recovery tank through the water washing tank waste water collecting pipeline.

[0012] The distillation tower is connected with the phase separation tower return pipeline through a temporary storage tank, a filter is arranged between the decoloring kettle and the distillation tower, and a reaction kettle discharge pipeline is arranged between the reaction kettle and the neutralization tank. The filter is a combination of a backwashing filter and a plate and frame filter press.

[0013] The production process is as follows: taking o-phthalic anhydride and n-butanol as main raw materials, under the action of acid catalysts such as sulfuric acid, esterification reaction is carried out at 140-150 DEG C. First, o-phthalic anhydride and n-butanol are added to the reaction kettle according to the molar ratio of 1: (2.2-2.5). The reaction kettle is provided with a stirring device and a heating device. Water is generated during the esterification reaction, in order to make the reaction proceed in the positive direction, the generated water needs to be removed. The azeotropic distillation method is used to remove water from the reaction system by using the azeotrope formed by n-butanol and water (the azeotropic point is about 92.7 DEG C). After the azeotrope is cooled by the condenser, it enters the phase separation tower, and the water phase and the organic phase are separated, and the organic phase (mainly n-butanol) returns to the reaction kettle to continue the reaction. The crude product after the reaction contains acidic catalysts, which needs to be treated by neutralization in the neutralization tank. The neutralizing agent is sodium carbonate or sodium hydroxide solution. The product after neutralization is washed with water in the water washing tank to remove residual salts and unreacted raw materials and other impurities. The product after neutralization and water washing may contain some pigments and a small amount of solid impurities, which need to be treated by adding activated carbon and other decoloring agents in the decoloring kettle. After stirring in the decoloring kettle for a certain period of time, the activated carbon and other solid impurities are removed by the filter to obtain relatively pure dibutyl phthalate product. Then, through the distillation tower, according to the different boiling points of dibutyl phthalate and other impurities (such as a small amount of unreacted n-butanol), further separation and purification are carried out to obtain high-purity product. The recovery tank, the distillation tower and the temporary storage tank are used for recycling the waste water generated by the neutralization tank and the water washing tank, and the recovered n-butanol is used for the production of the reaction kettle; the waste heat generated in the working process of the condenser is used for preheating the raw materials in the preheating kettle.

[0014] Compared with the prior art, the beneficial effects of the utility model are as follows:

[0015] The utility model discloses dibutyl phthalate continuous production device, through the cooperation of preheating kettle coil, condenser coil, phthalic anhydride activated carbon adsorption tank and n-butanol molecular adsorption tower, the waste heat produced in the working process of condenser is used to preheat kettle, and the raw material is preheated, and the production efficiency and energy utilization rate are greatly improved, and moreover, through phthalic anhydride activated carbon adsorption tank and n-butanol molecular adsorption tower, the impurities produced in the conveying process of raw material are removed, and the product quality is improved, through the cooperation of recovery tank, distillation tower and temporary storage tank, the wastewater produced in neutralization tank and water washing tank is recovered and handled, and n-butanol is recovered for the production of reaction kettle, reduces the wastewater treatment capacity, and improves the raw material utilization rate. BRIEF DESCRIPTION OF DRAWINGS

[0016] Figure 1 It is the structure schematic diagram of dibutyl phthalate continuous production device of the utility model;

[0017] In the drawing: 1, reaction kettle;2, preheating kettle;3, condenser;4, phase separation tower;5, neutralization tank;6, water washing tank;7, decoloring kettle;8, filter;9, rectifying tower;10, recovery tank;11, distillation tower;12, temporary storage tank;13, phthalic anhydride activated carbon adsorption tank;14, n-butanol molecular adsorption tower;15, preheating kettle coil;16, condenser coil;17, connecting pipeline;18, phase separation tower return pipeline;19, water washing tank wastewater collection pipeline;20, neutralization tank wastewater collection pipeline;21, reaction kettle discharge pipeline. DETAILED DESCRIPTION

[0018] In order to make the utility model purpose, technical scheme more clearly, in the following, with the attached drawing, to the utility model further detailed description.

[0019] Example 1

[0020] As Figure 1The dibutyl phthalate continuous production device is shown, including a reaction kettle 1, a n-butanol molecular adsorption tower 14, the n-butanol molecular adsorption tower 14 is connected with the reaction kettle 1 through a preheating kettle 2, the reaction kettle 1 is connected with a water washing tank 6 through a neutralization tank 5, the water washing tank 6 is connected with a rectifying tower 9 through a decoloring kettle 7, the reaction kettle 1 is connected with a phase separation tower 4 through a condenser 3, and the neutralization tank 5 is connected with the reaction kettle 1 through a distillation tower 11. The reaction kettle 1 and the preheating kettle 2 are both provided with stirring devices, so that the pipelines are all provided with heat preservation layers. The reaction kettle 1 is provided with a stirring paddle in the inside, and the reaction kettle 1 is connected with an o-phthalic anhydride activated carbon adsorption tank 13. The preheating kettle 2 is provided with a preheating kettle coil pipe 15 in the inside, the condenser 3 is provided with a condenser coil pipe 16 in the inside, and the condenser coil pipe 16 is connected with the preheating kettle coil pipe 15 through a connecting pipeline 17. The phase separation tower 4 is connected with the reaction kettle 1 through a phase separation tower return pipeline 18, and the phase separation tower 4 is provided with an observation port. A recovery tank 10 is arranged between the neutralization tank 5 and the distillation tower 11, the neutralization tank 5 and the recovery tank 10 are connected with a neutralization tank waste water collecting pipeline 20, the water washing tank 6 is connected with the recovery tank 10 through a water washing tank waste water collecting pipeline 19. The distillation tower 11 is connected with the phase separation tower return pipeline 18 through a temporary storage tank 12, a filter 8 is arranged between the decoloring kettle 7 and the rectifying tower 9, and a reaction kettle discharge pipeline 21 is arranged between the reaction kettle 1 and the neutralization tank 5.

[0021] The dibutyl phthalate continuous production device works, and the following steps are included:

[0022] (1) with phthalic anhydride and n-butanol as the main raw materials, under the action of acid catalyst such as sulfuric acid at 145 DEG C, esterification reaction is carried out, first phthalic anhydride and n-butanol are added to reaction 1 according to the molar ratio: 1:2.5, (2) reaction kettle 1 is provided with stirring device and heating device, water is generated during esterification reaction, in order to make the reaction proceed in the positive direction, the generated water needs to be removed constantly, the way of azeotropic distillation is adopted, n-butanol and water form azeotrope, water is taken out of the reaction system, (3) after azeotrope is condensed, 3 cooled, enters the phase separation tower 4, water phase and organic phase are separated, the organic phase refluxes to the reaction kettle 1 to continue to participate in the reaction, the crude product after reaction contains acidic catalyst, needs to be treated in neutralization tank 5, the neutralizing agent is sodium carbonate solution, (4) the product after neutralization is washed by water in water washing tank 6, to remove residual salts and unreacted raw materials and other impurities, the product after neutralization and washing may contain some pigment and a small amount of solid impurities, needs to be treated by adding activated carbon and other decoloring agents in decoloring kettle 7, after stirring for a certain time in decoloring kettle 7, activated carbon and other solid impurities are removed through filter 8, the relatively pure dibutyl phthalate product is obtained, (5) then through rectifying column 9, according to the different boiling points of dibutyl phthalate and other impurities, further separation and purification are carried out, the high purity product is obtained, (6) recovery tank 10, distillation column 11 and temporary storage tank 12 are used for recycling the waste water generated in neutralization tank 5 and water washing tank 6, the recovered n-butanol enters reaction kettle 1 through pipeline, the waste heat generated in condenser 3 is used for preheating the raw materials in preheating kettle 2.

Claims

1. A continuous production apparatus for dibutyl phthalate, characterized in that, The reaction kettle (1) is connected with the n-butanol molecular adsorption tower (14) through the preheating kettle (2), the reaction kettle (1) is connected with the water washing tank (6) through the neutralization tank (5), the water washing tank (6) is connected with the rectifying tower (9) through the decoloring kettle (7), the reaction kettle (1) is connected with the phase separation tower (4) through the condenser (3), and the neutralization tank (5) is connected with the reaction kettle (1) through the distillation tower (11).

2. The dibutyl phthalate continuous production apparatus according to claim 1, characterized by The inside of the reaction kettle (1) is provided with a stirring paddle, and the reaction kettle (1) is connected with the phthalic anhydride activated carbon adsorption tank (13).

3. The dibutyl phthalate continuous production apparatus according to claim 1, characterized by The inside of the preheating kettle (2) is provided with a preheating kettle coil pipe (15), the inside of the condenser (3) is provided with a condenser coil pipe (16), and the condenser coil pipe (16) is connected with the preheating kettle coil pipe (15) through a connecting pipeline (17).

4. The dibutyl phthalate continuous production apparatus according to claim 1, characterized by The phase separation tower (4) is connected with the reaction kettle (1) through a phase separation tower return pipeline (18), and the phase separation tower (4) is provided with an observation port.

5. The dibutyl phthalate continuous production apparatus according to claim 1, characterized by The neutralization tank (5) and the distillation tower (11) are provided with a recovery tank (10), the neutralization tank (5) and the recovery tank (10) are connected with a neutralization tank wastewater collection pipeline (20), and the water washing tank (6) is connected with the recovery tank (10) through a water washing tank wastewater collection pipeline (19).

6. The dibutyl phthalate continuous production apparatus according to claim 4, characterized by The distillation tower (11) is connected with the phase separation tower return pipeline (18) through a temporary storage tank (12), the decoloring kettle (7) and the rectifying tower (9) are provided with a filter (8), and the reaction kettle (1) and the neutralization tank (5) are provided with a reaction kettle discharge pipeline (21).

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