CN222056372U - Device for continuously producing isosorbide - Google Patents

Abstract

The utility model relates to a device for continuously producing isosorbide, which comprises a first-stage reactor, a second-stage reactor, a separator and a vacuum unit, wherein the first-stage reactor, the second-stage reactor, the separator and the vacuum unit are sequentially arranged along the synthesis direction of the isosorbide, and the first-stage reactor is a place for obtaining 1, 4-sorbitan and isosorbide through dehydration of sorbitol through a first-stage reaction; the secondary reactor is a place where the 1, 4-sorbitan is dehydrated through a secondary reaction to generate isosorbide, and the gaseous mixture of the isosorbide and water is distilled out synchronously; the separator is a location where water is separated from the gaseous mixture; the primary reactor, the secondary reactor and the separator are all connected with a vacuum unit; the secondary reactor is a stirred tank reactor or a molecular distiller. The equipment can realize continuous production of the isosorbide, and has high product yield and content, high production efficiency and low energy consumption.

Description

Device for continuously producing isosorbide

Technical Field

The application relates to the technical field of chemical equipment, in particular to a device for continuously producing isosorbide.

Background

Isosorbide is the secondary dehydration product of D-sorbitol, also known as isosorbide; 1:4; 3:6-dianhydro-D-sorbitol. It is a commonly used oral osmotic dehydration diuretic with a mechanism of action similar to intravenous mannitol and sorbitol, and by increasing plasma osmotic pressure, it causes water in tissues (including eye, brain, cerebrospinal fluid, etc.) to enter into blood vessels, thereby alleviating tissue edema, lowering intraocular pressure, intracranial pressure and cerebrospinal fluid volume and pressure. In industry, isosorbide is used as an important raw material and an intermediate of Span and Tween surfactants and is applied to the fields of national defense, electronics, cosmetics industry and the like. In recent years, isosorbide has been added to PET as a polymer additive to raise the glass transition temperature of the polymer, increase the strength of the polymer, and expand the market for the polymer.

The traditional method for preparing the isosorbide is kettle reaction with liquid acid as a catalyst, and the catalyst cannot be recovered and can generate pollution; the byproducts are more, the yield is low, the equipment corrosion is serious, and continuous production can not be realized. The equipment used by the method is mainly a simple method in a laboratory preparation process, kettle type intermittent reaction, simple distillation and crystallization operation are mostly adopted to obtain a crude product of the isosorbide, and then the crude product of the isosorbide is refined to obtain the product of the isosorbide. Intermittent preparation of isosorbide has the problems of low raw material utilization rate, unstable preparation process, unstable product quality, difficult purification and separation of products and the like.

In order to solve the problems, and realize continuous production of isosorbide, the prior researches continuously improve the production of isosorbide. For example, the patent publication No. CN204752581U provides a continuous production apparatus for producing isosorbide from sorbitol, comprising: the device comprises a raw material premixing device, a primary dehydration reactor, a middle dehydration device, a secondary dehydration reactor, a neutralization deacidification reactor, a rectifying tower, an isosorbide condenser, a desalting and impurity device, a connecting pipeline between devices, a control instrument and various accessories; the preparation process is that sorbitol and dehydration catalyst are pre-mixed in a raw material pre-mixing device in proportion, and then enter a first-stage dehydration reactor for reaction, and finally enter a second-stage dehydration reactor for further completion of dehydration reaction after dehydration in an intermediate dehydration device. The device for preparing isosorbide by dehydrating sorbitol can continuously prepare isosorbide, has good product quality, less byproducts, high raw material utilization rate, stable preparation process and high operation elasticity. However, the device is used for neutralizing an acidic catalyst after reaction and redistilling, the yield and content of the prepared product are low, the kettle residue is easy to be seriously carbonized, and after long-term use, the reactor needs to be cleaned, so that the negative influence on equipment is large, and the service life is low. In addition, the device needs a plurality of equipment to be used jointly, and the energy consumption is big, and economic cost is high.

The publication No. CN103980286B also provides a method for continuously producing isosorbide and a device used by the method, wherein the device comprises a reactor, a condenser consisting of a first condenser and a second condenser, a vacuum system and a temperature control system; the reactor is connected with a first condenser, and the first condenser is connected with a second condenser; the reactor, the first condenser and the second condenser are communicated with a vacuum system; the reactor, the first condenser and the second condenser are respectively connected with a temperature control system; the first condenser and the second condenser are respectively connected with the finished product tank and the wastewater tank. However, the device needs to be heated to carry out two-step dehydration reaction, and the removal form of the residue of the kettle is not considered. The device has longer reaction time and higher energy consumption.

In sum, if the device for continuously producing the isosorbide can be provided, the short reaction time, high product yield, low energy consumption and less negative influence on the device can be realized, the continuous preparation of the isosorbide can be realized, and the device has important significance on improving the preparation level of the isosorbide in China and meeting the market demand of future markets for the isosorbide.

Disclosure of utility model

In view of the shortcomings of the prior art, the utility model provides a device for continuously producing isosorbide, which aims to solve the problems that isosorbide production equipment is easy to corrode, high in energy consumption, incapable of continuous production, poor in product quality and the like in the prior art.

In order to achieve the above and related objects, the present utility model adopts the following technical scheme:

A device for continuously producing isosorbide comprises a first-stage reactor, a second-stage reactor, a separator and a vacuum unit which are sequentially arranged along the synthesis direction of isosorbide, wherein the first-stage reactor is a place where sorbitol is dehydrated through a first-stage reaction to obtain 1, 4-sorbitan and isosorbide; the secondary reactor is a place where the 1, 4-sorbitan is dehydrated through a secondary reaction to generate isosorbide, and the gaseous mixture of the isosorbide and water is distilled out synchronously; the separator is a location where water is separated from the gaseous mixture; the primary reactor, the secondary reactor and the separator are all connected with a vacuum unit; the secondary reactor is a stirred tank reactor or a molecular distiller.

In one embodiment of the application, the secondary reactor is a location for separating isosorbide from the gaseous mixture.

In one embodiment of the application, the separator comprises at least one tubular reactor, the tubular reactor comprising a conduit and a temperature control jacket disposed within the conduit.

In one embodiment of the application, the primary reactor is a stirred tank reactor, and a bottom valve for guiding the discharge or transfer of materials is arranged at the bottom of the stirred tank reactor.

In one embodiment of the application, the apparatus further comprises a buffer tank connected between the separator and the vacuum unit.

In an embodiment of the present application, when the secondary reactor is a molecular distiller, the secondary reactor is provided with a feed inlet, a heavy component discharge port, a secondary heavy component discharge port and a light component discharge port, the feed inlet is connected with the discharge port of the primary reactor, and the light component discharge port is connected with the gas inlet of the separator.

In one embodiment of the application, the device further comprises a product tank and a kettle residual tank, wherein the product tank is connected with the secondary heavy component discharge port through a pipeline; the kettle residual tank pipeline is connected with the heavy component discharge port.

In one embodiment of the application, the device further comprises a water receiving tank, and the water receiving tank is connected with the water outlet of the separator through a pipeline.

In one embodiment of the application, a liquid storage tank is connected to the liquid outlet of the buffer kettle.

In an embodiment of the application, the apparatus further comprises a feeding unit.

In one embodiment of the application, the feeding unit comprises a sorbitol metering pump and a p-toluenesulfonic acid metering pump.

The beneficial technical effects of the utility model are as follows:

(1) The device utilizes the secondary reactor to react and generate the isosorbide and synchronously distill out, so that the isosorbide can be quickly distilled out after being generated, excessive dehydration of the isosorbide is avoided, and furthermore, the isosorbide synthesized by the device has high yield and good quality, and the obtained kettle residue has good fluidity and can be recycled without influencing the feeding of the next batch so as to continuously carry out dehydration reaction. Therefore, the device can realize continuous production of the isosorbide.

(2) The application can use a molecular distiller to replace a traditional dehydration reactor, and can be used as a place for dehydrating 1, 4-sorbitan through a secondary reaction to generate isosorbide and synchronously distilling out a gaseous mixture of the isosorbide and water, and a place for separating the isosorbide from the gaseous mixture, so that the reaction time is further shortened, the production efficiency is improved, and the energy consumption is reduced; and the residue of the heavy component and the isosorbide product of the secondary heavy component are automatically separated by a molecular distiller, so that the separation efficiency is high, and the obtained product has high content.

It is to be understood that both the foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the application as claimed.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present utility model, the drawings that are needed in the embodiments will be briefly described below, it being understood that the following drawings only illustrate some embodiments of the present utility model and therefore should not be considered as limiting the scope, and other related drawings may be obtained according to these drawings without inventive effort for a person skilled in the art.

FIG. 1 is a schematic view of an apparatus for continuously producing isosorbide according to an exemplary embodiment of the present application;

FIG. 2 is a schematic diagram of an apparatus for continuously producing isosorbide according to an exemplary embodiment of the present application;

Fig. 3 is a schematic view of an apparatus for continuously producing isosorbide according to another exemplary embodiment of the present application.

Reference numerals

100: A sorbitol metering pump; 110: a p-toluenesulfonic acid metering pump; 120: a stirred tank reactor; 130: a product tank; 140: a water receiving tank; 150: a vacuum unit; 160: a first tubular reactor; 170: a second tubular reactor; 121: a stirrer; 122: a bottom valve; 200: a molecular distiller; 201: a kettle residue tank; 210: a buffer kettle; 211: a liquid storage tank; 220: a condenser; 123: and (3) a valve.

Detailed Description

Further advantages and effects of the present utility model will become readily apparent to those skilled in the art from the disclosure herein, by referring to the accompanying drawings and the preferred embodiments. The utility model may be practiced or carried out in other embodiments that depart from the specific details, and the details of the present description may be modified or varied from the spirit and scope of the present utility model. It should be understood that the preferred embodiments are presented by way of illustration only and not by way of limitation.

It should be noted that the illustrations provided in the following embodiments merely illustrate the basic concept of the present utility model by way of illustration, and only the components related to the present utility model are shown in the drawings and are not drawn according to the number, shape and size of the components in actual implementation, and the form, number and proportion of the components in actual implementation may be arbitrarily changed, and the layout of the components may be more complicated.

It should be noted that all directional indicators (such as up, down, left, right, front, and rear … …) in the embodiments of the present utility model are merely used to explain the relative positional relationship, movement, etc. between the components in a particular posture (as shown in the drawings), and if the particular posture is changed, the directional indicator is changed accordingly.

In the present utility model, unless specifically stated and limited otherwise, the terms "connected," "affixed," and the like are to be construed broadly, and for example, "affixed" may be a fixed connection, a removable connection, or an integral body; can be mechanically or electrically connected; either directly or indirectly, through intermediaries, or both, may be in communication with each other or in interaction with each other, unless expressly defined otherwise. The specific meaning of the above terms in the present utility model can be understood by those of ordinary skill in the art according to the specific circumstances.

Furthermore, descriptions such as those referred to as "first," "second," and the like, are provided for descriptive purposes only and are not to be construed as indicating or implying a relative importance or implying an order of magnitude of the indicated technical features in the present disclosure. Thus, a feature defining "a first" or "a second" may explicitly or implicitly include at least one such feature. In addition, the meaning of "and/or" as it appears throughout is meant to include three side-by-side schemes, for example, "a and/or B", including a scheme, or B scheme, or a scheme that is satisfied by both a and B. In addition, the technical solutions of the embodiments may be combined with each other, but it is necessary to base that the technical solutions can be realized by those skilled in the art, and when the technical solutions are contradictory or cannot be realized, the combination of the technical solutions should be considered to be absent and not within the scope of protection claimed in the present utility model.

Currently, existing isosorbide production units typically include a reactor, a first condenser, a product receiving tank, a second condenser, a water recovery tank, and a vacuum pump assembly connected in series. The raw materials and the catalyst are subjected to a first dehydration reaction and a second dehydration reaction in a reactor, two molecules of water are removed to generate isosorbide, the isosorbide is separated by a first condenser, and an isosorbide product is collected by a product receiving tank. The reactor, the first condenser and the second condenser are respectively connected with a temperature control system. The above-mentioned apparatus can improve the yield and content of isosorbide product to some extent, but the above-mentioned apparatus does not consider the way of removing kettle residues such as single dehydration impurity, carbide, oligomer, etc., and the efficiency of this apparatus separation kettle residue and isosorbide is low. After one isosorbide synthesis, the reactor needs to be cleaned, and after the kettle residue is removed, the next isosorbide synthesis batch is performed. In addition, the device takes a long time to synthesize the isosorbide, and high-efficiency continuous synthesis of the isosorbide cannot be realized.

In view of the above problems, the present utility model provides an apparatus for continuously producing isosorbide, comprising a primary reactor, a secondary reactor, a separator, and a vacuum unit 150 sequentially arranged along the synthesis direction of isosorbide, wherein the primary reactor is a site where molten sorbitol and p-toluenesulfonic acid are mixed and sorbitol is dehydrated through a primary reaction under a preset temperature and a first vacuum degree to obtain 1, 4-sorbitan and isosorbide; the secondary reactor is a place for keeping the preset temperature unchanged, dehydrating the 1, 4-sorbitan to generate the isosorbide through a secondary reaction under the condition of a second vacuum degree, and synchronously steaming out a gaseous mixture of the isosorbide and water; the separator is a location where water is separated from the gaseous mixture; the primary reactor, the secondary reactor and the separator are all connected with a vacuum unit 150; the secondary reactor is a stirred tank reactor or molecular still 200.

In some embodiments, the primary reactor is a stirred tank reactor 120, and a bottom valve 122 for guiding the discharge or transfer of the materials is arranged at the bottom of the stirred tank reactor 120, and when the materials are guided to be discharged, the materials are residue; when the material transfer is directed, the material is 1, 4-sorbitan and isosorbide.

Specifically, sorbitol and p-toluenesulfonic acid are put into a stirred tank reactor 120, and mixed uniformly by a stirrer 121 provided in the stirred tank reactor 120 to achieve a sufficient dehydration reaction. Preferably, a temperature sensor may be further disposed in the stirred tank reactor 120 of this embodiment, for detecting and feeding back the real-time temperature in the stirred tank reactor 120. The stirred tank reactor 120 of this embodiment may also be provided with a pressure sensor for detecting and feeding back the real-time vacuum level in the stirred tank reactor 120.

In some embodiments, the apparatus of the present embodiment may further comprise a control unit in communication with the stirred tank reactor 120, the molecular still 200, the separator, the vacuum unit 150, respectively, for regulating the temperature of the stirred tank reactor 120, the molecular still 200, and the separator. The control unit of this embodiment may be installed on the outer wall of the stirred tank reactor 120, so that the operator can control the equipment in real time. The control unit may be a controller such as an operable control panel. Or the control units can be independently arranged, can realize remote control and automatic control, and can be controllers such as a PLC controller and the like.

In some embodiments, the secondary reactor is a stirred tank reactor 120 or a molecular still 200.

In some embodiments, the separator comprises at least one tubular reactor comprising a conduit, and a temperature-controlled jacket disposed inside the conduit.

In some embodiments, the specific structure of the device for synthesizing isosorbide of the present utility model is one of the following structures:

first, as shown in fig. 1, the apparatus includes a feed unit, and a stirred tank reactor 120, a first tubular reactor 160, a product tank 130, a second tubular reactor 170, a water receiving tank 140, and a vacuum unit 150, which are sequentially disposed in a reaction direction, wherein the stirred tank reactor 120, the first tubular reactor 160, and the second tubular reactor 170 are all connected to the vacuum unit 150.

Specifically, the feeding unit is used for feeding materials into the primary reactor, and comprises a sorbitol metering pump 100 and a p-toluenesulfonic acid metering pump 110. The sorbitol metering pump 100 and the p-toluenesulfonic acid metering pump 110 are powder material metering and conveying pumps.

Specifically, the stirred tank reactor 120 is a pressure-resistant tank and is equipped with a constant temperature heating jacket, a stirrer 121, a temperature sensor, and a bottom valve 122 for guiding the discharge of the tank residue is provided at the bottom thereof. In this configuration, the stirred tank reactor 120 serves as a primary reactor and a secondary reactor, and two dehydration reactions of sorbitol are performed in the stirred tank reactor 120.

Specifically, the vacuum degree of the stirred tank reactor 120 is regulated and controlled by the vacuum unit 150, so that the vacuum degree can meet the first vacuum degree or the second vacuum degree in different dehydration reaction stages. The vacuum unit 150 of the present invention may be a high power vacuum pump assembly.

In particular, the separator of the present invention comprises a first tubular reactor 160 for separating isosorbide from a gaseous mixture, and a second tubular reactor 170 for separating water from the gaseous mixture. The first tubular reactor 160 and the second tubular reactor 170 are both tubular structures, and comprise a pipeline and a temperature control jacket arranged in the pipeline, wherein the temperature control jacket can be jacket temperature control equipment matched with a reaction kettle, and the like.

Specifically, the first tubular reactor 160 is controlled to a temperature of 60 to 70 ℃, preferably 60 ℃, to ensure that the water vapor is not cooled into the product tank 130; the second tubular reactor 170 is controlled to a temperature of 0 to 10 c, preferably 5 c, to ensure that all water vapor is condensed into the water receiving tank 140 without entering the vacuum unit 150.

Specifically, sorbitol is dehydrated by primary reaction and secondary reaction in the stirred tank reactor 120 under the catalysis of p-toluenesulfonic acid to generate isosorbide, and a gaseous mixture of isosorbide and water is distilled out synchronously, the gaseous mixture is firstly passed through the first tubular reactor 160, the product tank 130 of isosorbide for pressure resistance is separated, at this time, only water vapor remains in the gaseous mixture, the water vapor is condensed into water through the second tubular reactor 170, and the water is collected by the water receiving tank 140.

Specifically, when isosorbide is no longer distilled off, the bottom valve 122 is opened while hot, and the residue of the kettle is discharged, which includes 2, 5-position, 1, 6-position, 2, 6-position single dehydrated impurities, carbides, oligomers, humins, or the like. After the residue is discharged, the mixture is continuously fed into the stirred tank reactor 120 to synthesize isosorbide in the next batch, thereby realizing continuous production.

Specifically, the feeding unit can be in communication connection with the control unit and controlled by the control unit to realize accurate feeding.

The second, as shown in fig. 2, is different from the first device structure in that:

The isosorbide synthesizing device comprises a feeding unit, a stirred tank reactor 120, a molecular distiller 200, a condenser 220 and a vacuum unit 150 which are sequentially arranged along the reaction direction, wherein the stirred tank reactor 120, the molecular distiller 200 and the condenser 220 are connected with the vacuum unit 150. In this configuration, the tubular reactor is a condenser 220.

Specifically, to further shorten the reaction time, the stirred tank reactor 120 of this embodiment is directly connected to the molecular still 200. The secondary reactor in this configuration may also serve as a location for separating isosorbide from the gaseous mixture.

In the device, after the feeding unit feeds, the primary reaction dehydration is carried out in the stirred tank reactor 120 to generate 1, 4-sorbitan and isosorbide; the 1, 4-sorbitan secondary reaction is carried out in the molecular still 200 to dehydrate to form isosorbide, and the gaseous mixture of isosorbide and water is distilled out simultaneously. The molecular still 200 may be a commercially available molecular still 200.

Specifically, in the present apparatus, the discharge port of the stirred tank reactor 120 is connected to the feed port of the molecular still 200 through a pipe, and a bottom valve 122 is disposed on the pipe between the discharge port and the feed port, and the bottom valve 122 is a valve 123 for transferring 1, 4-sorbitan and isosorbide.

Specifically, sorbitol and p-toluenesulfonic acid are subjected to primary reaction dehydration in the stirred tank reactor 120, the temperature of the stirred tank reactor 120 is controlled by a control unit, and the vacuum unit 150 is controlled to apply a first degree of vacuum to the stirred tank reactor 120. In the primary reaction process, the valve 123 is kept closed all the time, and when the isosorbide content in the reaction system is detected to be about 50%, the control unit controls the valve 123 to be opened and controls the opening and closing degree of the valve 123 so as to achieve the purpose of slowly discharging materials into the molecular still 200.

Specifically, the molecular distiller 200 in the device can be a wiped film molecular distiller 200, the separation efficiency is high, the retention time of distilled materials (isosorbide) at the operation temperature is short, the thermal decomposition risk is low, the distillation process can be continuously carried out, and the production capacity is high. Preferably, one possibility is that the control unit controls the flow-out of the material with a scratch residence time of more than 1h, in order to obtain a high yield and content of isosorbide.

Specifically, the present apparatus shortens the reaction time by using the molecular still 200, and improves the separation efficiency, thereby improving the synthesis efficiency. Because the boiling points of isosorbide and the residue are different, the molecular still 200 separates the isosorbide and the residue and then collects the isosorbide and the residue through different discharge ports. Preferably, the molecular distiller 200 is provided with a feed inlet, a heavy component discharge outlet, a secondary heavy component discharge outlet and a light component discharge outlet, wherein the feed inlet is connected with the discharge outlet of the stirred tank reactor 120, and the light component discharge outlet is connected with the gas inlet of the separator. The device also comprises a product tank 130 and a kettle residual tank 201, wherein the product tank 130 is connected with a secondary heavy component discharge port through a pipeline; the residual tank 201 is connected with the heavy component outlet through a pipeline. Wherein the heavy component is residue, and the secondary heavy component is isosorbide product.

In particular, the device is suitable for catalyzing sorbitol to dehydrate and synthesize isosorbide by using a small amount of acid catalyst. In the device, the isosorbide can be steamed out in a short time after being generated, so that the duty ratio of a small amount of acid catalyst in a reaction system is improved, the concentration of the sorbitol in the reaction system is reduced and exchanged, and further the dehydration reaction of the sorbitol is promoted; meanwhile, as the reaction to generate the isosorbide and the distillation to distill out the isosorbide are carried out simultaneously, the combination of the isosorbide and the active center of the catalyst is reduced, and the excessive dehydration of the isosorbide is reduced. Therefore, the kettle residue generated in the synthesis process of the device can not generate serious carbonization phenomenon, has good fluidity and can flow out from the heavy component discharge port. Therefore, the residue of the kettle cannot remain in the device to influence the reaction of the next batch of materials, and the device can continuously synthesize the isosorbide.

Specifically, the molecular still 200 also distills out the light components synchronously and delivers the light components to the condenser 220 through the light components outlet for the condenser 220. The light component is water vapor.

Specifically, the apparatus further includes a water receiving tank 140, and the water receiving tank 140 is pipe-connected to the water outlet of the condenser 220. When the light components are subjected to the condenser 220, the control unit regulates the temperature of the condenser 220 so that the water vapor is condensed into water, which is collected in the water receiving tank 140.

The third type, as shown in fig. 3, is different from the second type of device in that:

The apparatus further comprises a buffer tank 210, the buffer tank 210 being connected between the condenser 220 and the vacuum unit 150. The gas inlet pipe of the buffer tank 210 is connected to the gas inlet pipe of the condenser 220, and the gas outlet pipe of the buffer tank 210 is connected to the vacuum unit 150. The liquid outlet of the buffer kettle 210 is also connected with a liquid storage tank 211.

Specifically, buffer tank 210 prevents excessive cycling of the vacuum pump in vacuum unit 150, primarily by providing a vacuum "reservoir," the basic principle of which is to utilize hold-up (volume) to provide a smoother vacuum level operation. In the embodiment, the buffer kettle 210 is used for buffering pressure, providing a gas-liquid separation function and preventing materials from flowing back into the vacuum unit 150; providing a condensing function, avoiding the gases in the stirred tank reactor 120, the molecular distiller 200, and the condenser 220 from directly entering the vacuum unit 150, thereby reducing the failure rate of the vacuum unit 150 and improving the service life of the vacuum unit 150.

Specifically, the vacuum unit 150 is used to provide a vacuum source. In the process of controlling the vacuum degree of the buffer vessel 210, the vacuum unit 150 is selected according to the vacuum degree requirement and the volume size of the buffer vessel 210.

In some embodiments, the present embodiments provide a method for continuous synthesis of isosorbide using the apparatus of the present application:

1. Adding a proper amount of sorbitol into the stirred tank reactor 120, controlling the temperature to enable the sorbitol to be in a molten state, adding p-toluenesulfonic acid, controlling the temperature to be 130-170 ℃, controlling the vacuum degree to be 1500Pa, and dehydrating. After 1 hour, the isosorbide content in the reaction system was detected to be about 50%.

2. The valve 123 is controlled to be opened, so that the 1, 4-sorbitan and the isosorbide slowly enter the molecular distiller 200 for dehydration reaction, the temperature of the molecular distiller 200 is controlled to be 130-170 ℃, the vacuum degree is controlled to be less than 200Pa (150 Pa for example), and the retention time of the scraped film of the material is controlled to be longer than 1h for outflow.

3. The bottoms are received by bottoms tank 201, the isosorbide product is received by product tank 130, and the water is collected by water receiving tank 140. When no more product is distilled off, the stirred tank reactor 120 is charged with material for the next batch of product synthesis.

The above embodiments are merely illustrative of the principles of the present utility model and its effectiveness, and are not intended to limit the utility model. Modifications and variations may be made to the above-described embodiments by those skilled in the art without departing from the spirit and scope of the utility model. Accordingly, it is intended that all equivalent modifications and variations of the utility model be covered by the claims, which are within the ordinary skill of the art, be within the spirit and scope of the present disclosure.

Claims (10)

1. The device for continuously producing the isosorbide is characterized by comprising a first-stage reactor, a second-stage reactor, a separator and a vacuum unit which are sequentially arranged along the synthesis direction of the isosorbide, wherein the first-stage reactor is a place where the sorbitol is dehydrated through a first-stage reaction to obtain the 1, 4-sorbitan and the isosorbide; the secondary reactor is a place where the 1, 4-sorbitan is dehydrated through a secondary reaction to generate isosorbide, and the gaseous mixture of the isosorbide and water is distilled out synchronously; the separator is a location for separating water from the gaseous mixture; the primary reactor, the secondary reactor and the separator are all connected with the vacuum unit, and the secondary reactor is a stirred tank reactor or a molecular distiller.

2. The apparatus for continuous production of isosorbide according to claim 1, characterized in that the separator comprises at least one tubular reactor comprising a pipe and a temperature-controlling jacket provided inside the pipe.

3. The apparatus for continuously producing isosorbide according to claim 1, wherein the primary reactor is a stirred tank reactor, and a bottom valve for guiding the discharge or transfer of the material is provided at the bottom of the stirred tank reactor.

4. The apparatus for continuous production of isosorbide according to claim 1, further comprising a buffer tank connected between the separator and the vacuum unit.

5. The apparatus for continuously producing isosorbide according to claim 1, wherein when the secondary reactor is a molecular still, the secondary reactor is provided with a feed inlet, a heavy component discharge outlet, a secondary heavy component discharge outlet and a light component discharge outlet, the separator is provided with a gas inlet, the feed inlet is connected with the discharge outlet of the primary reactor, and the light component discharge outlet is connected with the gas inlet.

6. The apparatus for continuously producing isosorbide according to claim 5, further comprising a product tank and a still residue tank, wherein the product tank is connected to the secondary heavy component outlet through a pipeline; and the kettle residual tank pipeline is connected with the heavy component discharge port.

7. The apparatus for continuous production of isosorbide according to claim 1, further comprising a water receiving tank, wherein the separator is provided with a water outlet, and wherein the water receiving tank is pipe-connected to the water outlet.

8. The apparatus for continuously producing isosorbide according to claim 4, characterized in that a liquid storage tank is connected to the liquid outlet of the buffer kettle.

9. The apparatus for continuously producing isosorbide according to claim 1, wherein the apparatus further comprises a feeding unit.

10. The apparatus for continuously producing isosorbide according to claim 9, wherein the feeding unit comprises a sorbitol metering pump, a p-toluene sulfonic acid metering pump.