A continuous clean production device for phenylacetic acid

Abstract

The utility model relates to a kind of phenylacetic acid continuous clean production device, including reaction module, separation module and circulation module;Reaction module includes primary reactor and secondary reactor mutually in series, the top of primary reactor is provided with feed pipe, the surface of primary reactor and secondary reactor is all provided with escape pipe;Separation module includes oil-water separation tower and molecular sieve adsorption tower, oil-water separation tower and the bottom of secondary reactor are connected by pipeline, oil-water separation tower is used for the separation of organic oil phase and salt-containing wastewater, molecular sieve adsorption tower is used for adsorbing residual phenylacetic acid in wastewater;The utility model can recover and adsorb byproduct by molecular sieve adsorption tower, which can recover resources, thereby increasing the recovery structure of byproduct, thereby achieving the treatment and resource utilization of byproduct simultaneously in the production process, which not only can reduce pollutant emission, but also can improve the extraction recovery rate of phenylacetic acid, improve practicality.

Description

Technical Field

[0001] This utility model relates to the field of phenylacetic acid production technology, specifically to a continuous and clean production device for phenylacetic acid. Background Technology

[0002] Phenylacetic acid is an important chemical raw material that plays a vital role in many fields. In the pharmaceutical industry, it is not only a key raw material for penicillin fermentation, but also an important component in the preparation of sedatives, antiepileptic drugs, antidepressants, cardiovascular drugs, and antirheumatic drugs. Meanwhile, in the industrial field, phenylacetic acid also shines brightly, and is widely used in the manufacture of plastic curing agents, fluorescent whitening agents, and color developers.

[0003] Currently, the acidification reaction of phenylacetic acid generates a large amount of acidified wastewater with a high COD value, resulting in high treatment costs. In addition, due to the difference in the solubility of phenylacetic acid in water, a certain amount of phenylacetic acid is carried into the water at each acidification step, affecting the extraction rate. Based on this, a continuous clean production device for phenylacetic acid is proposed to solve the above problems. Utility Model Content

[0004] To address the shortcomings of existing technologies, this invention provides a continuous clean production device for phenylacetic acid, which integrates reaction, separation, and recovery to achieve near-zero emissions of pollutants and resource recycling. It solves the problems of large amounts of acidified wastewater generated during the acidification reaction of phenylacetic acid, which has a high COD value and results in high treatment costs. In addition, due to the difference in the solubility of phenylacetic acid in water, a certain amount of phenylacetic acid is introduced into the water at each acidification step, affecting the extraction rate.

[0005] To achieve the above objectives, this utility model provides the following technical solution: a continuous clean production device for phenylacetic acid, comprising a reaction module, a separation module, and a circulation module;

[0006] The reaction module includes a primary reactor and a secondary reactor connected in series. The primary reactor is equipped with a feed pipe at the top, and both the primary and secondary reactors are equipped with vent pipes on their surfaces.

[0007] The separation module includes an oil-water separation tower and a molecular sieve adsorption tower connected in series. The bottom of the oil-water separation tower and the secondary reactor are connected by a pipeline. The oil-water separation tower is used to separate the organic oil phase and the saline wastewater, and the molecular sieve adsorption tower is used to adsorb residual phenylacetic acid in the wastewater.

[0008] The circulation module includes a temporary storage tank, which is connected to the bottom of the molecular sieve adsorption tower via a pipeline, and the temporary storage tank is connected to the top of the primary reactor via a circulation pipe, on which a diaphragm metering pump is installed.

[0009] Furthermore, the primary reactor is made of Hastelloy C276, and an acid feed pipe is installed on the side of the upper end face of the primary reactor. An alkaline feed pipe is installed at the upper end of the secondary reactor. The reactors need to be adapted to conventional stirring structures. The primary reactor efficiently completes the acidification reaction under acidic conditions of pH 2 to 3, while the secondary reactor adjusts the pH to a neutral range of 6 to 7 by precisely adding alkali, which promotes the full precipitation of unreacted phenylacetate, creating favorable conditions for subsequent separation.

[0010] Furthermore, the lower end of the primary reactor and the top of the secondary reactor are connected by a series pipe, which is equipped with a diaphragm transfer pump. Benzyl chloride undergoes an acidification reaction in the primary reactor, and the acidified material is then sent to the secondary reactor through the series pipe for precipitation.

[0011] Furthermore, the inner walls of both the primary and secondary reactors are coated with a polytetrafluoroethylene-carbon nanotube composite coating, and an array of ultrasonic transducers are fixedly installed on the outer wall of the secondary reactor. Multiple ultrasonic transducers generate ultrasonic shock waves, which can break the bonding force between the crystals and the coating. The coating is made of 20% highly conductive carbon nanotubes and 80% hydrophobic polytetrafluoroethylene (uniform coating thickness of 150μm). This coating is prepared by chemical vapor deposition to form a superhydrophobic surface structure, thereby reducing the adhesion of crystals and simultaneously adapting to the ultrasonic field of the ultrasonic shock waves to achieve self-cleaning of the reactor inner wall, reduce maintenance cycles, and improve practicality.

[0012] Furthermore, the top of the oil-water separation tower is connected to a finished product tank via a pipeline. The oil-water separation tower is a centrifugal separation device, and the oil phase separated in the oil-water separation tower is pumped to the finished product tank via a pipeline.

[0013] Furthermore, the interior of the molecular sieve adsorption tower is filled with molecular sieves, and a backwashing component is provided at the upper end of the interior of the molecular sieve adsorption tower. A heating component is installed on the outer wall of the molecular sieve adsorption tower. The regular channel structure of the molecular sieve (pore size of about 0.55nm) is highly matched with the molecular size of phenylacetic acid.

[0014] The backwashing assembly includes an annular flushing pipe with flushing nozzles arranged in an annular array on the lower end face of the annular flushing pipe. The annular flushing pipe is connected to an external water supply pump through a water supply pipe.

[0015] Furthermore, the heating assembly consists of a jacketed shell fixedly connected to the outer wall of the molecular sieve adsorption tower. The jacketed shell and the molecular sieve adsorption tower form a heating chamber, in which a spiral heating tube is installed. The height of the heating chamber is adapted to the filling height of the molecular sieve. After saturation adsorption, the high-concentration phenylacetic acid solution (approximately 15-20%) is regenerated through thermal desorption and returned to the synthesis reactor as a raw material for recycling, thereby reducing the generation of pollutants.

[0016] Furthermore, the storage tank is equipped with a filter screen and an activated carbon adsorption screen inside, and a stirring motor is installed on the top of the storage tank. A stirring structure is installed inside the storage tank, and the output end of the stirring motor is connected to the stirring structure. The solution recovered by thermal desorption needs to be sent into the storage tank for buffering and temporary storage. The temporary storage temperature is maintained at 40-50℃ to prevent phenylacetic acid from crystallizing out.

[0017] Compared with the prior art, the technical solution of this application has the following beneficial effects:

[0018] This continuous clean production unit for phenylacetic acid utilizes a molecular sieve adsorption tower to recover and adsorb byproducts, thereby increasing the recovery capacity of production byproducts. This allows for the simultaneous processing and resource utilization of byproducts during production, reducing pollutant emissions and improving the extraction and recovery rate of phenylacetic acid, thus enhancing its practicality. Attached Figure Description

[0019] Figure 1 The diagram shown is a schematic representation of the overall structure of this utility model.

[0020] Figure 2 The diagram shown is a top view of the secondary reactor of this utility model.

[0021] Figure 3 The diagram shown is a schematic diagram of the annular flushing pipe structure of this utility model;

[0022] Figure 4 The diagram shown is a schematic of the sandwich shell structure of this utility model;

[0023] Figure 5 The diagram shown is a structural schematic of another embodiment of this utility model.

[0024] Explanation of reference numerals in the attached diagram: 11. Primary reactor; 12. Secondary reactor; 121. Ultrasonic transducer end; 13. Evaporation pipe; 14. Oil-water separation tower; 15. Molecular sieve adsorption tower; 151. Annular flushing pipe; 152. Jacketed shell; 153. Spiral heating pipe; 16. Temporary storage tank; 17. Circulation pipe; 18. Diaphragm metering pump; 2. Finished product tank. Detailed Implementation

[0025] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0026] Please see Figures 1-5The continuous clean production apparatus for phenylacetic acid in this embodiment includes a reaction module, a separation module and a circulation module;

[0027] The reaction module includes a primary reactor 11 and a secondary reactor 12 connected in series. The top of the primary reactor 11 is provided with a feed pipe, and the surfaces of the primary reactor 11 and the secondary reactor 12 are provided with vent pipes 13.

[0028] The separation module includes an oil-water separation tower 14 and a molecular sieve adsorption tower 15 connected in series. The bottom of the oil-water separation tower 14 and the secondary reactor 12 are connected by a pipeline. The oil-water separation tower 14 is used to separate the organic oil phase and the saline wastewater, and the molecular sieve adsorption tower 15 is used to adsorb residual phenylacetic acid in the wastewater.

[0029] The circulation module includes a temporary storage tank 16, which is connected to the bottom of the molecular sieve adsorption tower 15 via a pipeline, and the temporary storage tank 16 is connected to the top of the primary reactor 11 via a circulation pipe 17, on which a diaphragm metering pump 18 is installed.

[0030] In this embodiment, the primary reactor 11 is made of Hastelloy C276, which has excellent corrosion resistance. An acid feed pipe is provided on the side of the upper end of the primary reactor 11, and an alkaline feed pipe is provided on the upper end of the secondary reactor 12. The lower end of the primary reactor 11 and the top of the secondary reactor 12 are connected by a series pipe, which is equipped with a diaphragm pump. Benzyl chloride undergoes an acidification reaction in the primary reactor 11, and the acidified material is sent to the secondary reactor 12 through the series pipe for precipitation. The raw material solution is first fed into the primary reactor 11 through the feed pipe. The series connection of the primary reactor 11 and the secondary reactor 12 enables continuous production and shortens the production cycle.

[0031] It should be noted that the vent pipe 13 is used to collect the waste gas generated during the reaction process and to achieve centralized treatment of the waste gas, while the wastewater after adsorption by the molecular sieve adsorption tower 15 also needs to enter the wastewater treatment equipment for secondary treatment.

[0032] Please see Figure 1 and Figure 2 In this embodiment, the inner walls of both the primary reactor 11 and the secondary reactor 12 are coated with a polytetrafluoroethylene-carbon nanotube composite coating, and an array of ultrasonic transducer ends 121 are fixedly installed on the outer wall of the secondary reactor 12. Multiple ultrasonic transducer ends 121 form ultrasonic shock waves, which can destroy the bonding force between the crystal and the coating.

[0033] It should be noted that the ultrasonic transducer end 121 is an existing structure, which generally consists of a transducer and a frequency control module. The transducer is a PZT-8 type lead zirconate titanate piezoelectric ceramic, and the electrode structure is a double-sided silver-plated electrode (2μm thick), with a polyimide protective film covering the surface of the silver layer.

[0034] Please see Figures 1-4 In this embodiment, the top of the oil-water separation tower 14 is connected to the finished product tank 2 via a pipeline. The oil-water separation tower 14 is a centrifugal separation device, and the oil phase separated in the oil-water separation tower 14 is pumped to the finished product tank 2 via a pipeline.

[0035] In this embodiment, the molecular sieve adsorption tower 15 is filled with molecular sieves, and a backwashing assembly is provided at the upper end of the molecular sieve adsorption tower 15. A heating assembly is installed on the outer wall of the molecular sieve adsorption tower 15. The backwashing assembly includes an annular flushing pipe 151, and a ring array of flushing nozzles is provided on the lower end face of the annular flushing pipe 151. The annular flushing pipe 151 is connected to an external water supply pump through a water supply pipe. The heating assembly consists of a sandwich shell 152 fixedly connected to the outer wall of the molecular sieve adsorption tower 15. The sandwich shell 152 and the molecular sieve adsorption tower 15 form a heating chamber. A spiral heating pipe 153 is provided in the heating chamber. The height of the heating chamber is adapted to the molecular sieve filling height (the spiral heating pipe 153 is equipped with a PID temperature control module, which adjusts the temperature in stages according to the needs of the desorption stage. The temperature is usually set to 150-200℃).

[0036] It should be noted that the molecular sieve adsorption tower 15 can adsorb phenylacetic acid in the aqueous phase, and after adsorption saturation, the adsorbed phenylacetic acid can be desorbed by backwashing and heating desorption, which increases resource utilization, reduces COD value, and improves practicality.

[0037] Please see Figure 1 In this embodiment, the temporary storage tank 16 is equipped with a filter screen and an activated carbon adsorption screen inside, and a stirring motor is installed on the top of the temporary storage tank 16. A stirring structure is provided on the inner side of the temporary storage tank 16, and the output end of the stirring motor is connected to the stirring structure.

[0038] It should be noted that the temporary storage tank 16 is generally equipped with a concentration detection structure and a pH adjustment structure. The concentration detection structure uses an online refractometer or HPLC analysis to ensure that the solution concentration meets the reuse standard. The pH adjustment structure works in conjunction with the stirring structure to add acid-base adjusters to control the pH in the range of 6.5-7.5.

[0039] In this embodiment, the temporary storage tank 16 has a built-in double-layer filter, which can remove suspended solids and trace organic matter from the recycled water, preventing impurities from entering the reactor and affecting the purity of the product. At the same time, the recycled material is transported back to the primary reactor 11 through a diaphragm metering pump (flow accuracy ±1%), and the ratio of recycled material to raw material is 1:4.

[0040] Please see Figure 5In another embodiment based on the separation module, a distillation tank is added between the temporary storage tank 16 and the molecular sieve adsorption tower 15, so that the precipitated solution is purified by distillation. When there are many impurities in the precipitate, it is first purified by distillation and then temporarily stored in a buffer.

[0041] The working principle of the above embodiments is as follows:

[0042] The raw material solution (containing benzyl chloride) enters the primary reactor 11 through the feed pipe, while acid is added through the acid feed pipe to carry out the acidification reaction. The acidified material enters the secondary reactor 12 through the series pipe (with diaphragm pump), and alkaline solution is added through the alkaline feed pipe to precipitate phenylacetic acid. The ultrasonic transducer end on the outer wall of the secondary reactor 12 generates shock waves to break the bonding force between the crystal and the coating, preventing the material from adhering to the inner wall. The material from the secondary reactor 12 (containing phenylacetic acid crystals, organic oil phase, and saline wastewater) enters the oil-water separation tower 14. The separated organic oil phase (containing phenylacetic acid) is pumped into the finished product tank to obtain the crude product (the product is crystallized). The separated saline wastewater enters the molecular sieve adsorption tower 15 to adsorb the residual phenylacetic acid in the wastewater through the molecular sieve. After adsorption saturation, the backwashing and heating components are activated to desorb the adsorbed phenylacetic acid, achieving resource recovery and reducing the COD value of the wastewater. The desorbed liquid is sent to the temporary storage tank 16 for storage, and then undergoes double-layer filtration to remove suspended solids and trace organic matter. The pH is controlled at 6.5-7.5 by a pH adjustment structure, and the concentration is detected by an online refractometer / HPLC to ensure the reuse standard. The treated reclaimed water is pumped back to the primary reactor 11 by the diaphragm metering pump 18 at a ratio of 1:4 between the recovered material and the raw material, realizing water resource recycling and reducing emissions.

[0043] It should be noted that the control method of this utility model is controlled by a controller. The control circuit of the controller can be implemented by those skilled in the art through simple programming. The power supply is also common knowledge in the field. Furthermore, this utility model is mainly used to protect mechanical devices, so the control method and circuit connection will not be explained in detail here.

[0044] It should be noted that, in this document, relational terms such as "first" and "second" are used only to distinguish one entity or operation from another, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Furthermore, the terms "comprising," "including," or any other variations thereof are intended to cover non-exclusive inclusion, such that a process, method, article, or apparatus that comprises a list of elements includes not only those elements but also other elements not expressly listed, or elements inherent to such a process, method, article, or apparatus. Without further limitations, an element defined by the phrase "comprising one..." does not exclude the presence of other identical elements in the process, method, article, or apparatus that includes said element.

[0045] Although embodiments of the present invention have been shown and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made to these embodiments without departing from the principles and spirit of the present invention, the scope of which is defined by the appended claims and their equivalents.

Claims

1. A continuous clean production apparatus for phenylacetic acid, characterized in that: It includes a reaction module, a separation module, and a circulation module; The reaction module includes a primary reactor (11) and a secondary reactor (12) connected in series. The top of the primary reactor (11) is provided with a feed pipe, and the surfaces of the primary reactor (11) and the secondary reactor (12) are provided with vent pipes (13). The separation module includes an oil-water separation tower (14) and a molecular sieve adsorption tower (15) connected in series. The bottom of the oil-water separation tower (14) and the secondary reactor (12) are connected by a pipeline. The oil-water separation tower (14) is used to separate the organic oil phase and the saline wastewater, and the molecular sieve adsorption tower (15) is used to adsorb residual phenylacetic acid in the wastewater. The circulation module includes a temporary storage tank (16), the bottom of which is connected to the molecular sieve adsorption tower (15) by a pipeline, and the top of which is connected to the primary reactor (11) by a circulation pipe (17), on which a diaphragm metering pump (18) is installed.

2. The continuous clean production apparatus for phenylacetic acid according to claim 1, characterized in that: The primary reactor (11) is made of Hastelloy C276 material, and an acid feed pipe is provided on the primary reactor (11). An alkaline feed pipe is provided at the upper end of the secondary reactor (12).

3. The continuous clean production apparatus for phenylacetic acid according to claim 1, characterized in that: The lower end of the primary reactor (11) and the top of the secondary reactor (12) are connected by a series pipe. A diaphragm delivery pump is installed on the series pipe. Benzyl chloride undergoes an acidification reaction in the primary reactor (11), and the acidified material is sent to the secondary reactor (12) through the series pipe for precipitation.

4. The continuous clean production apparatus for phenylacetic acid according to claim 1, characterized in that: The inner walls of both the primary reactor (11) and the secondary reactor (12) are coated with a polytetrafluoroethylene-carbon nanotube composite coating. An array of ultrasonic transducer ends (121) are fixedly installed on the outer wall of the secondary reactor (12). Multiple ultrasonic transducer ends (121) form ultrasonic shock waves, which can destroy the bonding force between the crystal and the coating.

5. The continuous clean production apparatus for phenylacetic acid according to claim 1, characterized in that: The top of the oil-water separation tower (14) is connected to the finished product tank (2) via a pipeline. The oil-water separation tower (14) is a centrifugal separation device. The oil phase separated in the oil-water separation tower (14) is pumped to the finished product tank (2) via a pipeline.

6. The continuous clean production apparatus for phenylacetic acid according to claim 1, characterized in that: The interior of the molecular sieve adsorption tower (15) is filled with molecular sieves, and a backwashing component is provided at the upper end of the interior of the molecular sieve adsorption tower (15), and a heating component is installed on the outer wall of the molecular sieve adsorption tower (15). The backwash assembly includes an annular flushing pipe (151), the lower end face of which is provided with flushing nozzles arranged in an annular array, and the annular flushing pipe (151) is connected to an external water supply pump through a water supply pipe.

7. The continuous clean production apparatus for phenylacetic acid according to claim 1, characterized in that: The heating assembly consists of a sandwich shell (152) fixedly connected to the outer wall of the molecular sieve adsorption tower (15). The sandwich shell (152) and the molecular sieve adsorption tower (15) form a heating chamber. A spiral heating tube (153) is installed in the heating chamber. The height of the heating chamber is adapted to the filling height of the molecular sieve.

8. The continuous clean production apparatus for phenylacetic acid according to claim 1, characterized in that: The storage tank (16) is equipped with a filter screen and an activated carbon adsorption screen inside, and a stirring motor is installed on the top of the storage tank (16). A stirring structure is provided on the inner side of the storage tank (16), and the output end of the stirring motor is connected to the stirring structure.

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