JP2016059833A - Regeneration treatment of anion exchange resin catalyst for continuous production of fatty acid ester - Google Patents

Abstract

PROBLEM TO BE SOLVED: To drastically reduce an amount of solution to be used for a regeneration processing method and cost needed for regeneration processing by simplifying steps in the conventional regeneration processing method of an anion exchange resin catalyst for producing a fatty acid ester from a fat and oil.SOLUTION: In a regeneration processing method of an anion exchange resin catalyst, a new step to again feed a liquid remaining in a column in an ester exchange and adsorption process and including an unreacted oil and fat material and a product fatty acid ester to the anion exchange resin is added, an acetic acid concentration in the methanol solution to be used in a step (2) of the conventional method is heightened, and a mixed solution of water and methanol is used in place of an aqueous sodium hydroxide solution to be used in a step (3) of the conventional method, as well as discharge liquids from respective steps of regeneration processing are reused in the next regeneration processing, and so on. In a continuous production method of the fatty acid ester from fat and oil, the anion exchange resin regenerated by the method is used.SELECTED DRAWING: Figure 2

Description

The present invention relates to a method for regenerating an anion exchange resin catalyst used in a method for producing a fatty acid ester from fats and oils, a method for producing the fatty acid ester using the anion exchange resin catalyst regenerated by the regeneration method, and the like.

Fatty acid esters synthesized by transesterification of fats and alcohols have attracted attention as biodiesel fuels. Compared to conventional petroleum diesel fuel (light oil), biodiesel fuel has cleaner exhaust gas, reduced emissions of carbon monoxide, hydrocarbons, particulate matter, etc., exhaust gas It has many features such as not containing sulfur oxides and sulfates and high lubrication performance. In addition, since it can be synthesized from waste cooking oil that contributes to environmental pollution, it is also expected as an environmentally friendly waste treatment technology.

Kitagawa et al., The inventor of the present invention, has developed a fatty acid ester synthesis technology that transesterifies triglycerides contained in fats and oils at a relatively low temperature (50 ° C) with the unique idea of using an anionic resin as a heterogeneous solid catalyst. It has been pioneered (Non-Patent Document 2, Patent Document 1, Patent Document 2).

The ion exchange resin used for the production of fatty acid ester as a biodiesel fuel inevitably deteriorates the catalyst performance due to the adsorption of fatty acid residues to the resin. Therefore, the present inventor has also developed a method for regenerating the catalytic activity of the anionic resin used in the fatty acid ester continuous synthesis by washing with a weak acid solution (Patent Document 3).

JP 2006-104316 A JP 2007-297611 A JP 2007-14871 A

Biochem.Biophys.Res.Commun., 348,170 (2006) Bioresource Technol. 98,416 (2007) Bioresource Technol. 142,732 (2013)

Conventional methods for regenerating ion exchange resins used in the production of fatty acid esters, such as those described in Patent Document 3, Non-Patent Document 2, and Non-Patent Document 3, step by step several large amounts of solutions. It was necessary to supply to the plant, and the load was large both economically and environmentally.

As a result of research aimed at solving the above-mentioned problems, the present inventor has simplified the steps in the conventional method for regenerating an anion exchange resin catalyst for fatty acid ester production from fats and oils, and has By reusing the discharged liquid, it was found that the amount of solution used in the regeneration treatment method and the cost required for the regeneration treatment can be greatly reduced, and the present invention has been completed.

That is, the present invention relates to the following aspects.
[Aspect 1] A method for regenerating an anion exchange resin used in the continuous production of fatty acid esters from fats and oils, comprising the following steps:
Step (1): Methanol is supplied to the anion exchange resin, and glycerin adsorbed on the resin is eluted and recovered as a by-product;
Step (2): supplying a methanol solution of acetic acid to the anion exchange resin to exchange fatty acid residues adsorbed on the resin with acetic acid residues;
Step (3): supplying a mixed solution of sodium hydroxide in water and methanol to the anion exchange resin to exchange the acetic acid residue adsorbed on the resin with a hydroxyl group to activate the resin;
Step (5): Methanol is supplied to the anion exchange resin to elute free hydroxyl groups and sodium acetate and swell the anion exchange resin; and Step (6): discharged in the first half of step (1) In addition, the liquid containing the unreacted oil and fat in the transesterification / adsorption process is supplied again to the anion exchange resin, and the methanol supplied in the step (5) is extruded.
Said method.
[Aspect 2] The method according to aspect 1, wherein the discharged liquid in the first 60 to 80% of the step (1) is supplied as a liquid containing unreacted fats and oils in the step (6).
[Aspect 3] The method according to Aspect 1 or 2, wherein the concentration of acetic acid in the methanol solution used in step (2) is 0.8 to 1.4 mol / L.
[Aspect 4] The method according to aspect 3, wherein the concentration of acetic acid in the methanol solution used in step (2) is 1.3 mol / L.
[Aspect 5] The method according to any one of Aspects 1 to 4, wherein the methanol content in the mixed solution of water and methanol used in step (3) is 80% by volume or less.
[Aspect 6] The method according to Aspect 5, wherein the volume ratio of water and methanol in the water and methanol mixed solution used in step (3) is 2: 8.
[Aspect 7] The method according to any one of Aspects 1 to 6, wherein the effluent from step (2) is reused instead of methanol in step (1) of the next regeneration treatment method.
[Aspect 8] Any one of Aspects 1 to 7, wherein the effluent from step (5) is reused as part of a mixed solution of sodium hydroxide, methanol and water in step (3) of the next regeneration treatment method. The method according to item.
[Aspect 9] The method according to Aspect 8, wherein the effluent from step (5) is re-adjusted as a mixed solution of sodium hydroxide, methanol and water in step (3) after fine adjustment of sodium concentration and water concentration.
[Aspect 10] The method according to any one of Aspects 1 to 9, wherein the effluent from step (6) is reused as part of step (5) of the next regeneration treatment method.
[Aspect 11] A continuous process for producing fatty acid esters from fats and oils using the anion exchange resin regenerated by the method according to any one of Aspects 1 to 10 as a heterogeneous solid catalyst.
[Aspect 12] The method according to Aspect 11, wherein the transesterification and / or adsorption is continuously performed using a reactor filled with an anion exchange resin.
[Aspect 13] Transesterification reaction and / or adsorption are continuously performed using a reactor filled with at least two towers of anion exchange resin connected in series, and the reaction on the most upstream side of the at least two towers. When the catalytic activity of the anion exchange resin charged in the reactor has disappeared, the anion exchange resin is subjected to a regeneration treatment by the method according to any one of Embodiments 1 to 10, and Aspect 11 or 12 characterized in that a cycle consisting of continuing a continuous production method of fatty acid ester is repeated by connecting a reactor filled with the anion exchange resin regenerated by the method downstream. The method described in 1.
[Aspect 14] A system for carrying out the method according to any one of Aspects 11 to 13, wherein the reactor is filled with a cation exchange resin for esterifying a free fatty acid contained in an oil or fat raw material. , And at least two reactors connected in series filled with an anion exchange resin used for transesterification and / or adsorption of triglyceride contained in fats and oils connected downstream thereof, and regenerated. The system comprising a reactor filled with an anion exchange resin.

In the regeneration treatment method of the anion exchange resin catalyst of the present invention, the regeneration treatment method is simplified, and the effluent from the regeneration treatment step is reused to the maximum in the next regeneration treatment. It is possible to greatly reduce the amount of solution used and the cost required for the regeneration treatment, and it is possible to reduce the environmental load.

Furthermore, by reusing the anion exchange resin catalyst regenerated by the method of the present invention as a transesterification / adsorption resin in the continuous production of fatty acid esters from fats and oils, the fatty acid ester as the product fuel is substantially continuous. Thus, it is possible to construct a “merry-go-round system” that continuously produces product fuel from fats and oils and regenerates anion exchange resins.

The process flow of the continuous manufacturing method of the fatty acid ester from the fats and oils containing free fatty acid (FFA) by an ion exchange resin catalyst is shown. An example of the "merry-go-round system" for implementing the continuous manufacturing method of the fatty acid ester of this invention is shown. This is a system consisting of 1 column filled with cation exchange resin and 3 columns filled with anion exchange resin (2 columns are fuel production, 1 column is resin regeneration), and anion exchange resin packed in the upstream column When the activity of is completely lost, the operation is switched from mode 1 to 2 to 3. An example of the fuel manufacture profile in the continuous manufacturing method of the fatty acid ester from fats and oils is shown. The regeneration method used is the conventional method shown in Table 1, and changes in the concentration of each component in the product that flows out through two column reactors (inner diameter 5 cm, length 50 cm) packed with 0.6 kg of anion exchange resin. It is. The amount of fatty acid ester obtained in one mode is about 2.7 L from the integral of the shaded part. An example of the regeneration process profile in the regeneration process method of the conventional anion exchange resin is shown. This is a change behavior of each component concentration in the solution flowing out through one column reactor (inner diameter 5 cm, length 50 cm) packed with 0.6 kg of anion exchange resin. The result of Example 2 (1) is shown. The result of Example 2 (2) is shown. The result of comparing the regeneration processing profiles with and without reuse of the discharged liquid is shown.

A conventional method (Non-Patent Document 2) used for the regeneration treatment of an anion exchange resin catalyst used in a method for producing a fatty acid ester from fats and oils as described in Non-Patent Document 2 and Non-Patent Document 3. ) Is shown in Table 1. This method includes the following steps.
(1) supplying methanol to the anion exchange resin, eluting glycerin adsorbed on the resin and recovering it as a by-product;
(2) supplying a methanol solution of acetic acid to the anion exchange resin to exchange fatty acid residues adsorbed on the resin with acetic acid residues;
(3) An aqueous solution of sodium hydroxide is supplied to the anion exchange resin, and the resin is activated by exchanging acetic acid residues adsorbed on the resin with hydroxyl groups;
(4) supplying deionized water to the anion exchange resin to remove free hydroxyl groups and sodium acetate;
(5) Supply methanol to the anion exchange resin to swell the anion exchange resin.

Table 2 shows an outline of one embodiment of the method for regenerating an anion exchange resin according to the present invention. The main features compared with the above conventional method are as follows.

1. The liquid containing the unreacted oil raw material and the product fatty acid ester remaining in the column during the transesterification / adsorption process discharged in the first half of the step (1) is supplied again to the anion exchange resin, and the step (5 In the case where the anion exchange resin after the regeneration treatment is used for transesterification / adsorption by adding a new step (6) for extruding the methanol supplied in (3), the conventional oil and fat as seen in FIG. In the continuous production method of fatty acid ester from the product, it is possible to eliminate the operation time during which only methanol is first discharged and the fatty acid ester (product fuel) is not obtained, and the product fuel can be produced continuously.

Here, the liquid containing the unreacted fat and oil in the transesterification / adsorption process including the fat raw material and the like is obtained by using any method / means known to those skilled in the art, such as HPLC, at a suitable interval. This can be confirmed by appropriate analysis.

The first half of the step (1) varies depending on various conditions of the regeneration treatment process / system, raw oil components, etc., and is, for example, about 60 to 80% in the first half of the step (1).

2. Acetic acid concentration in the methanol solution used in step (2) of the above conventional method is set to 0.8 to 1.4 mol / L, preferably 1.3 mol / L, and the reaction is made more efficient (reduction of manufacturing cost). I planned.

3. Instead of the aqueous solution of sodium hydroxide used in step (3) of the conventional method described above, a mixed solution with methanol containing an amount of water capable of maintaining the activation reaction efficiency in step (3), that is, By using a mixed solution of water and methanol containing methanol up to about 80% by volume, preferably a mixed solution of water and methanol in a volume ratio of 2: 8 as a solvent for sodium hydroxide as described above. The amount of water used in the step (3) of the method was reduced, and the step (4) for supplying water was made unnecessary.

Furthermore, in another aspect of the method for regenerating an anion exchange resin according to the present invention, a method comprising the steps (1) to (3) and (5) shown in the above aspect, preferably further comprising a step (6 ), The waste liquid from each step of the regeneration process is reused in the next regeneration process as described below.

That is, the effluent discharged in the latter half of the step (1) is no longer substantially free of unreacted oil and is a methanol solution containing 60% by weight or more of glycerin. Turn into.

The latter half of the step (1) varies depending on various conditions of the regeneration treatment process / system, raw oil components, etc., and is, for example, about 20 to 40% in the latter half of the step (1).

Furthermore, since the effluent from step (2) is methanol containing a small amount of fatty acid liberated from the resin, it is reused instead of methanol in step (1) of the next regeneration treatment method.

Moreover, since the effluent discharged | emitted from the process (5) contains methanol, a sodium ion, and water, after adjusting a sodium concentration and a water density | concentration suitably, this is used in the process (3) of the next regeneration processing method. Reuse as a mixed solution of sodium hydroxide, methanol and water.

Further, the effluent from step (6) is reused as part of step (5) of the next regeneration process.

The present invention further relates to a continuous process for producing fatty acid esters from fats and oils using an anion exchange resin regenerated by the above regenerating method as a heterogeneous solid catalyst. In addition, the continuous manufacturing method itself of the fatty acid ester from fats and oils has already been described in the literature cited in the prior art document of this specification. The process flow is shown in FIG.

Specifically, a method in which transesterification and / or adsorption is continuously performed using a reactor filled with an anion exchange resin is preferable.

As the anion exchanger (anion exchanger), any of those known to those skilled in the art described in JP-A-2006-104316 and JP-A-2007-297611 can be used. In particular, strong basic anion exchange resins are preferred. When the anion exchange resin is classified by the degree of crosslinking or porosity, a gel type, a porous type, a high porous type and the like can be mentioned, and a porous type and a high porous type are preferable.

Incidentally, as commercially available products, for example, Diaion PA-306 (manufactured by Mitsubishi Chemical Corporation), Diaion PA-306S (same), Diaion PA-308 (same), Diaion HPA-25 (same) Dowex 1 -X2 (manufactured by Dow Chemical Company), Amberlite IRA-45 (manufactured by Organo), Amberlite IRA-94 (same), etc. can be used.

Furthermore, examples of commercially available anion exchange resins satisfying pKa of 9.8 or less include Diaion SA20A (manufactured by Mitsubishi Chemical Corporation), Diaion SA21A (same), and porous type II strong base anions. As an exchange resin, Diaion PA408 (same), Diaion PA412 (same), Diaion PA418 (same), and the like can be used. Here, the type II strong base anion exchange resin refers to the above-described anion exchange resin having a dimethylethanolammonium group.

Since a commercial product of an anion exchange resin is Cl type at the time of purchase, it is used in the present invention after being substituted with an OH group. For example, a 0.5 to 2 mol / L NaOH aqueous solution is used as the replacement agent, and the flow rate of the replacement agent is preferably about 2 to 10 ml-NaOH / min per 1 ml of anion exchange resin. The flow rate is 5 to 20 ml per 1 ml of anion exchange resin. After the substitution is completed, the resin is taken out from the column and thoroughly washed with distilled water so that the substitution agent does not remain. The pH of the resin cleaning solution is measured to confirm that it has the same pH as that of distilled water, and finally washed with a predetermined alcohol and used in the present invention.

The amount of the anion exchange resin used is usually about 0.1 to 1.0 L, preferably about 0.3 to 0.5 L as the amount of oil per 1 kg-wet of the resin.

In addition, since free fatty acids contained in the oil are adsorbed to the anion resin, when directly treating the oil containing a large amount thereof, the cation exchange is performed before contacting the oil with the anion exchange resin. It is necessary to advance the esterification reaction of the free fatty acid contained in the oil with the resin to form an adsorption-inactive ester.

As the cation exchange resin, for example, a cation resin known to those skilled in the art such as Diaion PK-208LH (manufactured by Mitsubishi Chemical Corporation) can be used.

Various conditions such as reaction time and temperature by the anion exchange resin and the cation exchange resin can be appropriately set by those skilled in the art. For example, the reaction time can be 5 minutes to 2 hours, 0 ° C. to 55 ° C., and about 1 to 10 atm.

The conditions such as the reaction time and temperature, the supply conditions such as the flow rate of the treatment liquid in the regeneration treatment method and fatty acid ester production method of the present invention are, for example, the values described in this specification and the accompanying drawings. Accordingly, those skilled in the art can appropriately set.

There is no particular limitation on the fat used as a raw material in the method for continuously producing the fatty acid ester of the method of the present invention, and natural oil (crude oil), synthetic oil, or a mixture thereof may be used. Furthermore, modified oils obtained by modifying a part of these oils by oxidation, reduction, or the like, and oil processed products containing these oils as the main component can also be used as raw materials.

For example, fatty acid oil, deodorized effluent (scum oil), etc. that are by-produced in the refining process of rice bran oil and palm oil, which are used as raw materials in the conventional method, are not usable. It is also possible to use oil in which any foreign component other than fats and oils is mixed. These foreign components are preferably removed by an appropriate means known to those skilled in the art, such as sedimentation, filtration, and liquid separation, and then used in the method of the present invention.

Further, in place of methanol used in the method of the present invention, other alcohols having a saturated linear or branched hydrocarbon skeleton having 1 to 8, preferably 1 to 5 carbon atoms may be used. Is possible. For example, ethyl alcohol, propyl alcohol, isopropyl alcohol, n-butyl alcohol, t-butyl alcohol and the like can be mentioned. These alcohols can be used alone or in admixture of two or more. In addition to acting as a reaction substrate for subjecting oils to alcoholysis (transesterification reaction), alcohols also have a solvent action for adjusting dilution and viscosity of oils.

In the continuous production method of fatty acid ester of the present invention, the transesterification and / or adsorption is continuously performed using a reactor filled with at least two towers of anion exchange resin connected in series, and the at least two towers are used. When the catalytic activity of the anion exchange resin charged in the most upstream reactor is lost, the anion exchange resin is subjected to the regeneration treatment method of the present invention, and the most downstream side of the remaining reactors. A so-called “merry-go-round system (method)” is constructed by repeating a cycle consisting of continuing a continuous production method of fatty acid esters by connecting a reactor filled with an anion exchange resin regenerated by the above method can do. An example of this is shown in FIG.

Therefore, this invention relates also to the system for enforcing the continuous manufacturing method of the fatty acid ester from such fats and oils. The system includes, for example, a reactor filled with a cation exchange resin for esterifying a free fatty acid contained in a fat raw material, and a transesterification reaction of a triglyceride contained in the fat and oil connected downstream thereof. Alternatively, it includes at least two reactors filled with an anion exchange resin used for adsorption and connected in series, and a reactor filled with an anion exchange resin to be regenerated.

In the system of the present invention, more specifically, a reactor having a reaction substrate introduction port on one side of a container (reactor) filled with a predetermined ion exchanger and a product recovery port on the other side is desirable. . Although the said container may have individually, you may have the structure formed by connecting two or more in parallel and / or in series. The shape of the container is not particularly limited, but a column is usually used. When an ion exchange resin is packed in a column and used, an embodiment using an expanded bed column packed layer having a high porosity is preferable in order to prevent the resin from swelling and being damaged. Here, an expanded bed column is used in a separation and purification method in which a target component dissolved in a fluid having a high viscosity or a solid content is adsorbed and recovered by adsorbent particles. This refers to those in which fluid is flowed upward, adsorbent particles having a large specific gravity are suspended in a stationary state, and column chromatography operation is performed while maintaining a large porosity. For example, Chemical Engineering Papers Vol. 27, No. 2 (2001) Known methods described in pages 145-148 and the like can be used. In the range where the molar ratio of oils to alcohols is large, the problem of breakage of the ion exchange resin due to swelling is likely to occur, so care is taken in designing the reactor. However, for efficient operation, an upward flow is used during a reaction / adsorption operation in which a mixture of oil and alcohol is passed, and a downward flow is used in a resin regeneration operation where the mixture of acid and alcohol is passed. Is preferably used.

EXAMPLES Hereinafter, although this invention is concretely demonstrated according to an Example, the technical scope of this invention is not restrict | limited at all by these description. The following examples were carried out according to general methods known to those skilled in the art unless otherwise specified.

[Effect of step (6) in the regeneration treatment method of the ion exchange resin of the present invention]
In step (6) of the ion-exchange resin regeneration treatment method of the present invention, a liquid containing unreacted oil raw material and product fatty acid ester remaining in the column in the transesterification / adsorption process discharged in step (1) Was supplied to the anion exchange resin, and the effect of extruding the methanol supplied in step (5) was verified under the following conditions. 1 column (diameter 5cm x length 100cm) packed with cation-exchange resin Diaion PK208LH and 2 columns (diameter 5cm x length 50cm) packed with 0.6kg-wet each of anion-exchange resin DiaionPA306S The reaction system connected in series was maintained at 50 ° C., and a raw material solution obtained by mixing crude Jatropha oil (free fatty acid content: 30 wt%) and methanol in a stoichiometric ratio was supplied at 100 cm ³ / h.

Fig. 1 shows the fuel production profile (change over time in the amount of fatty acid methyl ester (FAME), triglyceride (TG) and free fatty acid (FFA) produced) in the continuous production method of fatty acid esters from fats and oils as shown in Fig. 1. It was shown in 3.

Here, in the case where the above-described step (6) is not carried out, even if continuous production / regeneration is performed using a merry-go-round system, the profile in FIG. 3 (the portion on the horizontal axis 0-3.8, unreacted TG) The part where no is detected) is repeated. In other words, it is a semi-batch operation, and only the methanol flows out on the horizontal axis 0-0.8, and no product is obtained. That is, a product cannot be obtained in 21% of the manufacturing operation time.

On the other hand, by adding the step (6), the region on the left side from the broken line in FIG. 3 is shifted to the regeneration step, and the manufacturing process is a repetition of the portion of the horizontal axis 0.8-3.8, which is substantially continuous. Thus, it becomes possible to produce a product fuel.

When the merry-go-round system as shown in FIG. 2 is used, the regenerated column is connected to the most downstream side of the merry-go-round manufacturing column. The reaction liquid remaining in the column after the step (6) is a liquid containing the unreacted fat raw material and the product fatty acid ester in the transesterification / adsorption process discharged in the step (1) by the regeneration treatment method of the present invention. The reaction proceeds at least half or more by the regenerated ion exchange resin. Therefore, when this is returned to the regenerated column connected to the most downstream of the production, the reaction rate becomes 100% even if only one column passes, and the production of product fuel from fats and oils and the anion exchange resin It is possible to construct a merry-go-round system that performs continuous reproduction.

[Effect of mixed solution of water and methanol used in step (3) and the concentration of acetic acid in the methanol solution used in step (2) in the regeneration treatment method of the ion exchange resin of the present invention]
The following examination was performed based on the regeneration processing profile (FIG. 4) in the conventional anion exchange resin regeneration processing method (Non-Patent Document 2).

First, the fluctuation | variation of the amount of free fatty acids discharged | emitted by changing the acetic acid density | concentration in the methanol solution used at a process (2) was measured, and efficiency improvement (reduction of manufacturing cost) was examined. The result is shown in FIG.

According to it, the range of acetic acid concentration in the methanol solution used in step (2) is higher than the conventional 0.43 mol / L, for example, about 0.8 to 1.4 mol / L, preferably about When the concentration was 1.3 mol / L, the concentration of free fatty acid to be eluted (labeled “FH” or “FFA”) increased rapidly, so the total amount of acetic acid used increased but the required methanol solution As a result, the amount of the reagent used in the step (2) was reduced, and the efficiency of the reaction was improved.

Next, the influence of using a mixed solution of water and methanol in place of the aqueous solution used in step (3) of the conventional method was examined. The result is shown in FIG.

According to it, in a mixed solution of water and methanol containing methanol up to about 80%, especially in a mixed solution with a volume ratio of water and methanol of 2: 8, the free hydroxyl group concentration is about the same as that in an aqueous sodium hydroxide solution. Turned out to be maintained. Accordingly, in the step (3), by using a mixed solution of sodium hydroxide water and methanol in place of the conventional aqueous sodium hydroxide solution, the activation reaction efficiency by the hydroxyl group is substantially maintained, while the step The amount of water used in (3) was reduced, step (4) became unnecessary, and further, the time required for step (5) could be shortened.

FIG. 7 shows a regeneration processing profile obtained by adding the above improvements to the conventional anion exchange resin regeneration processing method (step (4) in the prior art is omitted). As is apparent from a comparison of this with the regeneration processing profile in the conventional anion exchange resin regeneration processing method shown in FIG. 4, while maintaining the regeneration processing efficiency comparable to that of the conventional technology, the regeneration processing cost is reduced. From the above 159.5 Yen / L-FAME (fatty acid ester), the above-mentioned improvement resulted in a remarkable effect of reducing it to 125.7 Yen / L-FAME (Table 3). In any case, the amount of fatty acid ester produced in each mode of fuel production is about 2.7 L, and the cost per 1 L of fatty acid ester can be obtained from this value.

[Effects of reusing the effluent from each process of the regeneration process in the next regeneration process]
In the improvement technology of the conventional anion exchange resin regeneration treatment method according to the present invention described in Example 2, the effect of reusing the effluent from each step of the regeneration treatment in the next regeneration treatment is further examined. did.

First, based on the effluent composition from each regeneration process step of the improved technique for the regeneration process of anion exchange resin according to the present invention (FIG. 7), the reuse rate when reused in the next regeneration process was examined. The results are shown in Table 4.

Further, the regeneration process profile and the regeneration process cost were compared in the case where the waste liquid shown in Table 4 was reused and in the case where it was not reused (Table 5). The amount of fatty acid ester produced in each mode of fuel production is about 2.7L, and the cost per 1L of fatty acid ester can be obtained from this value. As a result, the same regeneration profile was obtained for both, and it was confirmed that even when the effluent was reused, the regeneration capacity of the anion exchange resin was not substantially reduced. On the other hand, by reusing the effluent, the total amount of the solution used in the regeneration treatment method was remarkably reduced, and the production cost of the fatty acid ester could be reduced by 68.5%. In addition, the environmental burden could be reduced by reusing the discharged liquid.

According to the present invention, the cost of producing fatty acid ester for biodiesel fuel can be greatly reduced, and it can be produced at a lower cost and with less environmental load than the cost of producing commercially available light oil.

Claims (14)

A method for regenerating an anion exchange resin used in the continuous production of fatty acid esters from fats and oils, comprising the following steps:
Step (1): Methanol is supplied to the anion exchange resin, and glycerin adsorbed on the resin is eluted and recovered as a by-product;
Step (2): supplying a methanol solution of acetic acid to the anion exchange resin to exchange fatty acid residues adsorbed on the resin with acetic acid residues;
Step (3): supplying a mixed solution of sodium hydroxide in water and methanol to the anion exchange resin to exchange the acetic acid residue adsorbed on the resin with a hydroxyl group to activate the resin;
Step (5): Methanol is supplied to the anion exchange resin to elute free hydroxyl groups and sodium acetate and swell the anion exchange resin; and Step (6): discharged in the first half of step (1) In addition, the liquid containing the unreacted oil and fat in the transesterification / adsorption process is supplied again to the anion exchange resin, and the methanol supplied in the step (5) is extruded.
Said method. The method according to claim 1, wherein the discharged liquid in the first half 60 to 80% of the step (1) is supplied as a liquid containing unreacted fats and oils in the step (6). The method of Claim 1 or 2 whose acetic acid concentration in the methanol solution used at a process (2) is 0.8-1.4 mol / L. The method according to claim 3, wherein the concentration of acetic acid in the methanol solution used in step (2) is 1.3 mol / L. The method as described in any one of Claims 1 thru | or 4 whose methanol content in the water and methanol mixed solution used at a process (3) is 80 volume% or less. The method according to claim 5, wherein the volume ratio of water and methanol in the water and methanol mixed solution used in step (3) is 2: 8. The method according to any one of claims 1 to 6, wherein the effluent from step (2) is reused in place of methanol in step (1) of the next regeneration treatment method. The effluent from step (5) is reused as part of a mixed solution of sodium hydroxide, methanol and water in step (3) of the next regeneration treatment method. the method of. 9. The method according to claim 8, wherein the effluent from step (5) is reused as a mixed solution of sodium hydroxide, methanol and water in step (3) after fine adjustment of sodium concentration and water concentration. The method according to any one of claims 1 to 9, wherein the effluent from step (6) is reused as part of step (5) of the next regeneration process. The continuous manufacturing method of the fatty acid ester from fats and oils which uses the anion exchange resin regenerated with the method as described in any one of Claims 1 thru | or as a heterogeneous solid catalyst. The method according to claim 11, wherein the transesterification and / or adsorption is continuously performed using a reactor filled with an anion exchange resin. The transesterification and / or adsorption is continuously performed using a reactor packed with at least two towers of anion exchange resin connected in series, and the reactor on the uppermost stream side of the at least two towers is packed. When the catalytic activity of the anion exchange resin has disappeared, the anion exchange resin is subjected to a regeneration treatment by the method according to any one of claims 1 to 10 and is disposed on the most downstream side of the remaining reactor. 13. A cycle consisting of continuing a continuous process for the production of fatty acid esters by connecting a reactor filled with an anion exchange resin regenerated by the process, characterized in that the cycle is repeated. the method of. A system for carrying out the method according to any one of claims 11 to 13, wherein the reactor is filled with a cation exchange resin for esterifying free fatty acids contained in the fat and oil raw material, and At least two reactors connected downstream and connected in series with an anion exchange resin used for transesterification and / or adsorption of triglycerides contained in fats and oils, and anion exchange to be regenerated Said system comprising a reactor filled with resin.