JP5452552B2 - Water separation system - Google Patents

Description

  The present invention relates to a water separation system.

  2. Description of the Related Art In recent years, devices that mix fluids in fine channels, so-called microreactors, produced by microfabrication technology or the like, have been used in various fields such as biotechnology, medical field, and chemical synthesis. As a feature of the reaction using the microreactor, for example, miniaturization of the reaction system can be mentioned. Due to such downsizing of the reaction system, molecules constituting the fluid (that is, raw material molecules) are rapidly diffused and mixed, so that the surface area relative to the volume is relatively increased. As a result, since the reaction efficiency is improved as compared with the batch reaction, it is expected that the reaction time is shortened and the yield is improved.

  One chemical reaction is an equilibrium reaction. Equilibrium reaction is a reaction in a reversible reaction in which the reaction rate in the forward direction and the reaction rate in the reverse direction become equal as the reaction proceeds, and the composition ratio of the raw material and the product does not change apparently.

  One of the equilibrium reactions is a reaction that produces water as a product in addition to the target product. Specific examples include an esterification reaction in which an alcohol is reacted with a carboxylic acid. At this time, the target product is a carboxylic acid ester. Since such a reaction is an equilibrium reaction, the generated target product (for example, a carboxylic acid ester) is hydrolyzed by water simultaneously generated, and returns to the original raw material (for example, a carboxylic acid). That is, the normal reaction and the reverse reaction are proceeding simultaneously.

  In such an equilibrium reaction, when the rate of producing the target product is much higher than the rate at which the target product is hydrolyzed, there is usually no significant problem in terms of yield. However, when the former speed is slightly higher than the latter speed, it is difficult to improve the yield of the target product because it undergoes hydrolysis immediately even if the target product is generated. is there.

  Therefore, in order to improve the yield in such a reaction, it is conceivable to separate (remove) water generated simultaneously with the target product from the reaction system. By doing in this way, since a chemical equilibrium is biased in the direction which produces | generates the target product, a yield can be improved.

  As a technique for separating (removing) water from a mixed solution containing the target product and water as described above, a distillation method has been used for a long time. In recent years, in addition to distillation methods, pervaporation methods have attracted attention. The pervaporation method is a method using a separation membrane having affinity for a substance to be separated (for example, water). As a specific application method of the separation membrane, the mixed solution is arranged (or passed) on one side (supply side) of the separation membrane, and the opposite side (permeation side) is maintained at a reduced pressure. This facilitates vaporization of the liquid that has passed through the separation membrane and reached the opposite side, and allows the separation target substance to be selectively permeated and separated by the difference in permeation speed of each component.

  Various studies have been conducted on water separation technology using the pervaporation method. For example, Patent Document 1 includes a tubular separation membrane whose one end is closed and the other end is opened, and the other end of the separation membrane is watertightly fixed to a tube plate provided in a casing. A membrane module that selectively permeates a target substance in a liquid mixture or gas mixture flowing through the inside of the separation membrane, and is porous in a space formed between the inside of the casing and the outside of the separation membrane. A membrane module filled with a porous filler is described.

  Further, for example, Patent Document 2 discloses a reaction device, a membrane module that separates the contaminated component generated in the reaction device and evaporated together with the raw material component, and the evaporated contaminated component and raw material component. Heating means for heating the mixture, and circulation means for forcibly circulating the vapor of the raw material component separated by the membrane module to the liquid phase of the reactor, wherein the separation membrane of the membrane module is composed of a zeolite membrane In addition, there is described a membrane separation reaction system in which the heating means is configured to supply heat to such an extent that the raw material component and the contaminating component do not condense in the membrane module and exist in a vapor state.

JP 2007-203210 A Japanese Patent No. 446284

  In the technique described in Patent Document 1, the separation operation is performed regardless of the amount of water contained in the solution (reaction solution). Therefore, depending on the amount of water contained, the water separation efficiency may be low. Therefore, many separation operations may be required to separate water.

  Furthermore, in the technique described in Patent Document 1, it is necessary to raise the temperature to a temperature at which the solution can evaporate, so the equipment may be enlarged.

  Moreover, in the technique described in Patent Document 2, the raw material (ethanol) and water are evaporated from the reaction solution and passed through a membrane module having a separation membrane to separate water. And only the raw material after separating water is returned to the reaction vessel. Thus, in the technique described in Patent Document 2, a circulation cycle for separating water is necessary. Therefore, in this technique, the equipment may be enlarged or complicated in order to form a circulation cycle. In addition, equipment for evaporating the reaction solution may be required, and the equipment may be enlarged.

  Furthermore, the temperature control of the reaction liquid may become unstable due to the influence of the circulated raw material (returned to the reaction vessel). As a result, it becomes difficult to control the reaction in the reaction vessel, and the yield may decrease or a by-product may be generated. In addition, since the time from the evaporation of the raw material and water to the start of water separation is constant, the reaction time can be controlled only by changing the number of circulations. That is, reaction time control may be restricted.

  The present invention has been made in view of the above problems, and an object thereof is to provide a water separation system that can improve the water separation efficiency with a simple equipment configuration and can arbitrarily set the reaction time. .

  As a result of intensive studies to solve the above problems, the present inventors have found that the above problems can be solved by controlling the time until the start of water separation based on the amount of products, and have completed the present invention.

  According to the present invention, it is possible to provide a water separation system that can improve the water separation efficiency with a simple equipment configuration and can arbitrarily set the reaction time.

It is a figure which shows typically the structure of the water separation system which concerns on 1st Embodiment. It is a figure which shows typically the structure of the water separation means applied to the water separation system which concerns on 1st Embodiment. It is a figure explaining the rate constant about the reaction performed in the water separation means concerning a 1st embodiment. It is a graph which shows the speed change with respect to time. It is a figure which shows typically the structure of the water separation system which concerns on 2nd Embodiment. It is a figure which shows typically the structure of the chemical reaction progress device applied to the water separation system which concerns on 2nd Embodiment. It is a flowchart at the time of control which improves the separation efficiency of water concerning a 2nd embodiment. It is a figure which shows typically the structure of the water separation system which concerns on 3rd Embodiment. It is a graph which shows the result of an Example.

  DESCRIPTION OF EMBODIMENTS Hereinafter, embodiments for carrying out the present invention (this embodiment) will be described with reference to the drawings. However, the present embodiment is not limited to the following contents and is arbitrarily set within the scope of the present invention. It can be implemented with changes.

[1. First Embodiment]
<Configuration>
FIG. 1 is a diagram schematically illustrating a configuration of a water separation system 100 according to the first embodiment. A water separation system 100 shown in FIG. 1 is a water separation system that separates water from a product solution (reaction solution) obtained after a chemical reaction between oleic acid and methanol as raw materials. In the first embodiment, oleic acid and methanol are used as specific examples of the raw material, but the material is not limited to these as long as it is a component that generates water by a chemical reaction.

  Although details will be described later, when a chemical reaction (specifically an esterification reaction) is performed using oleic acid and methanol as raw materials, methyl oleate and water are generated. Therefore, in the present embodiment, components other than water among the components to be generated are referred to as “products”. Therefore, the product in the first embodiment is “methyl oleate”.

  As shown in FIG. 1, the water separation system 100 includes an oleic acid tank 1a, a methanol tank 1b, pumps 2a and 2b, a mixing microreactor 3, a chemical reaction progressing unit 4, a temperature controller 5, water, A separation microreactor 6, a temperature controller 7, a back pressure valve 8, a product tank 9, a cooling trap 10, a decompression device 11, and a control device 12 are provided. In FIG. 1, the solid line represents piping, and the broken line represents an electric signal line.

  The oleic acid tank 1a stores oleic acid as a raw material. The methanol tank 1b stores methanol as a raw material. Then, oleic acid and methanol are supplied from these tanks to the mixing microreactor 3 by the pumps 2a and 2b.

  The pumps 2a and 2b are constituted by, for example, a syringe pump, a manual syringe, a plunger pump, a diaphragm pump, a screw pump, or the like. Moreover, it may replace with a pump and may use the liquid feeding means which uses a water head difference.

  The mixing microreactor 3 (mixing means) mixes oleic acid and methanol. That is, in the mixing microreactor 3, oleic acid and methanol are supplied and mixed. The specific configuration of the mixing microreactor 3 is not particularly limited as long as it can rapidly mix the raw materials. For example, the channel shape of the mixing microreactor 3 may be a Y-shape, a T-shape, a shape that forms a multilayer flow, or a commercially available microreactor.

  In the first embodiment, two types of raw materials are mixed in the mixing microreactor 3, but three or more types of raw materials may be mixed. For example, when three kinds of raw materials are mixed in advance, a mixing microreactor having a flow path for mixing three kinds of raw materials can be provided instead of the mixing microreactor 3, or two kinds of raw materials can be mixed. By connecting a plurality of mixing microreactors in series, the raw materials can be mixed in order, and the desired types (number) of raw materials can be mixed.

  The degree of mixing in the mixing microreactor 3 is not particularly limited. Further, the raw materials may be mixed uniformly or may not be mixed and become non-uniform (so-called emulsified state).

  The representative length of the channel diameter of the mixing microreactor 3 is not particularly limited. However, it is preferably several mm or less from the viewpoint of making the best use of the effects of the micro-order reaction, and more preferably several tens of μm to 1 mm from the viewpoint of rapidly mixing the raw materials by molecular diffusion.

  As the material constituting the mixing microreactor 3, any material can be used as long as it does not affect the chemical reaction to be generated. Examples of such materials include stainless steel, silicone, gold, glass, hastelloy, silicone resin, and fluorine resin. In addition to these, glass lining, a metal surface coated with nickel, gold or the like, or a silicon surface oxidized may be used which has improved corrosion resistance. However, from the viewpoint of thermal conductivity and strength, it is preferable to use a metal as the material constituting the mixing microreactor 3.

  In addition, in order to perform a quick reaction in the chemical reaction progressing section 4 to be described later, a temperature controller (not shown) is installed in the mixing microreactor 3 and also in the piping connecting the mixing microreactor 3 and the pump 2a or the pump 2b. And you may make it mix at predetermined temperature. By doing in this way, the temperature increase width or temperature decrease width of the reaction solution in the chemical reaction progress part 4 can be made small, and a chemical reaction can be advanced more efficiently.

  The chemical reaction advancing unit 4 (chemical reaction advancing means) is for advancing the chemical reaction of the raw materials mixed in the mixing microreactor 3. In the first embodiment, a pipe (fine channel) that flows after the reaction solution (that is, a mixture of oleic acid and methanol) is discharged from the mixing microreactor 3 functions as the chemical reaction progressing unit 4. Therefore, the chemical reaction time can be controlled by changing the length of the pipe and the cross-sectional area of the flow path.

  Here, strictly speaking, the above-mentioned “chemical reaction time” is a period from when the raw materials are mixed in the mixing microreactor 3 to after being supplied to the water separation microreactor 6 (described later) until water begins to be separated. It will be time. However, the residence time in the mixing microreactor 3 is much shorter than the residence time in the chemical reaction progressing section 4. In fact, the chemical reaction proceeds in the water separation microreactor 6, but as described later, water is separated and the equilibrium of the chemical reaction is biased. Therefore, the water separation process has priority over the chemical reaction. It progresses. For this reason, the “chemical reaction time” in the present specification represents the time spent in the chemical reaction progressing section 4.

  The chemical reaction time may be controlled by fixing the length of the pipe and controlling the amounts of oleic acid and methanol supplied to the mixing microreactor 3. That is, since the length and inner diameter of the pipe are constant, the time for staying in the chemical reaction progressing portion 4 is shortened when a large amount of reaction solution is passed. On the other hand, when a small amount of the reaction solution is allowed to flow, the time for staying in the chemical reaction progressing section 4 becomes longer. And you may control chemical reaction time using such a relationship. In this case, the control of the feed flow rate of the raw material supplied to the mixing microreactor 3 can be performed by the control device 12 described later.

  Moreover, there is no restriction | limiting in particular in the material which comprises the chemical reaction progress part 4, For example, it can comprise using the material similar to the microreactor 3 for mixing. Further, for example, a tube made of a material such as Teflon (registered trademark) can be used. Moreover, there is no restriction | limiting in particular also in the channel diameter of the chemical reaction advancing part 4, For example, the channel diameter demonstrated in the microreactor 3 for mixing is applicable.

  The temperature controller 5 (chemical reaction temperature control means) controls the temperature at the time of the chemical reaction in the chemical reaction proceeding unit 4. The specific configuration of the temperature controller 5 is not particularly limited, and for example, a thermostatic bath, a Peltier device, a mantle heater, or the like using a fluid such as water, a water-ethanol mixed solvent, or ethylene glycol can be used. When the chemical reaction temperature is about room temperature, the temperature controller 5 may not be provided depending on the reaction heat and the thermal controllability of the microreactor.

  The water separation microreactor 6 (water separation means) separates water in the reaction solution that has flowed through the chemical reaction progressing section 4. The material and flow path diameter that constitute the water separation microreactor 6 are not particularly limited, and for example, the contents described in the mixing microreactor 3 can be similarly applied.

  Moreover, only one microreactor 6 for water separation may be provided, or two or more may be provided connected in series. These can be appropriately set according to the desired water separation time. Moreover, since the water separation microreactor 6 has a point-symmetric structure as will be described later with reference to FIG. 2, even when two or more are connected in series, a plurality of water separation microreactors 6 can be used in a minimum space. A microreactor 6 can be provided.

  Here, a specific configuration of the water separation microreactor 6 in the first embodiment will be described with reference to FIG.

  As shown in FIG. 2A, the water separation microreactor 6 has a substantially cylindrical shape, and upper and lower ends thereof are provided with flange-like members. The flange-like member has an inlet 20b into which the reaction solution flows, an outlet 20d through which the water is discharged (see FIG. 2B), and a treatment liquid after the water is separated from the reaction solution. And a discharge port 20e.

  The inside of the water separation microreactor 6 has a structure shown in FIG. As shown in FIG. 2B, the upper and lower ends of the water separation microreactor 6 have the same structure. Therefore, for simplification of description, the structure of the upper end portion and the side portion will be mainly described.

  The microreactor 6 for water separation mainly includes a first disk member 20 having inlets 20b and 20c, a second disk member 21 having protrusions 21a, a flange 22a, and a cylindrical cylindrical member 22b. 22. And the 1st disk member 20, the 2nd disk member 21, and the flange part 22a are being fixed by the screw 20a (6 pieces in FIG. 2) which penetrates them.

  In addition, packing (O-rings) 23 a and 23 b for preventing liquid leakage is provided between the first disk member 20 and the second disk member 21. Similarly, a packing 23c is provided between the second disk member 21 and the flange portion 22a.

  The separation membrane 24 separates water from the reaction solution. The separation membrane 24 in the first embodiment is a T-type zeolite membrane. The separation membrane 24 is provided so as to surround the upper and lower protrusions 21a via packing (not shown). The packing may be provided so as to be pressure-bonded to the second disk member 21 at the upper and lower ends of the separation membrane 24. By doing so, liquid leakage can be prevented.

  A space formed between the outer side of the separation membrane 24 and the inner wall surface of the cylindrical member 22b becomes a reaction solution flow path 25 through which the reaction solution flows. Further, the space formed inside the separation membrane 24 is in a state where the pressure is reduced by the pressure reducing device 11 (described later). Therefore, water becomes water vapor, passes through the separation membrane 24, and is discharged to the outside (details will be described later). That is, the space inside the separation membrane 24 becomes a water vapor flow path 26 through which water vapor flows.

  Further, the inflow port 20b and the reaction solution channel 25, and the reaction solution channel 25 and the discharge port 20e are provided through holes (not shown) provided at equal intervals in the circumferential direction of the second disk member 21. Communicate. By providing such a hole, the reaction solution can be made to flow uniformly over the entire interior of the water separation microreactor 6, and flow in a path that reduces pressure loss (so-called short circuit). This can be prevented.

  The water vapor channel 26 and the discharge port 20d are similarly communicated (as shown). Accordingly, the water contained in the reaction solution flowing through the reaction solution channel 25 through the inlet 20b passes through the separation membrane 24 and is discharged to the outside through the water vapor channel 26 and the outlet 20d. . On the other hand, the treatment liquid after water is separated from the reaction solution (that is, the liquid containing methyl oleate) is discharged to the outside through the discharge port 20.

  The inlet 20c of the water separation microreactor 6 in the first embodiment is sealed. However, as described above, the water separation microreactor 6 has a point-symmetric configuration with the vicinity of the center in the vertical direction as a symmetric point. Therefore, when it is desired to connect a plurality of water separation microreactors 6 or to use them with their vertical directions reversed, the sealing is not performed or different inlets or outlets are sealed as necessary. You may make it stop.

  Moreover, each inflow port and discharge port are comprised so that a tube (piping) can be connected. Specifically, screw holes for fitting are formed in each inlet and outlet (not shown), and by using a fitting not shown, a tube can be connected to each inlet and outlet. ing.

  Returning to FIG. 1, the overall configuration of the water separation system 100 will be described.

  The temperature controller 7 (water separation temperature control means) controls the temperature of the water separation microreactor 6. That is, the temperature at which water is separated from the reaction solution is controlled. The specific configuration of the temperature controller 7 is not particularly limited, and for example, the same one as the temperature controller 5 described above can be used.

  In the first embodiment, the temperature at the time of chemical reaction and the temperature at the time of separation of water can be set differently. For example, the temperature controllers 5 and 7 can be set so as to increase the temperature during the chemical reaction and decrease the temperature during the separation of water. Since the chemical reaction does not proceed unless the activation energy is exceeded, the reaction is more likely to proceed at a higher reaction temperature. On the other hand, since the separation membrane 24 (see FIG. 2) is usually not very heat resistant, it is preferable to separate water at a low temperature. Therefore, it is possible to set the temperature controllers 5 and 7 in this way so that the temperature at the time of chemical reaction and the temperature at the time of separation of water are different.

  The back pressure valve 8 is connected to the reaction solution flow path 25 and the discharge port 20e described with reference to FIG. By providing the back pressure valve 8, the reaction solution channel 25 can be brought into a pressurized state, and vaporization of methanol having a low boiling point can be prevented. As a result, the differential pressure between the reaction solution channel 25 and the water vapor channel 26 increases, and the separation of water by the separation membrane 24 can be promoted. However, if the set temperatures by the temperature controllers 5 and 7 are both set sufficiently lower than the boiling points of oleic acid and methanol, the back pressure valve 8 can be omitted.

  The product tank 9 is a tank for storing a treatment liquid containing methyl oleate generated by a reaction between oleic acid and methanol. The specific structure of the product tank 9 is not particularly limited, and can be the same structure as the oleic acid tank 1a and the methanol tank 1b, for example. Further, a tank for separating and collecting unreacted oleic acid and methanol may be provided.

  The cooling trap 10 is connected to the water vapor channel 26 and the discharge port 20d described with reference to FIG. That is, the water separated in the water separation microreactor 6 and discharged to the outside as water vapor is cooled in the cooling trap 10. Thereby, the vaporized water (water vapor) is changed to liquid water, and the separated water can be easily recovered.

  The decompression device 11 maintains the water vapor channel 26 under reduced pressure. By providing the decompression device 11, the separation of water by the separation membrane 24 is promoted. The specific configuration of the decompression device 11 is not particularly limited, and any decompression device may be used.

  The control device 12 controls the chemical reaction time in the chemical reaction progress unit 4. Specifically, the control device 12 controls the pumps 2a and 2b to control the liquid feed flow rate of the raw material to the mixing microreactor 3. Thereby, as described above, the chemical reaction time is controlled. At this time, the control device 12 controls the liquid feed flow rate of the raw material based on the ratio of the product in the processing liquid flowing into the product tank 9. That is, feedback control is performed.

  Specifically, the chemical reaction time is shortened when the amount of the product (methyl oleate) in the treatment liquid is large, and the chemical reaction time is lengthened when the amount of the product is small. In other words, when the amount of methyl oleate discharged from the chemical reaction progressing portion 4 is large, the chemical reaction time in the chemical reaction progressing portion 4 is shortened, and the amount of methyl oleate discharged from the chemical reaction progressing portion 4 is reduced. When the number is small, control is performed to lengthen the chemical reaction time in the chemical reaction proceeding section 4.

  The reason for performing such control will be described. Since the control device controls the flow rate of the raw material as described above, the amount of methyl oleate produced can be predicted. Then, the predicted amount of production is compared with the amount of methyl oleate actually produced, and if the amount is smaller than the predicted amount, it is determined that a further chemical reaction is possible, and the chemical reaction time is increased. To do. By doing in this way, methyl oleate and water can be generated further.

  On the other hand, if the predicted amount of methyl oleate produced is approximately the same as the amount of methyl oleate actually produced, the amount of methyl oleate produced will not increase even if the chemical reaction time is increased further. Judgment and control to gradually shorten the chemical reaction time. By such control, waste of chemical reaction time can be eliminated.

  The method for measuring the amount of methyl oleate produced is not particularly limited. For example, density, refractive index, FT-IR (Fourier Transform-Infrared), UV (Ultraviolet), HPLC (High Performance) It can be measured using Liquid Chromatography (liquid chromatography), GC (Gas Chromatography; gas chromatography) or the like.

  The control device 12 also has a function of controlling the driving of the temperature controllers 5 and 7. That is, when the set temperature of the temperature adjusters 5 and 7 is input to the control device 12, the control device 12 controls the temperature adjusters 5 and 7 so that the set temperature is reached.

  The control device 12 is realized by, for example, a CPU (Central Processing Unit), a sequencer, and the like.

<Effect>
Next, the effect in the water separation system 100 is demonstrated, referring FIG.3 and FIG.4.

As shown in FIG. 3, on the supply side of the separation membrane 24 (that is, the reaction solution channel 25), the equilibrium reaction proceeds with the reaction rate constant k ₁ and the reverse reaction with the reaction rate constant k ₋₁ . . More strictly, the reaction proceeds immediately after mixing the raw materials until the methyl oleate is isolated, but here, for convenience of explanation, the reaction is limited to the reaction in the water separation microreactor 6. Then, the liquid water on the supply side is reduced in pressure to become water vapor and permeates the separation membrane 24 and reaches the permeation side (that is, the water vapor channel 26). Permeation rate constant in water is transmitted through the separating membrane 24 (i.e. separation rate constant) and k _2.

  As shown in FIG. 4, the longer the reaction time, the lower the reaction rate of the positive reaction (positive reaction rate) depending on the remaining amount of raw material. Moreover, since reaction progresses, so that reaction time becomes long, the quantity of the water which exists in a reaction system will increase. On the other hand, the separation rate of water by the separation membrane 24 increases as the amount of water in the reaction solution increases. Considering these facts, if the reaction time has passed sufficiently, the amount of water present in the reaction system increases, so that the water separation rate increases.

  However, in the case of an equilibrium reaction, the reverse reaction proceeds simultaneously with the normal reaction, and on the contrary, the reaction rate of the reverse reaction increases as the reaction time increases. Therefore, even if the reaction time is simply secured for a long time, if a certain amount of time elapses, the reaction rate of the normal reaction becomes the same as the reaction rate of the reverse reaction, and the reaction is difficult to proceed. In other words, the water generation rate gradually decreases, and the amount of water present in the reaction system reaches a peak. Therefore, as in the water separation system 100, by appropriately setting the reaction time according to the amount of product, high water separation efficiency (that is, high yield) and reduction in wasted time until the start of water separation. Can be planned. Moreover, since the reaction liquid is not circulated, the equipment can be prevented from becoming complicated and large. Furthermore, since temperature control of the reaction liquid can be performed stably, generation of by-products can be suppressed.

[2. Second Embodiment]
Next, a water separation system 200 according to the second embodiment will be described with reference to FIG. The same means (members) as those in the water separation system 100 shown in FIG. 1 are denoted by the same reference numerals, and detailed description thereof is omitted.

<Configuration>
As shown in FIG. 5, in the water separation system 200, the chemical reaction progress unit 4 includes three chemical reaction progress devices 131, 132, 133 and three flow path control means 141, 142, 143. The structure of the chemical reaction progress device 13 is shown in FIG.

  The chemical reaction advancing device 13 has a fine channel 13b of a predetermined length embedded in the base material 13d. As shown in FIG. 6A, one end of the fine channel 13b is opened as an inflow port 13a on the front surface side, and the other end is opened as a discharge port 13c on the back surface side. Accordingly, the reaction solution flowing in from the inflow port 13a flows through the fine channel 13b and is discharged from the discharge port 13c.

  Although there is no restriction | limiting in particular as a material which comprises the chemical reaction progress device 13, For example, the material similar to the microreactor 3 for mixing mentioned above can be used. Further, the representative length of the channel diameter of the fine channel 13b constituting the chemical reaction advancing device 13 is not particularly limited, but can be the same as the channel diameter of the mixing microreactor 3 described above, for example.

  Furthermore, the channel shape of the fine channel 13b is not limited to the shape shown in FIG. 6A, and may be, for example, a linear shape or a spiral shape. Moreover, it is good also as a different flow path shape for every chemical reaction progress device 13. FIG. Further, some of them may be the same and the remaining portions may be different. However, from the viewpoint of making the heat removal performance of the chemical reaction advancing device 13 uniform and making it easier to control the chemical reaction, it is preferable that all the chemical reaction advancing devices 13 have the fine flow path 13b having the same shape. In addition, the chemical reaction progress device 13 may have an integrally molded structure or a structure that can be disassembled.

  In addition, the position of the inflow port 13a and the position of the discharge port 13c are provided so as to be point-symmetric with respect to the longitudinal center of the chemical reaction progress device 13 as a symmetric point. And by providing the inlet 13a and the outlet 13c in this way, the length of the fine channel 13b can be easily changed by simply overlapping as shown in FIG. 6B. In addition, two or more chemical reaction progress devices 13 can be connected with a minimum dead volume.

  Furthermore, fitting holes (not shown) are formed in the inlet 13a and the outlet 13c. Therefore, a tube can be connected to the inflow port 13a and the discharge port 13c by using a fitting (not shown).

In the water separation system 200 shown in FIG. 5, one chemical reaction advancing device 13 is connected to each other via the flow path control means 14. The control device 12 switches the flow path control means 14 so that the number of chemical reaction progress devices 13 through which the reaction solution flows can be changed. Therefore, by configuring the chemical reaction progressing portion 4 in this way, the length of the fine flow path 13b can be easily changed, and the time of the chemical reaction can be easily controlled.

  Specifically, for example, when it is desired to flow through one chemical reaction progress device 13 (131), the flow rate control means 141 and 143 are controlled so that the mixture does not reach the chemical reaction progress devices 132 and 133. That's fine. Similarly, when it is desired to flow through the two chemical reaction progress devices 13 (two of 131, 132, 133) or three chemical reaction progress devices 13 (131, 132, 133), the flow path control means It can be easily changed by controlling 14. That is, by controlling the flow path control means 14, the length of the fine flow path 13b that flows can be easily changed.

  In addition, as the flow path control means 14, a valve may be provided in each flow path, and the flow path through which the flow passes may be controlled by controlling those valves. Further, in FIG. 5, a plurality of chemical reaction progress devices 13 are shown connected in series. However, only one chemical reaction progress device 13 may be connected.

<Control method>
Next, a control method in the water separation system 200 shown in FIG. 5 will be described with reference to FIG. Note that the control in the flowchart shown in FIG. Whether or not the water separation efficiency has been improved is determined by a change in the amount of methyl oleate produced. That is, since the stoichiometric ratio in the amount of methyl oleate and water produced is 1: 1, the improvement in the amount of methyl oleate produced is due to the separation efficiency of water (more specifically, the production of water). Efficiency).

  After step S102, a study for improving the water separation efficiency is started (step S101). First, when oleic acid and methanol are mixed at a predetermined flow rate (that is, a predetermined reaction time) set in advance (step S102), a chemical reaction is started to generate methyl oleate and water. The separation efficiency of water is calculated from the amount of methyl oleate produced at this time and compared with the theoretical efficiency. As a result, when it is determined that the water separation efficiency is improved (that is, good) (Yes at Step S103), the examination is finished as the reaction time is optimized (Steps S110 and S111), and the conditions are Operation continues at.

  On the other hand, if the water separation efficiency is not improved in step S103 (S103, No), and if the flow rate of oleic acid and methanol can be changed (Yes in step S104), the pumps 2a, 2b are turned on. Step S102 and step S103 are repeated by controlling and changing the flow rate. If it is impossible to change the flow rate of the liquid (Step S104, No; for example, when the pumps 2a and 2b are already operated at the maximum output to increase the flow rate of the liquid), the chemical reaction proceeds The device 13 is set (step S105).

  Specifically, the flow path control means 14 is controlled to determine the number of chemical reaction progress devices 13 that flow. As a result, the chemical reaction time is set again. When the setting of the chemical reaction advancing device 13 is completed and it is determined that the water separation efficiency is good as in Step S103 (Yes in Step S106), the examination is completed as the reaction time is optimized. (Steps S110 and S111), and the operation is continued under the conditions.

  In step S106, when the water separation efficiency is not good (step S106, No), the number of chemical reaction progressing devices 13 to be passed is changed (step S107, Yes), and steps S105 and S106 are repeated. On the other hand, when it is impossible to change the chemical reaction advancing device 13 in step S107 (step S107, No; for example, when all the chemical reaction advancing devices 13 have already been used to increase the chemical reaction time) ), The temperature controller 7 is controlled to change the water separation temperature (step S108). Then, it is determined whether or not the water separation efficiency has been improved (step S109). If the water separation efficiency has been improved, the study ends (step S109 / Yes, step S110, step S111).

  When improvement of separation efficiency is not recognized in Step S109 (Step S109, No), it is examined whether the separation temperature of water can be changed (Step S112). If it can be changed, Step S108 and Step S109 are examined. repeat. On the other hand, for example, when the temperature controller 7 is already operated at the maximum output even though it is desired to raise the separation temperature, or when the temperature limit of the separation membrane 24 has been reached, the separation temperature cannot be changed. If the reaction time can not be optimized, the examination ends (step S112 / No, step S113, step S111).

[3. Third Embodiment]
Next, a water separation system 300 according to the third embodiment will be described with reference to FIG. The same means (members) as the water separation systems 100 and 200 shown in FIGS. 1 and 5 are denoted by the same reference numerals, and detailed description thereof is omitted.

<Configuration>
In the water separation system 300, a measuring device 15 (in-line measuring device) that automatically measures the amount of the product (methyl oleate) is provided. In this example, the measuring device 15 is provided between the back pressure valve 8 and the product tank 9, but may be provided between the water separation microreactor 6 and the back pressure valve 8.

  The specific configuration of the measuring device 15 is not particularly limited, and for example, an automatic measuring device using the above-described method may be used. By providing such a measuring device 15, it is not necessary for the operator to manually measure the amount of the product in the processing liquid, and complexity of control can be avoided. Moreover, since the measured amount of product is immediately input to the control device 12, the time lag when performing the feedback control can be extremely reduced. Therefore, the water separation efficiency can be improved with higher accuracy.

  Hereinafter, although an example is given and this embodiment is described in detail, this embodiment is not limited to the following examples at all.

  Using oleic acid and methanol, the separation efficiency of water produced with methyl oleate was investigated. At this time, the water separation system 100 shown in FIG. 1 was used. Detailed conditions are shown below.

[Example 1]
<Configuration>
As methanol, a reagent special grade methanol manufactured by Wako Pure Chemical Industries, Ltd. was used. In addition, to the methanol used in the examples, concentrated sulfuric acid (manufactured by Wako Pure Chemical Industries, Ltd., reagent grade) was mixed as a catalyst, and the resulting methanol solution was used. The mixing amount of concentrated sulfuric acid was 1.6% by mass with respect to the entire methanol solution.

  As oleic acid, Wako first grade oleic acid manufactured by Wako Pure Chemical Industries, Ltd. was used. The oleic acid used in the examples was subjected to a stainless steel sieve (manufactured by ASONE) having a mesh pore of 25 μm in order to remove impurities that could be contained. By this operation, blockage of various holes such as the hole of the separation membrane 24 could be prevented.

  Further, the mixing ratio of oleic acid and methanol solution was 7.18: 1, and an excessive amount of methanol was used in order to make the reaction proceed faster. The flow rate of liquid fed to the mixing microreactor 3 was 0.898 ml / min for oleic acid and 0.125 ml / min for the methanol solution. That is, the pumps 2a and 2b were set so that the total liquid supply flow rate of the raw material supplied to the mixing microreactor 3 was 1.023 ml / min.

  Hitachi Micro Reactor System Micro Process Server MPS-α200 (manufactured by Hitachi Plant Technology Co., Ltd.) was used for feeding the raw material. MPS-α200 is a system that delivers liquid with a syringe pump. When liquid is delivered, two syringe pumps (corresponding to pumps 2a and 2b) are alternately sucked using the programmed liquid delivery mode of MPS-α200. -By repeating the discharge, a volume larger than the capacity of the syringe pump was used so that the liquid could be fed without interruption.

  As the mixing microreactor 3, a microreactor CMPS-α04 manufactured by Hitachi Plant Technology was used.

  Further, as the chemical reaction time proceeding portion 4, a fluororesin tube (GL Science Co., Ltd.) having an outer diameter of 3 mm, an inner diameter of 2 mm, and a length of 10 m was used.

  The dimensions of the water separation microreactor 6 having the structure shown in FIG. 2 are such that a T-type zeolite membrane (made by Mitsui Engineering & Shipbuilding) as a separation membrane 24 is accommodated inside a tube having an inner diameter of 16 mm. The total length of the water separation microreactor 6 was 331 mm, and the diameters of the first disk member 20, the second disk member 21, and the flange portion 22a were 40 mm. Since the outer diameter of the T-type zeolite membrane was measured by 12.3 mm and the length was 300 mm, the channel width of the reaction solution channel 25 was 2 mm or less (1.85 mm).

  In order to make the inflow port 20b, the reaction solution flow path 25, and the discharge port 21e communicate with each other, four holes having a diameter of 0.2 mm were arranged in the second disk member 21 at equal intervals in the circumferential direction. As a result, the time for the reaction solution to flow from the inlet 20b to the outlet 20e of the water separation microreactor 6 almost coincided with the theoretical value, and the liquid was appropriately passed through the holes.

  Quantification of the product (methyl oleate) and oleic acid residue was performed using HPLC (High Performance Liquid Chromatography).

<Operating conditions>
First, oleic acid and a methanol solution were supplied to a mixing microreactor 3 immersed in a constant temperature bath at 60 ° C. at a total flow rate of 1.023 ml / min to obtain a reaction solution. And this reaction solution was made to flow through the chemical reaction progress part 4 immersed in the 60 degreeC thermostat (namely, the preset temperature of the temperature controller 5 corresponded to 60 degreeC). After that, the water separation microreactor 6 immersed in a constant temperature bath of 60 ° C. (that is, the set temperature of the temperature controller 7 is equivalent to 60 ° C.) was supplied at the same flow rate, and allowed to flow through the reaction solution channel 25. . And the water in the water vapor channel 26 was vaporized and separated by depressurizing the water vapor channel 26 to −0.085 MPa by the decompression device 11. The separated water was collected in an ice-cooled cold trap 10.

  The water separation was started 31 minutes after the oleic acid and the methanol solution were mixed. That is, the reaction solution was supplied to the water separation microreactor 6 after 31 minutes had passed after mixing. Then, the water separation time was extended by the so-called “stopped flow method” in which liquid feeding was stopped for 30 minutes after 56 minutes had elapsed after mixing, and then liquid feeding was started again.

  The set temperature of a temperature controller (not shown) attached to the mixing microreactor 3 and the set temperatures of the temperature controller 5 and the temperature controller 7 were all set to 60 ° C. Although this temperature is lower than the boiling point of methanol (64.7 ° C.), there is a possibility that the raw material methanol is vaporized even if it is slightly, the contact area between the raw materials becomes small and the reaction rate becomes slow. Therefore, the back pressure valve 8 was controlled to maintain the pressure of the reaction system at 138 kPa (20 psi) or more.

[Comparative Example 1]
The chemical reaction progressing part 4 was examined in the same manner as in the above example except that it was a fluororesin tube (manufactured by GL Science) having an outer diameter of about 1.6 mm, an inner diameter of 1 mm, and a length of 0.1 m. In this case, since the chemical reaction progress part 4 is very short, the reaction solution discharged from the mixing microreactor 3 is immediately supplied to the water separation microreactor 6.

[Comparative Example 2]
As Comparative Example 2, a batch method was used. In the batch method, a T-type zeolite membrane was prepared by sandwiching the top and bottom of the membrane with silicone rubber stoppers and inserting a tube into the rubber stopper so that the inside of the membrane could be decompressed. 100 ml of oleic acid was put in a 200 ml round bottom flask immersed in a 60 ° C. thermostatic bath, and 13.9 ml of methanol solution containing concentrated sulfuric acid at a concentration of 1.6% by mass was divided into 3 times in 1 minute while stirring. A reaction solution was obtained by mixing, and the reaction was allowed to proceed while stirring.

  The length of the membrane sandwiched between the upper and lower silicone rubber plugs is 20 mm, this portion is always immersed in the reaction solution, and the membrane is infiltrated. The water inside was vaporized and separated. The separated water was collected in an ice-cooled cold trap. Water separation was performed for 3 hours, and the amount of methyl oleate produced in the reaction solution was measured.

式（１）中、［オレイン酸メチル］は反応溶液中のオレイン酸メチルのモル濃度、［オレイン酸］は反応溶液中のオレイン酸のモル濃度を表す。 [result]
FIG. 9 shows a graph of the yield with respect to the elapsed time from the start of mixing (ie, chemical reaction time). The yield is the yield of methyl oleate calculated by the following formula (1).

In formula (1), [methyl oleate] represents the molar concentration of methyl oleate in the reaction solution, and [oleic acid] represents the molar concentration of oleic acid in the reaction solution.

  As shown in FIG. 9A, in Example 1, an equilibrium state was reached with a yield of 52% before the start of water separation. However, when water separation was started, the yield increased, and the yield was sufficiently improved as compared with Comparative Example 2 which is a conventional method. In particular, when the reaction time was 85 minutes, the yield was 63%, an increase of 7% compared to Comparative Example 2.

  Moreover, as shown in FIG.9 (b) which compared the comparative examples, the comparative example 1 which does not provide the chemical reaction progress part 4 and the comparative example 2 which is the conventional batch method showed the substantially the same behavior. Although not shown, in Comparative Example 1, water separation was not observed within the reaction time of 55 minutes.

Furthermore, for Example 1 and Comparative Examples 1 and 2, rate constants k ₁ , k ₋₁ , and k ₂ (see FIG. 3) calculated based on the following formula (2) were calculated. A specific calculation formula is shown below.

表１中、「※」は水の分離が観測されなかったため、計算できなかったことを示す。 Table 1 summarizes the above results.

In Table 1, “*” indicates that water could not be calculated because no water separation was observed.

When water is separated after 31 minutes of reaction time (Example 1), when water is separated from the start of the reaction (Comparative Example 1) or batch method (Comparative Example 2), it cannot be simply compared, The water separation rate constant k ₂ was about 10 ³ times that of Comparative Example 1 and about 10 ⁸ times that of Comparative Example 2. As described above, it was revealed that water can be efficiently separated by using the microreactor for water separation and further providing the chemical reaction proceeding portion 4.

In addition, in the case of Example 1, the rate constant k ₁ of the positive reaction of water separation before the start (i.e. 31 minutes before) is larger than that of Comparative Example 1 and Comparative Example 2. Therefore, it has become clear that the chemical reaction time can be shortened by providing the chemical reaction progressing section 4.

  From the above results, it was found that according to the present embodiment, water can be efficiently separated and a high yield can be obtained in a short chemical reaction time.

3 Microreactor for mixing (mixing means)
4 Chemical reaction progress section (chemical reaction progress means)
5 Temperature controller (chemical reaction temperature control means)
6 Microreactor for water separation (water separation means)
7 Water separation temperature control means 12 Control device (control means)
13 Chemical reaction progress device 15 Measuring device (In-line measuring device)

Claims (6)

A water separation system for separating water from a product solution obtained after chemically reacting raw materials,
A mixing means for supplying and mixing the raw materials;
A chemical reaction advancing means connected downstream of the mixing means to allow a chemical reaction of the mixed raw materials to proceed;
A water separating means connected downstream of the chemical reaction advancing means for separating water generated in the chemical reaction advancing means;
Control means for controlling the chemical reaction time in the chemical reaction progress means;
With
The control means includes
When the amount of the product in the solution discharged from the chemical reaction advancing means is large, the chemical reaction time in the chemical reaction advancing means is shortened,
The water separation system is characterized in that when the amount of the product in the solution discharged from the chemical reaction advancing means is small, control is performed to lengthen the chemical reaction time in the chemical reaction advancing means. The water separation system according to claim 1,
The control means includes
A function of controlling the flow rate of the raw material supplied to the mixing means;
The water separation system is characterized in that the chemical reaction time is controlled by controlling the flow rate of the raw material supplied to the mixing means. The water separation system according to claim 1,
The chemical reaction advancing means has a fine channel,
A water separation system, wherein a chemical reaction time is controlled by changing a length of the fine channel. The water separation system according to claim 3,
The chemical reaction advancing means is constituted by a device having a fine channel of a predetermined length,
The length of the fine channel is set by connecting one or a plurality of the devices in series, and a water separation system. In the water separation system according to any one of claims 1 to 4,
Chemical reaction temperature control means for controlling the temperature during the chemical reaction;
Water separation temperature control means for controlling the temperature during water separation;
With
A water separation system characterized in that the temperature at the time of chemical reaction and the temperature at the time of separation of water are set differently. The water separation system according to any one of claims 1 to 5,
A water separation system characterized in that an in-line measuring means for measuring the amount of the product is provided.

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