JPS5912720A - Improvement in flow flux of ultrafiltration - Google Patents

Abstract

PURPOSE:To enhance the permeability of an aqueous solution, by a method wherein an aqueous solution containing a high molecular substance such as protein is preliminarily subjected to heat treatment and said high molecular substance is modified and coagulated to prevent the clogging of an ultrafiltration membrane. CONSTITUTION:For example, 48l glutamic acid fermentation liquid is subjected to heat treatment at 60-70 deg.C for 10min to be subjected to ultrafiltration by using a hollow yarn comprising a polysulfone membrane with a ultrafiltration limit M.W. of 6,000. When heat treatment is not carried out, the rapid reduction in a flow flux is recognized directly after ultrafiltration is started but, in the case of heat treatment, the lowering in flow flux is extremely low. As the result, in a filtration time until the amount of a filtered liquid reaches 38l, 5hr is required in the case of untreatment but, in the case of treatment 3hr is required. As apparent from the forgoing, by preliminarily carrying out heat treatment of a solution in the case of ultrafiltration treatment of a microbiological fermentation liquid of amino acid, the flow flux of the solution, that is, the filterability of a membrane can be remarkably enhanced and efficient treatment thereof can be carried out.

Description

[Detailed description of the invention] Microbial fermentation liquid of amino acids etc. is subjected to ultrafiltration as it is,
It is known to remove microorganisms. However, there is a problem in that moss in the fermentation liquor, other than target substances and microorganisms, causes clogging of the microfiltration membrane, resulting in a decrease in the amount of permeated liquid per unit time and unit area of the membrane, that is, the flux.

However, the present inventors have discovered that polymeric substances such as proteins can be heated to
Focusing on this property of denaturation and aggregation, we discovered that the above problems could be solved by ultrafiltrating the fermentation solution and then heating the solution in advance. completed. That is, as mentioned above, heating can denature and aggregate high molecular substances such as proteins, prevent clogging of the ultrafiltration membrane, and increase the 7-ranox, that is, permeation performance of the solution. It is.

The detailed conditions for the heat treatment vary depending on the type of liquid to be treated, but are usually 50 to +000 liters, and several seconds to several tens of minutes. In addition, whether the ultrafiltration after heating may be carried out while it is heated, or after cooling is determined depending on the performance of the ultrafiltration membrane and the properties of the target substance. Should be).

Incidentally, ultrafiltration itself is a well-known technique as described above, and the liquid to be treated that has undergone the pretreatment according to the present invention may be subjected to such a known ultrafiltration treatment.

The ultrafiltration membrane used in the present invention 1 may be any ordinary semipermeable membrane, and is not particularly limited. Possible materials include boria, polyacrylonitrile, polysulfone, and cellulose acetate. The type of membrane is tube] 1×I', l
There are vague, spiral, hollow fiber shapes, etc., but this is also 1.
¥) I don't care. The filtration limit molecular weight of the membrane is 5.000 to 1, taking into consideration the lI permeation rate, removal rate of proteins, etc.
A value of the order of 00,000 is convenient.

Hereinafter, the present invention will be explained in more detail with reference to Examples.

Example 1 48 tons of glutamic acid fermentation liquid was heated for 60 to 70 minutes for 10 minutes, and ultra-seeding was performed.

As a control, 48 tons of the same fermentation liquid was heated without heating using a sulfone membrane with a filtration limit molecular weight of 6.000, the membrane structure was a hollow fiber type, and the membrane area was 0.2y++'.
The applied pressure was 1-2 kW/cnf, and the filtration temperature was 35-45r. In both cases, the amount of liquid was 38
Filtration was carried out until tl. That is, in terms of concentration ratio, both are 4.8 times.

The results are shown in Table It.

Table 1 (Present invention) (Ri・j Teru) 81
0.00 81
0.0074 0.23
57 0. +572
0.52 46 0.4
566 1.15 42
+, 1561 2.00
3 B 2.005
6 2.30 35
2.4554 2.45
31 3.4550
3.00 28
4.4527 5.00 As clearly shown in Table It, in the case without heat treatment (control), a rapid decrease in flux was observed immediately after the start of filtration, but in the case of heat treatment (invention) 1
Here, the decrease in flux is extremely small. As a result, in the case of no treatment, it took 5 hours as the appropriate time for v.1, but in the case of heat treatment, it was completed in 3 hours, about 60% of the time.

By heating the solution, flanox,
In other words, it will be understood that membrane filtration performance is significantly improved compared to conventional methods, and efficient processing can be achieved.

Patent Applicant Ajinomoto Co., Ltd. Procedural Amendment @ (Method) 1981 101128 Director General of the Patent Office Kazuto Wakasugi 1, Indication of Case 1982 Patent Application No. 121/150 2, Invention title limitation'/ Relationship between Membrane Filtration 'A' A-bundle number method 3 and the person making the amendment 1'1 Special W [Applicant () Tokyo Chuo 1st Kyobashi-cho "No. 15-8 (Delivery 1)" 1933 10J]2F')El)
7. Contents of the amendment Column of the name of the invention for the specification / drawing i1 1981 101] L ) 1 1. Matter ('1 indication Showa 57 (T:i letter '1 condyles No. 121450 2, Title of the invention: Excessive Flux Improvement Method 3, ?Li Positive Speller $1!F Which Relationship Patent Applicant: 11 Places: Kyobashi-chogl, Chuo-ku, Tokyo 5M August 5,
Number of excuses increased by amendment None 7, m1il
Contents (1) The scope of the special ill request will be amended as shown in the attached sheet. .

(2) [Ended] written on page 5, line 2 for Akira 1llll. ] Next, enter the following information. .

[Example 2 Lysine but vinegar solution 36e was heat-treated at 90-100"C for 5 minutes and ultrafiltered. As a control, the same light vinegar solution 36e was heated as it was without heating, 11" Ultrafiltration was performed using one filter.

The ultrafiltration strip A'1 is as shown below and J3. In other words,
The membrane is a polyacrylonitrile membrane with a molecular width of 13,
000, the membrane structure is Toshira, and the concentration 1
In other words, filtration was carried out until the liquid volume reached 3.6℃. ．In 8 hours・
there were. Average iIa.

Displayed in speed 4 times f, each 7'13℃, -'m'll
, 58 l,,'m'l l. ” Attachment 2, #: s8' to Kt'! If the desired range of amino acids is exceeded, the solution should be heated to 50 to 100" in advance.
A method for improving ultraviolet flux, which is characterized by denaturing and aggregating H white, etc. to prevent clogging of the membrane during filtration.

l

Claims (1)

[Claims] Ultrafiltration flux is characterized in that an aqueous solution containing proteins, etc. is passed through a v-filter, and the solution is heated in advance to denature and aggregate proteins, etc., thereby preventing clogging of the membrane during filtration. Improved method.