Continuous production device and method for esterification of 2-ethylhexyl acrylate

Abstract

The invention relates to a continuous production device and method for esterification of 2-ethylhexyl acrylate. The continuous production device is characterized by comprising a tubular continuous esterification reactor, an intermediate tank, a catalyst recovery tower, a washing tower, a dealcoholization tower, a rectifying tower, a dehydrating tower and a finished product storage tank, compared with an original isooctyl acrylate production process, an intermittent production process is changed into a continuous production process, so that the energy consumption and the use of a tubular reactor can be effectively reduced, the utilization rate of equipment is improved, the productivity is improved, and the consistency of the esterification conversion rate of raw materials is ensured; compared with previous kettle type intermittent feeding, continuous feeding has the advantages that the production stability and safety are improved, the esterification mode is changed, and the color number increase of products caused by polymerization and oxidation of the products in a production system is effectively reduced.

Description

Technical Field

[0001] The invention relates to the technical field of isooctyl acrylate production, and in particular to a device and method for continuously producing isooctyl acrylate by esterification. Background Art

[0002] Isooctyl acrylate is an excellent organic solvent and a relatively soft monomer. It is widely used in various polymer systems as a plasticizing comonomer to adjust the softness of polymers. It can be used to make emulsion polymers, which have room-temperature viscosity, adhesion and cohesion after film formation. It is used to make pressure-sensitive adhesives, sealing adhesives, elastic coatings, high-end industrial automotive paints, etc. Its excellent performance is increasingly welcomed by the market and has a good market prospect.

[0003] The existing methods for producing isooctyl acrylate mostly adopt the method of esterification of acrylic acid and octanol with p-toluenesulfonic acid as catalyst, with excess acrylic acid and p-toluenesulfonic acid as catalyst, and the esterification reaction is carried out in an esterification reactor, and the reaction product is separated by catalyst and ester water to obtain crude ester, and then the crude ester is de-lightened and refined, and the isooctyl acrylate product is obtained after purification. However, the quality of the finished product obtained by the above method has the following shortcomings: 1. The production time is long, and the system reaction is prone to polymer; 2. Due to the long production time, the material polymerization leads to high chromaticity; 3. This method is an intermittent reaction, the esterification efficiency is low, and the ester content is low.

[0004] Therefore, it is necessary to choose a new esterification method, which can not only reduce the formation of polymers in production, but also improve the esterification efficiency and ester content, thereby improving the product quality and production efficiency of isooctyl acrylate.

[0005] The current production process is as follows: Figure 1 shown.

[0006] Description of the main production process: as attached Figure 1 As shown, first, acrylic acid and catalyst are transported into the primary esterification kettle in proportion through a delivery pump, isooctyl alcohol and polymerization inhibitor are transported to a water washing tower through a delivery pump, and then enter the primary esterification kettle to carry out a primary esterification reaction with acrylic acid and catalyst. After a certain degree of reaction, the materials enter the secondary esterification kettle to continue the esterification reaction. The water phase produced by the primary and secondary esterification kettles is sent to a dehydration tower for dehydration treatment, and the isooctyl alcohol and catalyst in the dehydration tower are recycled to the esterification kettle to participate in the esterification reaction. After cooling, the esterification reaction liquid enters a catalyst recovery tower, and the catalyst therein is concentrated and recovered after water extraction, and the recovered catalyst is returned to the dehydration tower for reuse. The residual liquid of the catalyst recovery tower enters a washing tower, and is washed with desalted water to remove the residual acrylic acid and catalyst. The top material is then removed by a dealcoholization tower to remove the remaining octanol, and the octanol recovered from the top of the dealcoholization tower is circulated to the dehydration tower for reuse, and the bottom liquid is purified by an ester rectification tower to obtain an acrylic acid ester isooctyl ester product with a purity greater than 99.5%.

[0007] The main equipment required for the production process of isooctyl acrylate are: 1. primary esterification kettle, 2. secondary esterification kettle, 3. dehydration tower, 4. catalyst recovery tower, 5. washing tower, 6. dealcoholization tower, 7. distillation tower, 8. isooctyl acrylate finished product tank.

[0008] Main equipment connection methods in the production process of 2-ethylhexyl acrylate:

[0009] The acrylic acid and catalyst feed pumps are connected to the primary esterification kettle via pipeline A;

[0010] The primary ester outlet is connected to the secondary esterification kettle via pipeline B;

[0011] The water phase outlet of the primary esterification kettle is connected to the dehydration tower through pipeline C;

[0012] The water phase outlet of the secondary esterification kettle is connected to the dehydration tower through pipeline D;

[0013] The raw materials isooctyl alcohol, polymerization inhibitor, and toluene are connected to the dehydration tower via pipeline E;

[0014] Part of the isooctyl alcohol and part of the catalyst recovered from the dehydration tower are connected to the primary esterification kettle through pipeline F;

[0015] The isooctyl alcohol and water that are not completely condensed at the top of the dehydration tower are connected to the catalyst recovery tower through pipeline G;

[0016] The crude ester in the secondary esterification reactor is connected to the catalyst recovery tower via pipeline H;

[0017] The catalyst recovered by the catalyst recovery tower is connected to the dehydration tower via pipeline I;

[0018] The catalyst recovery tower carrying the crude octanol ester material is connected to the washing tower through pipeline J;

[0019] The oil phase material of the washing tower is connected to the dealcoholization tower through pipeline K;

[0020] The octanol removed from the dealcoholization tower is connected to the dehydration tower via pipeline L;

[0021] The crude isooctyl acrylate at the bottom of the dealcoholization tower is connected to the distillation tower via a pipeline M;

[0022] The isooctyl acrylate product at the bottom of the distillation tower is connected to the product tank through N.

[0023] In the above existing processes and equipment: in the production process of isooctyl acrylate, the original esterification production process requires the esterification reaction to be heated in stages through the primary and secondary esterification kettles of the raw materials. The conversion rate of the esterification reaction is unstable, and the residence time in the kettle leads to an increase in the polymerization reaction of the esterified product. Summary of the invention

[0024] The technical problem to be solved by the present invention is to provide a continuous esterification production device and method for isooctyl acrylate, which adopts a method of replacing the original esterification production by changing the esterification reaction equipment. The method changes the esterification process, reduces the polymer generated during the esterification reaction, improves the esterification efficiency and ester content, and thus improves the product quality and production efficiency of isooctyl acrylate.

[0025] In order to solve the above technical problems, the technical solution of the present invention is: a continuous production device for esterification of isooctyl acrylate, the innovation of which is: comprising a tubular continuous esterification reactor, an intermediate tank, a catalyst recovery tower, a washing tower, a dealcoholization tower, a distillation tower, a dehydration tower and a finished product storage tank;

[0026] The input end of the tubular continuous esterification reactor is connected to the outlets of acrylic acid, isooctyl alcohol and catalyst feed pumps through pipeline A; the output end of the tubular continuous esterification reactor is connected to the intermediate tank through pipeline B;

[0027] The oil phase in the intermediate tank is connected to the catalyst recovery tower through pipeline C; the water phase in the intermediate tank is connected to the dehydration tower through pipeline D;

[0028] The side of the dehydration tower is connected to the outlet of the polymerization inhibitor and toluene feed pump through pipeline E; the top of the dehydration tower is connected to the side of the catalyst recovery tower through pipeline F, so that the isooctyl alcohol and water that are not completely condensed at the top of the dehydration tower are transported to the catalyst recovery tower; the bottom of the dehydration tower is connected to the input end of the tubular continuous esterification reactor through pipeline M, so that part of the recovered isooctyl alcohol and part of the catalyst are transported to the tubular continuous esterification reactor;

[0029] The top of the catalyst recovery tower is connected to the side of the washing tower through a pipeline G to transport the crude octanol ester material to the dehydration tower; the bottom of the catalyst recovery tower is connected to the dehydration tower through a pipeline H;

[0030] The top of the washing tower is connected to the side of the dealcoholization tower through a pipeline I, so as to transport the oil phase material in the washing tower to the dealcoholization tower;

[0031] The top of the dealcoholization tower is connected to the side of the dehydration tower through a pipeline J to transport the octanol in the dealcoholization tower to the dehydration tower; the bottom of the dealcoholization tower is connected to the side of the distillation tower through a pipeline K;

[0032] The bottom end of the distillation tower is connected to the finished product storage tank through a pipeline L.

[0033] A method for continuous production of isooctyl acrylate by esterification, the innovation of which is as follows:

[0034] Acrylic acid and isooctyl alcohol are pumped into a tubular reactor in a ratio of 0.54:1 through a metering pump for reaction until the temperature of the tubular reactor reaches 95-105°C and the pressure is less than 30kPa;

[0035] The feeding amount of acrylic acid and isooctyl alcohol is controlled by adjusting the frequency conversion of the feeding pump, and the outlet temperature of the material at the tubular reactor container is ensured to be stable at 95-105°C by adjusting the steam regulating valve of the tubular reactor jacket;

[0036] After continuous feeding, pay attention to the changes in temperature, pressure and liquid level of crude isooctyl acrylate intermediate tank in the tubular reactor to ensure stable and continuous normal production;

[0037] Samples are taken regularly from the outlet of the tubular continuous esterification reactor and the intermediate tank, and the content of isooctyl acrylate reaction materials can be determined through analysis.

[0038] The advantages of the present invention are:

[0039] 1) In the present invention, the raw materials are mixed and then passed through a tubular continuous esterification reactor, and the tubular continuous esterification reactor is filled with a catalyst of p-toluenesulfonic acid, and the heating reaction can be continuously produced, thereby reducing the esterification conversion rate and the problem of unstable product quality in the esterification production process, and greatly reducing the production energy consumption.

[0040] 2) Compared with the original isooctyl acrylate production process, the present invention changes the intermittent type into a continuous type, and the use of a tubular reactor improves the utilization rate of the equipment and the production capacity, and ensures the consistency of the esterification conversion rate of the raw materials; compared with the original isooctyl acrylate production process, the continuous feeding improves the stability and safety of production compared with the previous kettle-type intermittent feeding, changes the esterification mode, and effectively reduces the increase in product color caused by product polymerization oxidation in the production system. BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The present invention will be further described in detail below in conjunction with the accompanying drawings and specific embodiments.

[0042] Figure 1 This is the existing production process flow chart of isooctyl acrylate.

[0043] Figure 2 This is a diagram of a continuous production device for esterification of isooctyl acrylate according to the present invention. DETAILED DESCRIPTION

[0044] In order to make the purpose, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the embodiments of the present invention, not all of the embodiments. Generally, the components of the embodiments of the present invention described and shown in the drawings here can be arranged and designed in various different configurations.

[0045] Therefore, the following detailed description of the embodiments of the present invention provided in the accompanying drawings is not intended to limit the scope of the invention claimed for protection, but merely represents selected embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0046] like Figure 1 The continuous production device for esterification of isooctyl acrylate shown includes a tubular continuous esterification reactor 01, an intermediate tank 02, a dehydration tower 03, a catalyst recovery tower 04, a washing tower 05, a dealcoholization tower 06, a distillation tower 07 and a finished product storage tank 08.

[0047] The input end of the tubular continuous esterification reactor 01 is connected to the outlets of acrylic acid, isooctyl alcohol and catalyst feed pumps through pipeline A; the output end of the tubular continuous esterification reactor 01 is connected to the intermediate tank 02 through pipeline B.

[0048] The oil phase in the intermediate tank 02 is connected to the catalyst recovery tower 04 through pipeline C; the water phase in the intermediate tank 02 is connected to the dehydration tower 03 through pipeline D.

[0049] The side of the dehydration tower 03 is connected to the outlet of the inhibitor and toluene feed pump through pipeline E; the top of the dehydration tower 03 is connected to the side of the catalyst recovery tower 04 through pipeline F, so that the isooctyl alcohol and water that are not completely condensed at the top of the dehydration tower 03 are transported to the catalyst recovery tower 04; the bottom end of the dehydration tower 03 is connected to the input end of the tubular continuous esterification reactor 01 through pipeline M, so that part of the recovered isooctyl alcohol and part of the catalyst are transported to the tubular continuous esterification reactor 01.

[0050] The top of the catalyst recovery tower 04 is connected to the side of the washing tower 05 through the pipeline G to transport the crude octanol ester material to the dehydration tower 03; the bottom of the catalyst recovery tower 04 is connected to the dehydration tower through the pipeline H.

[0051] The top of the washing tower 05 is connected to the side of the dealcoholization tower 06 through a pipeline I, so that the oil phase material in the washing tower 05 is transported to the dealcoholization tower 06.

[0052] The top of the dealcoholization tower 06 is connected to the side of the dehydration tower 03 through a pipeline J, and the octanol in the dealcoholization tower 06 is transported to the dehydration tower 03; the bottom of the dealcoholization tower 06 is connected to the side of the distillation tower 07 through a pipeline K.

[0053] The bottom end of the distillation tower 07 is connected to the finished product storage tank 08 via a pipeline L.

[0054] A method for continuous production of isooctyl acrylate by esterification, the specific production method is as follows:

[0055] Acrylic acid and isooctyl alcohol are pumped into a tubular reactor in a ratio of 0.54:1 through a metering pump for reaction until the temperature of the tubular reactor reaches 95-105°C and the pressure is less than 30kPa;

[0056] The feeding amount of acrylic acid and isooctyl alcohol is controlled by adjusting the frequency conversion of the feeding pump, and the outlet temperature of the material at the tubular reactor container is ensured to be stable at 95-105°C by adjusting the steam regulating valve of the tubular reactor jacket;

[0057] After continuous feeding, pay attention to the changes in temperature, pressure and liquid level of crude isooctyl acrylate intermediate tank in the tubular reactor to ensure stable and continuous normal production;

[0058] Samples are taken regularly from the outlet of the tubular continuous esterification reactor and the intermediate tank, and the content of isooctyl acrylate reaction materials can be determined through analysis.

[0059] Those skilled in the art should understand that the present invention is not limited to the above-mentioned embodiments. The above-mentioned embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may be subject to various changes and improvements, and these changes and improvements shall all fall within the scope of the present invention claimed for protection.

Claims

1. A continuous production device for esterification of isooctyl acrylate, characterized in that: It includes a tubular continuous esterification reactor, an intermediate tank, a catalyst recovery tower, a washing tower, a dealcoholization tower, a distillation tower, a dehydration tower and a finished product storage tank; The input end of the tubular continuous esterification reactor is connected to the outlets of acrylic acid, isooctyl alcohol and catalyst feed pumps through pipeline A; the output end of the tubular continuous esterification reactor is connected to the intermediate tank through pipeline B; The oil phase in the intermediate tank is connected to the catalyst recovery tower through pipeline C; the water phase in the intermediate tank is connected to the dehydration tower through pipeline D; The side of the dehydration tower is connected to the outlet of the polymerization inhibitor and toluene feed pump through pipeline E; the top of the dehydration tower is connected to the side of the catalyst recovery tower through pipeline F, so that the isooctyl alcohol and water that are not completely condensed at the top of the dehydration tower are transported to the catalyst recovery tower; the bottom of the dehydration tower is connected to the input end of the tubular continuous esterification reactor through pipeline M, so that part of the recovered isooctyl alcohol and part of the catalyst are transported to the tubular continuous esterification reactor; The top of the catalyst recovery tower is connected to the side of the washing tower through a pipeline G to transport the crude octanol ester material to the dehydration tower; the bottom of the catalyst recovery tower is connected to the dehydration tower through a pipeline H; The top of the washing tower is connected to the side of the dealcoholization tower through a pipeline I, so as to transport the oil phase material in the washing tower to the dealcoholization tower; The top of the dealcoholization tower is connected to the side of the dehydration tower through a pipeline J to transport the octanol in the dealcoholization tower to the dehydration tower; the bottom of the dealcoholization tower is connected to the side of the distillation tower through a pipeline K; The bottom end of the distillation tower is connected to the finished product storage tank through a pipeline L.

2. A method for continuous production of isooctyl acrylate by esterification, characterized in that: The specific production method is as follows: Acrylic acid and isooctyl alcohol are pumped into a tubular reactor in a ratio of 0.54:1 through a metering pump for reaction until the temperature of the tubular reactor reaches 95-105°C and the pressure is less than 30kPa; The feeding amount of acrylic acid and isooctyl alcohol is controlled by adjusting the frequency conversion of the feeding pump, and the outlet temperature of the material at the tubular reactor container is ensured to be stable at 95-105°C by adjusting the steam regulating valve of the tubular reactor jacket; After continuous feeding, pay attention to the changes in temperature, pressure and liquid level of crude isooctyl acrylate intermediate tank in the tubular reactor to ensure stable and continuous normal production; Samples are taken regularly from the outlet of the tubular continuous esterification reactor and the intermediate tank, and the content of isooctyl acrylate reaction materials can be determined through analysis.

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