JPH0513639B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention is a treatment method in which a sugar solution containing two or more types of saccharides is passed through a separation tower filled with a strongly acidic cation exchange resin, and then elution water is passed through to chromatographically separate each saccharide in the sugar solution. It is related to. Conventionally, strong acids have been used to separate each sugar from a sugar solution containing at least two or more types of sugars, such as a mixed sugar solution of glucose and fructose, a mixed sugar solution of glucose and maltose, or a mixed sugar solution of fructooligosaccharide and other sugars. Chromatographic separation using cation exchange resins has been carried out. The chromatographic separation involves passing a certain amount of the sugar solution through a separation column filled with a strongly acidic cation exchange resin such as a calcium type or sodium type cation exchange resin, and then passing a certain amount of eluent water. Then, each sugar is separated due to the difference in distribution of each sugar in the solution to the ion exchange resin, and each separated liquid flows out with a chromatographic concentration distribution. For example, when a certain amount of sugar solution containing glucose and fructose is passed through a separation column filled with a calcium-type strongly acidic cation exchange resin, and then a certain amount of eluate water is passed through a separation column, there will be a concentration peak in the effluent. Although their bases overlap somewhat, the glucose concentration peak occurs first, followed by the fructose concentration peak. Note that if the sugar solution contains a small amount of oligosaccharides, the oligosaccharide concentration peak occurs before the glucose concentration peak. Therefore, by repeating the operation of passing the sugar solution through, then passing eluate water through, and collecting the effluent separately for each fraction, it is possible to obtain a relatively high-purity fructose solution from a mixed sugar solution of glucose and fructose. can. Traditionally, the chromatographic separation methods described above have been used to separate not only glucose and fructose, but also various sugars such as maltose and fructooligosaccharides, as described above, on an industrial scale. During the treatment, the strongly acidic cation exchange resin packed in the separation column undergoes irreversible swelling as it is used, causing various problems. To explain this in detail below, in the chromatographic separation using the strongly acidic cation exchange resin mentioned above, if the particle size of the cation exchange resin used is the same, the one with a low degree of crosslinking, in other words, the divinylbenzene content In general, the separation performance for each sugar is better when the number of sugars is smaller. However, as the divinylbenzene content decreases, the physical strength of the cation exchange resin decreases in proportion to it, so it is not possible to use a resin with a very low divinylbenzene content, and conventionally, a resin with a divinylbenzene content of 4-7% Among them, one type of strongly acidic cation exchange resin that is most suitable for the sugar solution to be treated in terms of separation performance and physical strength is selected, and this resin is packed into a separation column for use. When chromatographic separation is continued using such a separation column, the strong acid cation exchange resin layer, which exists slightly below the upper layer of the strongly acidic cation exchange resin layer, that is, the surface that first comes into contact with the sugar solution and eluate water, is removed. The ion exchange resin undergoes irreversible swelling as its water content increases and its volume increases, and in extreme cases, the resin particles swell into a gelatinous state, resulting in a very large pressure loss in the upper layer, and the sugar solution This impedes the uniform flow of eluent water and causes one-sided flow of the liquid, which significantly reduces the separation performance of the separation column. Irreversible swelling of the strongly acidic cation exchange resin occurs due to the cross-linked portions that constitute the three-dimensional structure of the resin particles.
This is caused by repeated contraction and swelling of the ion exchange resin due to alternate contact between the sugar solution and the eluate water, or by heavy metals acting as catalysts. Possible causes include oxidation caused by dissolved oxygen or microbial oxidation. Regardless of the cause, if the strongly acidic cation exchange resin packed in the separation column causes irreversible swelling, the above-mentioned troubles will occur, so stop the chromatographic separation operation at an appropriate time and prevent irreversible swelling. It is necessary to take out the cation exchange resin and replace it with a new one. However, in general, the amount of cation exchange resin packed into a separation tower for chromatographic separation treatment is large, and even if only a portion of the amount is replaced, the economic burden is large, and furthermore, The operation is complicated because the separation operation must be interrupted and only a portion of the packed bed is replaced. Note that if a strongly acidic cation exchange resin filled in the separation column is used that has a considerably high divinylbenzene content, for example 10% or more, the physical strength will increase, thereby avoiding the various troubles caused by irreversible swelling mentioned above. be able to. However, as the divinylbenzene content increases, the separation performance for sugars decreases, so currently, as mentioned above, the divinylbenzene content is 7%.
The above strongly acidic cation exchange resins are not used. The irreversible swelling of the strongly acidic cation exchange resin described above is most noticeable when the sugar solution to be separated is a sugar solution containing glucose and fructose, and is particularly problematic in the fructose separation process. The present invention solves these drawbacks in chromatographic separation processing, and provides chromatographic separation processing that can effectively avoid irreversible swelling of the strongly acidic cation exchange resin packed in the separation column without reducing the separation performance of sugars. The purpose of this method is to pass a saccharide containing two or more types of saccharides through a separation column filled with a strongly acidic cation exchange resin, and then pass eluent water through the separation tower to obtain a solution in the saccharide solution. In chromatographically separating each saccharide, a separation column is used that is filled with at least two or more types of strongly acidic cation exchange resins with different divinylbenzene contents in stages from the one with the highest divinylbenzene content to the one with the lowest divinylbenzene content. , relates to a method for chromatographic separation of a sugar solution, characterized in that the sugar solution is passed through the strongly acidic cation exchange resin side containing a large amount of divinylbenzene, and then eluent water is passed through. The present invention will be explained in detail below. The present invention is based on the fact that in conventional separation columns, the strongly acidic cation exchange resin that causes irreversible swelling is noticeable in the upper layer, that is, the area slightly below the surface where the sugar solution and eluate water first come into contact, and that only this portion This is based on the knowledge that the separation performance of the entire packed bed hardly deteriorates even if a strongly acidic cation exchange resin with a high divinylbenze content (hereinafter referred to as DVB content) is filled.
Using a separation tower filled with at least two or more types of strongly acidic cation exchange resins with different contents in stages from the one with the highest DVB content to the one with the lowest DVB content, we can produce a strong acidic cation exchange resin with a high DVB content. This is where the sugar solution and elution water flow in from the side. FIG. 1 is an explanatory diagram of an example of an embodiment of the separation column used in the present invention.
Three types of strongly acidic cation exchange resins with different contents are filled in a multi-layered structure. That is, the upper part of the separation column 1 is filled with high DVB content resin A, the lower part is filled with medium DVB content resin B, and the lower part is filled with low DVB content resin C. Note that 2 is an inflow pipe for the sugar solution and eluate water, 3 is a collection pipe for the separated liquid, and 4 is a bottom plate. Generally, the height of the resin layer in a separation column for chromatographic separation is 5 m to 10 m, but for example, if the total resin layer height in Figure 1 is 6 m, high DVB content resin A
1 m of strong acidic cation exchange resin with 10% DVB content as resin B, 1 m of strong acidic cation exchange resin with 6% DVB content as KDVB content resin B, and 1 m of strong acidic cation exchange resin with 6% DVB content as resin B.
As the DVB content resin C, a strongly acidic cation exchange resin having a DVB content of 5% is filled stepwise to 4 m from the one with the highest DVB content to the one with the lowest DVB content, as viewed from the inlet pipe 2 side. In addition, inflow pipe 2
Needless to say, in an upflow type separation tower in which the liquid collecting pipe 3 is located at the bottom and the liquid collecting pipe 3 is located at the top, the arrangement of the resins A, B, and C described above is completely reversed. In addition, as mentioned above, the area where irreversible swelling occurs is noticeable in the layer slightly below the surface that is first in contact with the sugar solution and eluent water, so the resin layer height of high DVB content resin A and medium DVB content resin B was set too high. There's no need to. On the other hand, if the resin bed height of the high DVB content resin A is made too high, the sugar separation performance of the entire separation column will deteriorate, which is not preferable. FIG. 2 is an explanatory diagram showing another embodiment of the separation column used in the present invention, in which a separation column consisting of a single column is used.
Two types of strongly acidic cation exchange resins with different DVB contents are packed separately. That is, a support plate 5 is attached above the middle part of the separation column 1,
The upper part of the support plate 5 is filled with high DVB content resin A, and the lower part is filled with low DVB content resin C. In Fig. 2, 2 is an inflow pipe, 3 is a liquid collection pipe, and the liquid collection pipe 3' on the high DVB content resin A side and the low
The inflow pipe 2' on the DVB content resin C side is connected through a communication pipe 6. For example, in Figure 2, the high DVB content resin A is a strongly acidic cation exchange resin with a DVB content of 8%, and the low DVB content resin C is a strongly acidic cation exchange resin with a DVB content of 5%. Fill it up to 4m. Figure 3 shows two separation towers, each of which is filled with two types of strongly acidic cation exchange resins with different DVB contents.
DVB content resin A is filled, and the latter separation column 1 is filled with low DVB content resin C. In addition, the liquid collection pipe 3' of the separation column 1 in the former stage and the separation column 1 in the latter stage
Needless to say, the inflow pipes 2' are connected through the communication pipe 6. Furthermore, in Fig. 4, there are two separation towers, and the two separation towers are filled with three types of strongly acidic cation exchange resins having different DVB contents.
High DVB content resin A is applied to the upper part of the support plate 5 of the former separation column 1, medium DVB content resin B is applied to the lower part of the support plate 5 of the former separation column 1, and low DVB content is applied to the latter separation column 1. They are each filled with content resin C. Note that the corresponding liquid collection pipe 3' and inflow pipe 2' are connected through a communication pipe 6 as shown in FIG.
It is similar to FIG. In the present invention, as shown in Figures 1 to 4, at least two or more types of strongly acidic cation exchange resins with different DVB contents are filled in stages from the one with the highest DVB content to the one with the lowest DVB content. However, as shown in FIGS. 2 and 3, the object of the present invention can be fully achieved by using two types of cation exchange resins having different DVB contents. Of course, three or more types of cation exchange resins can be used as shown in FIGS. 1 and 4, and how many types of cation exchange resins to use may be determined depending on the situation. The high DVB content resin A has a DVB content of 8.
It is preferable to use one with a content of ~10%, and the height of the resin layer is preferably at least 0.5 m or more. In addition, when filling a separation column with strongly acidic cation exchange resins with different DVB contents, it is possible to have a multilayer structure as shown in Figure 1, but if the separation column is packed in a multilayer structure, each resin must be taken out separately. This is somewhat inconvenient, and for example, when backwashing, the various resins may mix.
As shown in FIGS. 3 and 4, it is desirable to fill the resins with different DVB contents in a spaced manner. In addition, the liquid collection mechanism of a separation tower usually has a large number of liquid collection pipes 3, 3' arranged in parallel to the cross section of the separation tower 1, as shown in FIG. A header tube 7 is used which communicates with one end of the header tube 3', but as shown in FIG. , 3' are preferably provided. As shown in FIG. 7, the bottom plate 4 or support plate 5 is composed of a corrugated plate 8 and a flat plate 9.
By providing a water collection part 10 consisting of a liquid collection hole or a liquid collection slit at the bottom of 3', the separated liquid flows along the surface of the corrugated plate 8 in the direction of the arrow line, thereby causing the separation liquid to flow between the bottom plate 4 or the support plate 5 and each other. Since there is no dead space where liquid accumulates between the liquid collecting pipes 3 and 3', spoilage of sugar can be effectively prevented and separated liquids with sharp separation curves can be obtained. In the present invention, when a sugar solution containing glucose and fructose, for example, is subjected to chromatographic separation using the separation column as described above, it is carried out as follows. In other words, 0.1 to 0.2/% of the total resin amount by conventional method.
of the sugar solution flows in from the inflow pipe 2, and then 0.15
Chromatographic separation is performed by injecting ~0.25% elution water and passing through each resin layer, and the effluent is allowed to flow out from the liquid collection tube 3. The effluent is collected by fraction and separated into glucose solution and fructose solution. Then, the operations of inflowing the sugar solution and eluate water and collecting the effluent by fraction are repeated. In the present invention, a strongly acidic cation exchange resin with a high DVB content is used in the part that first comes into contact with the sugar solution or eluate water, so that the strong acid cation exchange resin in that part, which occurs in conventional separation columns, is The ion exchange resin does not cause irreversible swelling, and in areas where irreversible swelling does not occur, a
Since a strongly acidic cation exchange resin with a low DVB content is used, the separation performance of the separation column as a whole hardly deteriorates, and chromatographic separation can be carried out stably for a long period of time. Note that when the DVB content of the resins used is the same, the smaller the particle size, the higher the sugar separation performance. By reducing the particle size, it is possible to compensate for the decrease in separation performance of the resin part with a high DVB content, and in this way, the decrease in the separation performance of the entire separation column can be compensated for. This can be more completely prevented. Examples will be described below to make the effects of the present invention more clear. Reference example Strongly acidic cation exchange resins with DVB content of 5%, 6%, 8%, and 10% are respectively made into calcium form.
Fill a column with 20 ml of each of the four types of resin, and add 50 ml of glucose 52% to the column at 60°C.
43% fructose, Bx45 sugar solution, and 50 ml of elution water are passed alternately, and if one cycle is one pass of sugar solution and elution water, this is performed for 2000 cycles,
After measuring the moisture content of each resin,
The results are as shown in Table 1.

[Table] From the above results, it can be seen that the rate of increase in water content, in other words, the irreversible swelling rate becomes smaller as the DVB content increases. Example A set of four jacketed acrylic columns with an inner diameter of 47.5 mm and a length of 1.7 m was used, (1)
Two columns were filled with strongly acidic cation exchange resin with a DVB content of 10%, and the remaining two columns were filled with
(2) One column filled with strongly acidic cation exchange resin with 6% DVB content and arranged in series in descending order of DVB content. (2) Strongly acidic cation exchange resin with 10% DVB content per column. (3) All four columns filled with resin and filled with strongly acidic cation exchange resin with a DVB content of 6% in the remaining three columns, and four columns arranged in series in descending order of DVB content. DVB
Filled with 6% strong acidic cation exchange resin,
4 columns arranged in series, (4) all 4 columns
A separation column consisting of four sets of multi-stage separation columns filled with a strongly acidic cation exchange resin with a DVB content of 10% and arranged in series was constructed, and the following chromatographic separation process was performed on each of these four sets of separation columns. Summer. The resin layer height per column for all columns is
The length was 1.5m, and all calcium type resins were used. In other words, the liquid to be processed is 52% glucose and fructose.
Using a Bx45 sugar solution containing 43%, the sugar solution was reduced to 3.85
After passing through the solution, 6.42 hours of elution water was passed through, the first effluent 4.3 was discarded, and the subsequent effluent was fractionated into A fraction 2.46, B fraction 2.46, C fraction 1.82, D fraction 1.61, and E fraction 1.93. The A fraction was collected as a glucose solution and the D fraction was collected as a fructose solution outside the system, and then the B fraction (2.46), the sugar solution (1.71), the C fraction (1.82), the E fraction (1.93), and the eluate water (2.35) were collected in that order. The conventional circulation method involves passing the solution through the system, separating it again into A, B, C, D, and E fractions, and collecting the A and D fractions in the same way as a glucose solution and a fructose solution. Chromatographic separation treatment using a liquid was performed. 7 of this chromatographic separation process,
The average analytical values of the fructose solution of the D fraction in the 8th, 9th, and 10th cycles were as shown in Table 2.

[Table] As shown in Table 2, separation columns using all strongly acidic cation exchange resins with a DVB content of 10% have low fructose content and poor separation performance.
In (1) and (2) of the present invention, the DVB content is 10
% of strong acidic cation exchange resin is used, but since it has a strong acidic cation exchange resin with a DVB content of 6% at the bottom, the separation performance does not deteriorate that much, and especially In the present invention (2), the separation performance is almost the same as that in the case (3) in which a strongly acidic cation exchange resin with a DVB content of 6% is used in all columns.

[Brief explanation of the drawing]

Figures 1 to 7 all show embodiments of the present invention, with Figure 1 being an explanatory diagram of a separation column used in the present invention, and Figures 2, 3, and 4 all showing embodiments of the present invention. FIG. 3 is an explanatory diagram of another embodiment of the separation column used in the present invention. Further, FIG. 5 is an explanatory plan view showing the liquid collection mechanism section of the separation tower, FIG. 6 is an explanatory cutaway side view of the same section, and furthermore, FIG. 7 is an enlarged longitudinal sectional view of the liquid collection mechanism. DESCRIPTION OF SYMBOLS 1... Separation column, 2... Inflow pipe, 3... Liquid collection pipe, 4... Bottom plate, 5... Support plate, 6... Communication pipe, 7... Header pipe,
8... Corrugated plate, 9... Flat plate, 10... Water collection part, A... High
DVB content resin, B...medium DVB content resin, C...
Low DVB content resin, t…Top.

Claims (1)

[Claims] 1. A sugar solution containing two or more types of saccharides is passed through a separation tower filled with a strongly acidic cation exchange resin, and each saccharide in the sugar solution is then passed through eluent water. For chromatographic separation, a separation tower is used that is filled with at least two types of strongly acidic cation exchange resins with different divinylbenzene contents in stages from the one with the highest divinylbenzene content to the one with the lowest divinylbenzene content. 1. A method for chromatographic separation of a sugar solution, characterized in that the sugar solution is passed through the strongly acidic cation exchange resin side, which has a large amount, and then eluent water is passed through. 2. The method for chromatographic separation of a sugar solution according to claim 1, which uses a separation column filled with strongly acidic cation exchange resins having different divinylbenzene contents. 3. The method for chromatographic separation of a sugar solution according to claim 1 or 2, wherein the sugar solution is a sugar solution containing at least glucose and fructose.