JPS6296100A - Production of high quality sugar solution - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a method for producing a colorless and transparent high-quality sugar solution, and in particular, a method for producing a sugar solution using a powdered basic anion exchange resin. It relates to a purification method.

[Summary of the invention]

The present invention decolorizes and/or desalts and purifies the sugar solution to be treated using a granular basic anion exchange resin, and then makes it contact react with a powdered basic anion exchange resin. The aim is to produce a colorless and transparent high-quality sugar solution.

[Conventional technology]

In one row, 7 Yoshiaki Granyu Sentang? Yokaku ￥) 7 equivalent to night
In order to produce Yashitang products, the ultimate goal of refining sugar technology is to reduce as much as possible the colorless pigments contained in the sugar solution and make it colorless and transparent. It goes without saying that this has great industrial value. Therefore, various studies have been made on methods for purifying sugar solutions, one of which is the application of ion exchange resins.

By the way, in the conventional field of sugar solution purification, most of the applied technologies for ion exchange resins are granular ion exchange resins, and the development of technology for powdered ion exchange resins has just begun. Also, regarding the application method of ion exchange resin, activated carbon.

It has been thought that a system configuration in which the final finishing process is performed after various refining processes using bone char, flocculants, etc. is rational. However, with such a system configuration, no matter what kind of adsorbent is used after the ion exchange resin step, a portion of the dye that is difficult to decolorize remains, making it impossible to obtain a colorless and transparent sugar solution.

Therefore, in order to produce high-quality liquid sugar as mentioned above, it is necessary to use a method in which crystallized sugar is precipitated from the final purified fine liquor, separated and dried, and then dissolved. I couldn't.

[Problems to be solved by the invention] However, this method of producing liquid sugar by precipitating crystallized sugar from the winter refining process and redissolving it again requires a large number of steps. There are many problems in terms of productivity, yield, etc.

Therefore, an object of the present invention is to make it possible to remove the above-mentioned dye that is difficult to bleach, and to make it possible to produce a crystalline granulated sugar solution and a colorless and transparent high-quality sugar solution that does not fade.

[Means for solving problems]

The present inventors have taken the lead in the research and development of powdered ion exchange resins, and have already proposed the application of powdered basic anion exchange resins to the field of sugar liquid purification in Japanese Patent Application Laid-Open No. 145100/1983. did. As we continue to conduct practical tests on powdered ion exchange resins, we have discovered that we can effectively combine this powdered ion exchange resin with granular ion exchange resins, and that under certain conditions tJ! The present invention was achieved based on the finding that the above-mentioned difficult-to-decolorize dye, which was considered impossible to remove by any conventional method, can be removed by contact reaction with a liquid.

That is, the first invention of the present invention consists of a decolorizing and/or desalting purification step using a granular basic anion exchange resin, and a post-treatment step in which the powdery basic anion exchange resin is subjected to a catalytic reaction. , and a second invention includes a decoloring and/or desalting purification step using a granular basic anion exchange resin;
It consists of a post-treatment step in which a powdered basic anion exchange resin is subjected to a contact reaction, and is characterized in that the powdered basic anion exchange resin whose capacity has been reduced due to the post-treatment step is regenerated and used repeatedly. It is something.

Furthermore, the powdered basic anion exchange resin whose capacity has been reduced in the post-treatment process can be sufficiently used as a cleaning agent in the pre-treatment process of the decolorization or desalting purification process using the granular basic anion exchange resin. The third invention of the present invention includes a pretreatment step using a powdered basic anion exchange resin as a cleaning agent, and a decolorization and/or decolorization process using a granular basic anion exchange resin.
Alternatively, it consists of a desalting purification step and a post-treatment step in which a powdered basic anion exchange resin is subjected to a contact reaction, and the powdered basic anion exchange resin used in the above pre-treatment step is the same as the powder used in the above-mentioned post-treatment step. A fourth aspect of the present invention is a pretreatment step using a powdered basic anion exchange resin as a cleaning agent; It consists of a decolorizing and/or desalting purification process using a granular basic anion exchange resin, and a post-treatment process in which the powdered basic anion exchange resin is subjected to a catalytic reaction,
The powdered basic anion exchange resin used in the above pre-treatment step is the recovered powdered basic anion exchange resin used in the above-mentioned post-treatment step. This method is characterized in that the basic anion exchange resin is regenerated and used again in a post-treatment step.

The simplest system of the present invention, as shown in FIG.
The sugar solution is first treated with decolorization/desalting purification step 1 using a granular basic anion exchange resin, and then subjected to a post-treatment step 2 using a powdered basic anion exchange resin, which is the method of the present invention. This corresponds to the first invention. jlIn order to remove the decolorizing pigment and produce a clear sugar solution, it is necessary to undergo a purification process using a granular ion exchange resin, followed by a contact reaction with a powdered ion exchange resin. It is difficult to produce the desired high-quality sugar solution with extensive cultivation.

The powdered basic anion exchange resin used in the present invention has a quaternary ammonium group in the matrix such as a copolymer of styrene and divinylbenzene or a copolymer of acrylic and divinylbenzene.

In the case of strongly basic anion exchange resins having exchange groups such as alkanol groups and tertiary amine groups, other resins may be used.

Although it has a greater purification effect than fats, it can also be used with weakly basic anion exchange resins. In addition to the OH form, there are various salt forms of the ion, and the OH form and Cl form of strong salt-resistant anion exchange resins are particularly effective.

The particle size of the powdered basic anion exchange resin is 2
It is preferably 50 μm or less, more preferably 1
00 μm or less. When the particle size exceeds 250 μm, the ability to adsorb dyes that are difficult to decolorize decreases, and it becomes difficult to remove adsorbed substances, mainly dye components. On the other hand, if the particle size of the powdered basic anion exchange resin is 5 μm or less, especially 1.5 μm or less where there is a high risk of leakage, it will be difficult to filter and separate the ion exchange resin in the sugar solution to be treated. There is a risk that it may be mixed in.

Methods for producing the powdered basic anion exchange 10 resin include a method of pulverizing a granular ion exchange resin and a method of industrial synthesis, but pulverization is preferable for -C. Further, as the pulverization method, there are air flow pulverization method, freeze pulverization method, a mechanical pulverization method, etc., and it is particularly preferable to use the air flow pulverization method or the freeze pulverization method.

The above-mentioned air flow crushing method is a method in which the particulate anion exchange resin, which is the raw material, is self-pulverized into fine particles by vibrations caused by high-frequency pressure fluctuations caused by high-speed swirling of air.
It has the characteristic that the time required to powder it to 50 μm or less is extremely short (about several seconds). According to this pulverization method, the temperature rise during pulverization is 40°C or less, so there is no deterioration of the resin due to heat, and powdered ion exchange has excellent desorption properties of pigment components and has a large regeneration effect. Resin is obtained.

In addition, in the freeze-pulverization method, a granular anion exchange resin is brought into direct contact with, for example, liquid nitrogen to be cooled to -100'C or less, and then the cooled anion exchange resin is immediately pulverized using a hammer mill or the like. It is something. In this case as well, thermal deterioration does not occur, and a powdered anion exchange resin with fine particle size and relatively uniform particle size can be obtained.

On the other hand, in the mechanical pulverization method using a ball mill or hammer mill, it is difficult to make the particle size of the pulverized product uniform, and when using the obtained powdered anion exchange resin, it is necessary to use a sieve etc. to It is necessary to select and use things. Furthermore, in the above-mentioned mechanical pulverization method, the time required for pulverization is long and the temperature rise is large, so there is a possibility that the decolorizing performance of the powdered anion exchange resin may be reduced. Generally, anion exchange resins have relatively low heat resistance. For example, the maximum operating temperature of OH thick-type strong base anion exchange resins with quaternary ammonium groups as ion exchange groups is said to be 60°C; Exceeding this temperature rapidly causes thermal decomposition of the ion exchange groups. The details of the adsorption mechanism of the dye component by the anion exchange resin are unknown, but it is thought that the polarity of the surface of the anion exchange resin particles is largely involved, so it is undesirable to apply heat during pulverization.

The powdered basic anion exchange resin used in the present invention may be prepared by pulverizing a used granular basic anion exchange resin whose capacity has decreased due to repeated use. For example, the granular basic anion exchange resin that has been repeatedly used in the decolorization/desalting purification step 1 and whose purification ability has decreased can be pulverized and used as the powdered basic anion exchange resin in the post-treatment step 2.

Further, the purpose can be sufficiently achieved by using the powdered basic anion exchange resin in an amount of 0.5% or less based on the sugar solution to be treated.

*J! according to the present invention! ? & Refined Fl sugar solution applied to Nostem is purified a from which suspended components are removed through a pretreatment process such as carbonation saturation method, phosphoric acid purification method, or microfiltration method.
It is better to use I-tang liquid. This means that the three turbid components are
This is because it becomes a filtration-inhibiting component and becomes a major hindrance when regenerating and repeatedly reusing powdered salt-free anion exchange resin over many cycles. However, like Nostem shown in Figure 1,
When there is no need to regenerate and repeatedly use the powdered basic anion exchange resin, it is not necessary to use a clear sugar solution, and the powdered basic anion exchange resin adsorbs and removes these suspended components to generate tRa. Rather, it acts effectively to obtain sugar solution.

The reaction conditions for the powdered basic anion exchange resin and the sugar solution to be treated may be either a mixing method or a pre-coating method, and there is no significant difference in the purification effect whether the reaction temperature is room temperature or 80°C. When using, use diatomaceous earth or various fibrous i
It is preferable to use these filter aids in combination, since the use of these filter aids in combination facilitates the separate filtration operation between the sugar solution to be treated and the ion exchange resin.

By the way, the present inventors have already disclosed a method for regenerating powdered ion exchange resin in Japanese Patent Application No. 59-165520, but especially when used in combination with the present invention, the effect will be tremendous. .

That is, as shown in FIG. 2, if the powdered basic anion exchange resin whose capacity has decreased in the post-treatment step 2 is regenerated in the regeneration step 3 and repeatedly used in the above-mentioned post-treatment step 2, the running It is extremely advantageous in terms of cost and disposal of waste pellets. It was also found that regeneration is easy in this case. Generally, when regenerating granular ion exchange resin, a relatively high concentration of acid (8 liquids) with a concentration of about 1 to 10% is used.
Although the pH at the time of regeneration is set to a value considerably lower than 1, in the present invention, the dye that is difficult to decolorize was adsorbed. Contact with a ~100 times dilute acid solution (preferably at a temperature of 40°C or higher) for a short time (about 5 minutes) and stir, or do the same? 8 X! It is sufficient to flow 1 ffl into the resin layer. The acid solution used here has a pH of 1.82 or less (e.g. pH 2 to pH Hl) and an acid concentration of 0.1.
About 0.5% can be used. Diluted like this? 8
The fact that it can also be used as a liquid means that only a small amount of regenerating agent (eg, acid) can be used, which has immeasurable economic benefits. Of course, the method for regenerating the powdered basic anion exchange resin is not limited to this.
For example, it is also effective to use a regenerating agent for a granular basic anion exchange resin as it is as a regenerating agent for the powdered basic anion exchange resin.

In addition, in the above-mentioned regeneration of the powdered basic anion exchange resin, when using the powdered ion exchange resin prepared from the used granular ion exchange resin, when regenerating only with the M solution, the reason is not clear. It was found that the purification ability of the new powdered ion exchange resin was significantly lower than that of the new powdered ion exchange resin. As a countermeasure to this problem, the problem could be solved by treating with an acid solution for 7 nights and then reacting with NaOH or NaOH-containing N-containing NaCl ascites solution.

On the other hand, powdered basic anion exchange resins have a greater purification ability than granular basic anion exchange resins, and the amount of equilibrium adsorbed dye per unit resin is close to that of the latter. Therefore, it is not necessarily advisable to proceed to a disposal or regeneration process just by adsorbing a small amount of a dye that is difficult to decolorize (although this alone has sufficient industrial value). According to experiments conducted by the present inventors, in the system shown in FIG. 1 or 2, the powdered basic anion exchange resin used in post-treatment step 2 is treated with a granular basic anion exchange resin. It was found that even if it was reused as it was for the previous high color value sugar solution, its refining ability was almost the same as that of a new product.

Therefore, as shown in Figure 3, the sugar solution to be treated is first used in post-treatment step 2, and the powdered basic anion exchange resin with reduced capacity is recovered and treated as a cleaning agent in pre-treatment step 4. However, a system may be adopted in which the product is then subjected to a decolorizing/desalting purification step 1 using a granular basic anion exchange resin and a post-treatment step 2 using a powdery basic anion exchange resin. This system corresponds to the third aspect of the present invention.

Furthermore, as shown in FIG. 4, the powdered basic anion exchange resin whose capacity has decreased after being used in the pre-treatment step 4 is regenerated in the regeneration step 5 and used repeatedly in the post-treatment step 2. It is also possible to set it as a system. In this case, the regeneration method is similar to regeneration step 3 in the system shown in Figure 2 above, regeneration using a dilute acid solution at 40°C or higher, or regeneration using an acid solution/night and an alkaline solution. good. Having such a system
This makes it possible to effectively utilize the ion exchange resin without waste.

By the way, in each of the above-mentioned systems, the decolorization/desalting purification process 1 using a granular salt viscous anion exchange resin is a decolorization/desalting purification process using an OH type strong salt method anion exchange resin (so-called MAK method). It is most effective when it is structured as follows. This MAK method involves sequentially passing a mixture of a strongly basic anion exchange resin and a strongly acidic cation exchange resin through a mixed column, a strongly basic anion exchange resin column, and a weakly acidic cation exchange resin column. It has become clear that by employing the M A K method, it is possible to produce a colorless and transparent sugar solution that is comparable to the highest quality liquid sugar made by dissolving granulated sugar.

Further, by adopting the present invention, a secondary effect that was not initially expected was also produced. That is, according to the present invention, the combination of granular basic anion exchange resin and 15] terminal basic anion exchange resin enables the bone char/granular charcoal (activated carbon) process, which has been the main part of the conventional sugar refining process. It has become clear that even if these steps are omitted, fine liquor that is comparable to the conventional method can be produced. This means that by adopting the present invention, the refining capacity will be greatly reduced. It shows that it has reached the upper limit in terms of A, and it is the source of low quality! This shows that even in the case of low-quality (high color value) sugar solution with increased tetrasaccharide or sugar washing yield, high-quality sugar solution can be stably produced.

[Effect]

There are few examples of using powdered ion-exchange resins to purify sugar solutions, and the decolorization mechanism of ion-exchange resins themselves has not been elucidated, so we will analyze why such a large difference in decolorization appears using the above-mentioned system. Although it is difficult to do so, we make the following assumptions.

In other words, if a powdered ion exchange resin is used before the granular ion exchange resin process, polar dyes that have a strong affinity with the ion exchange resin will react preferentially, and dyes that are difficult to decolorize, mainly dyes that are presumed to have weak polarity, will react. Dye remains. Granular basic anion exchange resins have a lower adsorption capacity than powdered ion exchange resins, and it is considered difficult to adsorb and remove weakly polar and decolorizable dyes. On the other hand, when using a granular basic anion exchange resin as a pretreatment, most of the pigments contained in the treated sugar solution are weakly polar and difficult to decolorize pigments, but the adsorption capacity (particularly physical adsorption) It is believed that only powdered ion-exchange resins with a high capacity can effectively adsorb and remove this difficult-to-decolorize dye. (Even in the case of granular basic anion exchange resins, it is sometimes possible to obtain a colorless and transparent sugar solution with no dye leakage using a new resin, especially in the first distillate. This phenomenon and the conditions of the present invention (It is presumed that this is a complete failure.) [Example] The present invention will be described below based on specific experimental examples. It goes without saying that these experimental examples do not limit the present invention.

Experimental example 1゜Sugar factory final refined sugar solution (granular ion exchange resin process output =
MAK process effluent) was heated to 70℃1 using the following various decolorizing agents.
After stirring and contacting the reaction for 30 minutes, the sugar solution was filtered using a 0.8 μm membrane filter, and the absorption characteristics in the visible region were measured. In addition, the amount of decolorizing agent used is 0.2% (dry Th) in the case of powdered strongly basic ion exchange resin.
Others were set at 0.5% (dry matter). For comparison, a sugar solution prepared by dissolving crystalline sugar (granulated 1-tang) was also investigated. The results are shown in Table 1.

As is clear from the test results in Table 1, a high quality sugar solution corresponding to the quality of the crystalline tang solution was obtained only with the powdered strongly basic ion exchange resin. After contacting and reacting powdered ion exchange resin with the liquid sugar (liquid charcoal process effluent) supplied to the MAK process, a comparative study was also carried out on the sugar liquid purified in the MAK process, but a sugar liquid of the target quality could not be obtained. .

A similar test was also conducted on a weakly basic anion exchange resin that had been air-pulverized. As a result, by increasing the amount of resin used (approximately 1.5 times), a high quality W liquid almost equivalent to that obtained using a strongly basic ion exchange resin was obtained. Such properties are unique to powdered ion exchange resins, which are not found in granular weakly basic anion exchange resins.

Experimental Example 2゜ Raw sugar was treated according to the following refining process,
A refined sugar solution was obtained.

(Al raw tetrasaccharide - Washed sugar - Carbonated saturation method - Recovery Powdered ion exchange resin - Granular basic anion exchange resin (MIIK method process) - Powdered ion exchange resin - Sugar sugar solution ATB + Raw sugar - Washed ↓ J TO Carbonation filling method - Recovered powdered ion exchange resin - Granular charcoal - MAK method - Powdered ion exchange resin - Refined sugar solution b tel raw sugar - Washed sugar Monocarbonate filling method Single granular charcoal - MAKl removal = <n Made!N 'a c The quality of purified $1!a by each purification process is shown in Table 2.

Of the above processes, the process (C) is the conventional method, and the process (al and mountain) is the method of the present invention. In addition, the powdered ion-exchange resin used in this experiment was used for 300 cycles to improve sugar refining overnight, and the discarded resin was regenerated with warm hydrochloric acid, followed by warm saline containing sodium hydroxide, and then averaged by air-flow pulverization. The particle size was adjusted to 27 μm.

Approximately half of iIt super-aiding agent (silica 600H) is added to this resin and mixed to form a precoat a with a height of 2 cmFt.
Current was passed at ν, 0.2.

Furthermore, the recovered powdered ion exchange resin is made by passing through the MAK process effluent 1000 times (per dry powdered ion exchange resin).
The idea is to reuse it by cutting it into carbonated process effluent as it is.

Table 2 Purification 1J! Although Liquid A was simplified by omitting the granular charcoal process, it was found that it was comparable to the conventional refined sugar solution. Refined sugar solution is a high quality (colorless, 1 light) sugar solution, and is a granule I! It was revealed that this was a high-purity sugar solution equivalent to the lysis solution.

Experimental Example 3 Similarly to Experimental Example 2 above, raw sugar was treated according to the following purification process to obtain a refined sugar solution.

+di raw sugar - sugar washing - carbonate cell filling method (magnesium method) -
Recovered powdered ion exchange resin - Chlorine type strongly basic anion exchange resin - Powdered ion exchange resin - Purified sugar raw materials - Washed sugar monocarbonate cell filling method (magnesium method) -
Granular charcoal (or bone char) - chlorine type strongly basic anion exchange resin - refined sugar solution e Among the above processes, the tel process is the conventional method, and the (di process is the method of the present invention).

The powdered ion exchange resin was used in the same manner as in Experimental Example 2. In this experiment, a new granular basic anion exchange resin (trade name: Amparite IRA-401) was pulverized by a pneumatic pulverization method to obtain an average particle size of 23 μm.

After passing through the recovered powder ion exchange (approximately 1000 times (per dry resin) in the negative resin process), 0°5% HC/aqueous solution (70°C)
The resin! A regeneration operation was carried out by adding 40 times the amount of (dry product) and stirring for 5 minutes to desorb the adsorbed dye.

The test results after the IO cycle are shown in Table 3. It has also been found that when the magnesium method is employed, a high-quality sugar solution can be obtained by using powdered weakly acidic cation exchange resin in combination to remove residual magnesium.

Table 3 Experimental Example 4 The following regeneration operations were carried out on the recovered powdered ion exchange resin used in the (al) process of Experimental Example 2 above.
The purification ability after repeated use was compared.

Regeneration method I: Add 50 m + 2 of water per 1 g of powdered ion exchange resin whose capacity has decreased due to use in the (al process) of Experimental Example 2, add 35% H (l) to bring the pH to below 1, and then heat at 70°C. Stir for 5 minutes while heating to
The powdered ion exchange resin and the regenerated liquid were separated using the following method. After thorough washing and adjusting the pH to 7 with washing/'rI solution, the amount of desorbed dye was determined.

Regeneration method 2: The pH was adjusted to 1 to 2 using the same method as above.

Regeneration method 3: The pH was adjusted to 2 to 3 using the same method as above.

Regeneration method 4: After implementing regeneration method 2, 1 g of powdered ion exchange resin was brought into contact with 3 ml of a 1% aqueous sodium hydroxide solution, thoroughly washed with water, and both waste liquids were combined and tested in the same manner.

Regeneration method 5: In regeneration method 4, 10% sodium chloride water i8 containing 2% sodium hydroxide is used instead of the 1% sodium hydroxide aqueous solution. (The test was conducted in the same manner as in Regeneration Method 4 except that 8 mg of I was heated to 70°C.

The results are shown in Table 4.

(The following is a blank space) Table 4 In Table 4, the amount of dye desorption is a comparison value with respect to the amount of dye desorbed by regeneration method 1 as a reference (desorption rate of 80% with respect to adsorption amount).

〔Effect of the invention〕

As is clear from the above description, in the present invention,
With a simple system in which the Ti liquid to be treated is first treated with a granular basic anion exchange resin and then post-treated with a powdered basic anion exchange resin, high-quality sugar can be produced without going through complicated processes such as activated carbon. liquid can be produced.

In addition, the powdered basic anion exchange resin used in the above system is prepared by pulverizing used granular basic anion exchange resin, and is regenerated with a low concentration acid solution, making effective use of the resin. This is extremely suitable for achieving this goal.

Furthermore, it adsorbed dyes that are difficult to decolorize, reducing its ability.)
It is also possible to use the terminal basic anion exchange resin as it is in the pretreatment step of the granular basic anion exchange resin to achieve even more effective utilization. By using such a system, crystal I! (granulated sugar) It becomes possible to produce an extremely high quality sugar solution product equivalent to the solution.

[Brief explanation of drawings]

FIG. 1 is a flowchart showing the process order of the sugar liquid purification system corresponding to the first invention of the present invention, and FIG. 2 is a flowchart showing the process sequence of the sugar liquid purification system corresponding to the second invention. Figure 3 shows tI! corresponding to the third invention.
Flowchart showing the process sequence of the liquid purification system, No. 4
The figure is a flowchart showing the process sequence of the sugar liquid purification system according to the fourth invention. Patent Applicant Igechu IJS Co., Ltd. Agent Patent Attorney Kodo Koike Sakae Tamura

Claims (12)

[Claims] (1) A method for producing a high-quality sugar solution, which comprises a purification step of decolorizing and/or desalting using a granular basic anion exchange resin, and a post-treatment step of catalytically reacting the powdered basic anion exchange resin. (2) The powdered basic anion exchange resin used in the post-processing process is a powdered basic anion prepared by pulverizing a granular basic anion exchange resin whose purification ability has decreased after being used for sugar solution purification. 2. The method for producing a high-quality sugar solution according to claim 1, wherein the method is an exchange resin. (3) It consists of a decolorization and/or desalting purification process using a granular basic anion exchange resin and a post-treatment process in which the powdered basic anion-exchange resin is subjected to a contact reaction, and the powder has a reduced ability due to the post-treatment process. A method for producing a high-quality sugar solution, characterized by regenerating and reusing a basic anion exchange resin. (4) Claim 3, characterized in that the powdered basic anion exchange resin whose capacity has decreased due to the post-treatment step is regenerated by contact reaction with an acid solution at a temperature of 40° C. or higher and a pH of 2 or lower. The method for producing the high quality sugar solution described. (5) The powdered basic anion exchange resin whose capacity has decreased due to the post-treatment process is regenerated by contact reaction with an acid solution at a temperature of 40°C or more and pH 2 or less, and then contact reaction with an alkaline solution. A method for producing a high-quality sugar solution according to claim 3. (6) The method for producing a high-quality sugar solution according to claim 5, wherein the alkaline solution is a sodium hydroxide solution or a sodium chloride solution containing sodium hydroxide. (7) A pretreatment step using a powdered basic anion exchange resin as a cleaning agent, a decolorization and/or desalting purification step using a granular basic anion exchange resin, and a catalytic reaction of the powdered basic anion exchange resin. and a post-treatment step, wherein the powdered basic anion exchange resin used in the pretreatment step is recovered from the powdered basic anion exchange resin used in the post-treatment step. A method for producing high-quality sugar solution. (8) The powdered basic anion exchange resin used in the post-treatment process is a powdered basic anion prepared by pulverizing a granular basic anion exchange resin whose purification ability has decreased after being used for sugar solution purification. 8. The method for producing a high-quality sugar solution according to claim 7, wherein the method is an exchange resin. (9) A pretreatment step using a powdered basic anion exchange resin as a cleaning agent, a decolorization and/or desalting purification step using a granular basic anion exchange resin, and a catalytic reaction of the powdered basic anion exchange resin. The powdered basic anion exchange resin used in the above pretreatment step is the recovered powdered basic anion exchange resin used in the above posttreatment step, and the powdered basic anion exchange resin used in the above pretreatment step is A method for producing a high-quality sugar solution, characterized by regenerating a powdered basic anion exchange resin whose capacity has decreased in a process and using it again in a post-treatment process. (10) Claim 9, characterized in that the powdered basic anion exchange resin whose capacity has decreased due to the pretreatment step is regenerated by contact reaction with an acid solution at a temperature of 40° C. or higher and a pH of 2 or lower. The method for producing the high quality sugar solution described. (11) The powdered basic anion exchange resin whose capacity has decreased due to the pretreatment step is regenerated by contact reaction with an acid solution at a temperature of 40°C or more and pH 2 or less, and then contact reaction with an alkaline solution. A method for producing a high quality sugar solution according to claim 9. (12) The method for producing a high-quality sugar solution according to claim 11, wherein the alkaline solution is a sodium hydroxide solution or a sodium chloride solution containing sodium hydroxide.