CN115652689A - Deep filtering paperboard for bio-pharmaceutical filtration and preparation method thereof - Google Patents
Deep filtering paperboard for bio-pharmaceutical filtration and preparation method thereof Download PDFInfo
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- CN115652689A CN115652689A CN202210785642.1A CN202210785642A CN115652689A CN 115652689 A CN115652689 A CN 115652689A CN 202210785642 A CN202210785642 A CN 202210785642A CN 115652689 A CN115652689 A CN 115652689A
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Abstract
The invention belongs to the field of separation and filtration of biopharmaceuticals, and particularly relates to a deep filtration paperboard for filtering biopharmaceuticals and a preparation method thereof. The invention adopts cellulose fiber as a main body, adds an inorganic filter aid, adopts a mode of adding reinforced resin to enhance the mechanical property of a filter paper board and simultaneously bonds the filter aid to prevent the filter aid from falling off and polluting target liquid, the filter paper board accords with the FDACFR212260 standard, the bacterial endotoxin of the filter board is less than 0.125EU/ml, and the total dissolved matter: the dry content loss is less than 4 percent, the filtration efficiency is more than or equal to 95 percent, the dry strength is more than 120 mN.m, and the wet strength is more than 80 mN.m.
Description
Technical Field
The invention belongs to the technical field of separation and filtration, and particularly relates to a deep filtration paperboard for biopharmaceutical filtration and a preparation method thereof.
Background
The deep filtering paper board is mainly applied to the fields of biotechnology, biological products, blood products, vaccines and filtration, separation and fine filtration of transgenic products. The filter material is used for rough filtering, clarification, fine filtering and microorganism reduction and removal, is particularly suitable for effective and safe separation of colloidal haze, ultrafine particles and microorganisms, and can be used for pre-filtering to realize effective membrane protection.
Depth filtration is a relatively common and effective filtration technique that utilizes a depth filtration media to remove fine particulate contaminants, such as cells, cell debris, bacteria, viruses, etc., in which the contaminants are not only captured at the surface, but also within the internal channels of the media. The depth filter medium has filter holes distributed in the whole thickness of the medium, and the filter holes form bent channels in the medium, so that the depth filter medium has higher dirt holding capacity.
At present, in the bio-pharmaceutical filtration system, a deep filtration paper board is mainly used as pre-filtration to realize effective membrane protection. The deep filtration paper board is composed of cellulose fibers as a framework of the filtration paper board, and inorganic filter aid, binder and other modifiers are added, for example, diatomite and/or perlite are used as the filter aid and cellulose is used as a main filtration matrix in the deep filtration paper board disclosed by the UK patent with the application number of 7907310, so that the provided deep filtration paper board can effectively remove fine particle pollutants such as bacteria, viruses and the like, and a filtrate product meeting the quality requirement is provided. In order to make the filtering paper board have better filtering performance, the united states patent with application number 4007113-4 proposes to use melamine formaldehyde resin as a reinforcing agent of the filtering board, modify the ZETA potential of the paper board, because the melamine formaldehyde resin has free formaldehyde which is harmful to human body, so the british patent with application number 2043734A (B) proposes to use polyamide epichlorohydrin resin as a modifying agent to improve the filtering performance of the filtering board; in order to solve the above problems, the patent proposes a technical scheme of using cellulose ester fibers to replace filter aid diatomite and/or perlite, and although the technical scheme can effectively avoid the problems of medium dissolution and paperboard strength, the price of the cellulose ester fibers is relatively expensive, and the production cost of the paperboard is relatively high. In order to solve the problem of strength of the paper board, german patent No. 10346256B3 proposes that a filter paper board meeting the requirement can be obtained by adding polyolefin fibers with a low melting point into the paper board and sintering the mixture at a high temperature. Chinese patent application No. 110585773A uses modified attapulgite as the filter aid, and although this scheme can make the cardboard after the drying strengthen through the adhesion of attapulgite, along with the cardboard is after the cardboard is soaked to the filtrate in filtering process, the filter cardboard can become soft, and the wet strength of filter plate is not enough, is unfavorable for collecting the filter residue on filter plate surface.
Therefore, it is desirable to provide a deep filtration paper board for bio-pharmaceutical filtration, which can effectively separate fine particles and provide an ideal filtration effect, and the deep filtration paper board has good strength, high strength retention after filtration, low heavy metal ion content, low endotoxin content, good performance and controllable cost compared with the existing production of filtration paper boards.
Disclosure of Invention
The invention relates to a deep filter paper board for bio-pharmaceutical filtration and a preparation method thereof, aiming at solving the problems of easy breakage, easy falling of a filter aid, difficult collection of filter residue after filter plate softening and high production cost of the existing deep filter paper board.
The technical scheme adopted by the invention is as follows: adopting bleached natural plant fiber with 30-60oSR beating degree as main filtering substrate, wherein: the proportion of the cellulose fiber is 30-70%, the proportion of the added inorganic filter aid is 20-30%, the mass proportion of the reinforced resin is 2-10%, the dosage of the wet strength agent is 1-3% of the total mass of the inorganic filter aid solid and the cellulose fiber solid, and a deep filter paper board with the thickness of 1.5-4.5 mm is manufactured by adopting wet papermaking equipment.
The invention also provides a manufacturing method of the deep filtering paperboard for biopharmaceutical filtration, which comprises the following steps:
(1) Mixing and stirring bleached natural plant fibers and water to obtain a cellulose fiber suspension, then feeding the cellulose fiber suspension into a double-disc mill for pulping, increasing the pulping degree of the cellulose fibers to 30-60oSR, and pumping the cellulose fibers to a pulp mixing tank for later use;
(2) Adding an inorganic filter aid into a pulp mixing tank to mix with cellulose fibers, then sequentially adding a wet strength agent and a reinforced resin, and uniformly stirring and mixing, wherein the proportion of the cellulose fibers is 30-70%, the proportion of the inorganic filter aid is 20-30%, the proportion of the reinforced resin is 2-10%, and the using amount of the wet strength agent is 1-3% of the total mass of the inorganic filter aid solids and the cellulose fiber solids;
(3) Removing partial water from the prepared slurry by wet papermaking equipment to obtain a wet paperboard;
(4) Introducing the wet paper board obtained in the step 3 into a hot air drying box for drying, wherein the drying temperature is 130-150 ℃, and the drying is carried out until the dryness of the paper board is 97%;
(5) Adjusting the cutting speed of the horizontal paper cutter, and continuously cutting the dried paper board into a certain size and shape according to the requirement to obtain a dry deep-layer filtering paper board;
(6) And (5) sterilizing and disinfecting the deep filtering paper board obtained in the step (5) to obtain a deep filtering paper board product for bio-pharmaceutical filtration.
The reinforced resin in the step (2) of preparing the deep filtration paper board for bio-pharmaceutical filtration is at least one of melamine formaldehyde resin, urea formaldehyde resin, polyacrylic acid resin, polyacrylamide resin, polyamide resin, polyurethane acrylic resin, styrene-acrylic resin, pure acrylic resin, styrene-butadiene resin or polyethyleneimine resin.
The invention has the advantages that: this deep filtration cardboard not only has better filtering quality, can carry out effectual filtration to tiny granule, and cardboard intensity is high, is difficult for breaking, and the wet stiffness of cardboard is high, can not influence the collection of filter residue. The biological safety is high, the bacterial endotoxin of the filter plate is less than 0.125EU/ml, and the total extract: the dry content loss is less than 4 percent, the filtration efficiency is more than or equal to 95 percent, the dry strength is more than 120 mN.m, and the wet strength is more than 80 mN.m.
Drawings
FIG. 1 scanning electron microscope image of inorganic filter aid and filter paper board
FIG. 2 is a flow chart of a deep filtration paper board process for biopharmaceutical filtration
FIG. 3 comparison of samples before and after filtration
Detailed Description
The invention is described in further detail below with reference to the drawings and examples
Example 1
(1) Mixing and stirring bleached natural plant fibers and water to obtain a cellulose fiber suspension, then feeding the cellulose fiber suspension into a double-disc mill for pulping, beating the pulp degree of the cellulose fibers to 40oSR, and pumping the cellulose fiber suspension into a pulp mixing pool for later use;
(2) Adding an inorganic filter aid into a pulp blending tank, uniformly mixing the inorganic filter aid with cellulose fibers, then sequentially adding a wet strength agent and a reinforced resin, stirring and uniformly mixing, wherein the proportion of the cellulose fibers is 68%, the proportion of the inorganic filter aid is 25%, the proportion of the reinforced resin is 5%, and the using amount of the wet strength agent is 2% of the total mass of the inorganic filter aid solid and the cellulose fiber solid;
(3) Removing partial water from the prepared slurry by wet papermaking equipment to obtain a wet paperboard;
(4) Introducing the wet paper board obtained in the step 3 into a hot air drying oven for drying, wherein the drying temperature is 130 ℃, and the drying is carried out until the dryness of the paper board is 97%;
(5) Adjusting the cutting speed of the horizontal paper cutter, and continuously cutting the dried paper board into a certain size and shape according to the requirement to obtain a dry deep-layer filtering paper board;
(6) And (5) sterilizing and disinfecting the deep filtering paper board obtained in the step (5) to obtain a deep filtering paper board product for bio-pharmaceutical filtration.
Wherein the reinforced resin in the step 2 is at least one of melamine formaldehyde resin, urea formaldehyde resin, polyacrylic resin, polyacrylamide resin, polyamide resin, polyurethane acrylic resin, styrene-acrylic resin, pure acrylic resin, styrene-butadiene resin or polyethyleneimine resin.
Example 2
(1) Mixing and stirring bleached natural plant fibers and water to obtain a cellulose fiber suspension, then feeding the cellulose fiber suspension into a double-disc mill for pulping, beating the cellulose fiber to 50oSR (degree of pulp) and pumping the cellulose fiber to a pulp mixing tank for later use;
(2) Adding an inorganic filter aid into a pulp mixing tank, uniformly mixing the inorganic filter aid with cellulose fibers, then sequentially adding a wet strength agent and a reinforced resin, and uniformly stirring and mixing, wherein the proportion of the cellulose fibers is 65%, the proportion of the inorganic filter aid is 25%, the proportion of the reinforced resin is 8%, and the using amount of the wet strength agent is 1.5% of the total mass of the inorganic filter aid solid and the cellulose fiber solid;
(3) Removing part of water from the prepared slurry by wet papermaking equipment to obtain a wet paperboard;
(4) Introducing the wet paper board obtained in the step 3 into a hot air drying oven for drying, wherein the drying temperature is 120 ℃, and the drying is carried out until the dryness of the paper board is 97%;
(5) Adjusting the cutting speed of a horizontal paper cutter, and continuously cutting the dried paper board into a certain size and shape according to the requirement to obtain a dry deep filtering paper board;
(6) And (5) sterilizing and disinfecting the deep filtering paper board obtained in the step (5) to obtain a deep filtering paper board product for bio-pharmaceutical filtration.
Wherein the reinforced resin in the step 2 is at least one of melamine formaldehyde resin, urea formaldehyde resin, polyacrylic resin, polyacrylamide resin, polyamide resin, polyurethane acrylic resin, styrene-acrylic resin, pure acrylic resin, styrene-butadiene resin or polyethyleneimine resin.
Example 3
(1) Mixing and stirring bleached natural plant fibers and water to obtain a cellulose fiber suspension, then feeding the cellulose fiber suspension into a double-disc mill for pulping, beating the cellulose fiber to 50oSR (degree of pulp) and pumping the cellulose fiber to a pulp mixing tank for later use;
(2) Adding an inorganic filter aid into a pulp blending tank, uniformly mixing the inorganic filter aid with cellulose fibers, then sequentially adding a wet strength agent and a reinforced resin, stirring and uniformly mixing, wherein the proportion of the cellulose fibers is 60%, the proportion of the inorganic filter aid is 30%, the proportion of the reinforced resin is 8%, and the using amount of the wet strength agent is 1.5% of the total mass of the inorganic filter aid solid and the cellulose fiber solid;
(3) Removing part of water from the prepared slurry by wet papermaking equipment to obtain a wet paperboard;
(4) Introducing the wet paper board obtained in the step 3 into a hot air drying box for drying, wherein the drying temperature is 130 ℃, and the drying is carried out until the dryness of the paper board is 97%;
(5) Adjusting the cutting speed of a horizontal paper cutter, and continuously cutting the dried paper board into a certain size and shape according to the requirement to obtain a dry deep filtering paper board;
(6) And (5) sterilizing and disinfecting the deep filtering paper board obtained in the step (5) to obtain a deep filtering paper board product for bio-pharmaceutical filtration.
Wherein the reinforced resin in the step 2 is at least one of melamine formaldehyde resin, urea formaldehyde resin, polyacrylic resin, polyacrylamide resin, polyamide resin, polyurethane acrylic resin, styrene-acrylic resin, pure acrylic resin, styrene-butadiene resin or polyethyleneimine resin.
Example 4
(1) Mixing and stirring bleached natural plant fibers and water to obtain a cellulose fiber suspension, then feeding the cellulose fiber suspension into a double-disc mill for pulping, beating the cellulose fiber to 55oSR (degree of pulp) and pumping the cellulose fiber to a pulp mixing tank for later use;
(2) Adding an inorganic filter aid into a pulp preparation tank, uniformly mixing the inorganic filter aid with cellulose fibers, then sequentially adding a wet strength agent and a reinforced resin, stirring and uniformly mixing, wherein the proportion of the cellulose fibers is 64%, the proportion of the inorganic filter aid is 25%, the proportion of the reinforced resin is 10%, and the consumption of the wet strength agent is 1% of the total mass of the inorganic filter aid solid and the cellulose fiber solid;
(3) Removing partial water from the prepared slurry by wet papermaking equipment to obtain a wet paperboard;
(4) Introducing the wet paper board obtained in the step 3 into a hot air drying oven for drying, wherein the drying temperature is 130 ℃, and the drying is carried out until the dryness of the paper board is 97%;
(5) Adjusting the cutting speed of the horizontal paper cutter, and continuously cutting the dried paper board into a certain size and shape according to the requirement to obtain a dry deep-layer filtering paper board;
(6) And (5) sterilizing and disinfecting the deep filtering paper board obtained in the step (5) to obtain a deep filtering paper board product for bio-pharmaceutical filtration.
Wherein the reinforced resin in the step 2 is at least one of melamine formaldehyde resin, urea formaldehyde resin, polyacrylic resin, polyacrylamide resin, polyamide resin, polyurethane acrylic resin, styrene-acrylic resin, pure acrylic resin, styrene-butadiene resin or polyethyleneimine resin.
Example 5
(1) Mixing and stirring bleached natural plant fibers and water to obtain a cellulose fiber suspension, then feeding the cellulose fiber suspension into a double-disc mill for pulping, beating the cellulose fiber to 60oSR (degree of beating), and pumping the cellulose fiber to a pulp mixing tank for later use;
(2) Adding an inorganic filter aid into a pulp preparation tank, uniformly mixing the inorganic filter aid with cellulose fibers, then sequentially adding a wet strength agent and a reinforced resin, stirring and uniformly mixing, wherein the proportion of the cellulose fibers is 60%, the proportion of the inorganic filter aid is 29%, the proportion of the reinforced resin is 10%, and the consumption of the wet strength agent is 1% of the total mass of the inorganic filter aid solid and the cellulose fiber solid;
(3) Removing partial water from the prepared slurry by wet papermaking equipment to obtain a wet paperboard;
(4) Introducing the wet paper board obtained in the step 3 into a hot air drying oven for drying, wherein the drying temperature is 130 ℃, and the drying is carried out until the dryness of the paper board is 97%;
(5) Adjusting the cutting speed of the horizontal paper cutter, and continuously cutting the dried paper board into a certain size and shape according to the requirement to obtain a dry deep-layer filtering paper board;
(6) And (5) sterilizing and disinfecting the deep filtering paper board obtained in the step (5) to obtain a deep filtering paper board product for bio-pharmaceutical filtration.
Wherein the reinforced resin in the step 2 is at least one of melamine formaldehyde resin, urea formaldehyde resin, polyacrylic resin, polyacrylamide resin, polyamide resin, polyurethane acrylic resin, styrene-acrylic resin, pure acrylic resin, styrene-butadiene resin or polyethyleneimine resin.
TABLE-1 deep filtration paper board test results
As can be seen from Table-1, the deep layer filter plate prepared by the present invention satisfies the biopharmaceutical requirements in terms of strength, filtration flux, bacterial endotoxin, total dissolved matter, and filtration efficiency.
The above embodiments are only used for illustrating the design idea and features of the present invention, and the purpose of the present invention is to enable those skilled in the art to understand the content of the present invention and implement the present invention accordingly, and the protection scope of the present invention is not limited to the above embodiments. Therefore, all changes and modifications that come within the spirit and scope of the invention are desired to be protected by the following claims.
Claims (10)
1. A deep filtration paperboard for biopharmaceutical filtration is characterized in that: the deep filtration paper board for biopharmaceutical filtration meets the FDA CFR212260 standard, wherein the deep filtration paper board for biopharmaceutical filtration comprises bleached natural plant fibers with medium and low beating degree, a wet strength agent, a reinforcing resin and an inorganic filter aid.
2. The depth filtration sheet for biopharmaceutical filtration of claim 1, wherein: the bleached natural plant fiber is bleached sulfate wood pulp, bleached sulfite wood pulp, bleached cotton pulp or a mixture thereof, and the beating degree is 30-60 DEG SR.
3. The depth filtration sheet for biopharmaceutical filtration of claim 1, wherein: the wet strength agent is polyamide epichlorohydrin, the solid content is 15%, DCP is less than 150ppm, and MCPD is less than 300ppm.
4. The depth filtration sheet for biopharmaceutical filtration of claim 1, wherein: the reinforced resin can effectively improve the stiffness of the paperboard, bind the fiber and the inorganic filter aid and prevent the inorganic filter aid from falling off, and is at least one of melamine formaldehyde resin, urea formaldehyde resin, polyacrylic resin, polyacrylamide resin, polyamide resin, polyurethane acrylic resin, styrene-acrylic resin, pure acrylic resin, styrene-butadiene resin or polyethyleneimine resin.
5. The depth filtration sheet for biopharmaceutical filtration of claim 1, wherein: the inorganic filter aid is at least one of activated clay, modified attapulgite, diatomite or perlite.
6. The depth filter sheet for biopharmaceutical filtration of claims 1 and 5, wherein: the average diameter of the inorganic filter aid is less than 15 mu m.
7. A method of manufacturing a depth filter paper sheet for biopharmaceutical filtration as claimed in any of claims 1 to 6, characterized by:
(1) Mixing and stirring bleached natural plant fibers and water to obtain a cellulose fiber suspension, then feeding the cellulose fiber suspension into a double-disc mill for pulping, beating the pulp degree of the cellulose fibers to 30-60 DEG SR, and pumping the cellulose fibers to a pulp mixing tank for later use;
(2) Adding an inorganic filter aid into a pulp preparation tank to be mixed with cellulose fibers, then sequentially adding a wet strength agent and a reinforced resin, and uniformly stirring and mixing, wherein the proportion of the cellulose fibers is 30-70%, the proportion of the inorganic filter aid is 20-30%, the proportion of the reinforced resin is 2-10%, and the using amount of the wet strength agent is 1-3% of the total mass of the inorganic filter aid solid and the cellulose fiber solid;
(3) Removing part of water from the prepared slurry by wet papermaking equipment to obtain a wet paperboard;
(4) Introducing the wet paper board obtained in the step 3 into a hot air drying box for drying, wherein the drying temperature is 130-150 ℃, and the dryness of the paper board is 97%;
(5) Adjusting the cutting speed of the horizontal paper cutter, and continuously cutting the dried paper board into a certain size and shape according to the requirement to obtain a dry deep-layer filtering paper board;
(6) And (5) sterilizing and disinfecting the deep filtering paper board obtained in the step (5) to obtain a deep filtering paper board product for bio-pharmaceutical filtration.
8. The method of claim 7 wherein the deep filtration paper sheet for biopharmaceutical filtration comprises: the wet papermaking equipment is one of an inclined wire paper machine, a fourdrinier wire paper machine, a multi-cylinder paper machine and a wet papermaking machine.
9. The method of claim 7 wherein the deep filtration paper sheet for biopharmaceutical filtration comprises: sterilizing the dried filter paper board by at least one of high-temperature steam sterilization, ultraviolet sterilization or ethylene oxide sterilization.
10. Use of a depth filter paper sheet for biopharmaceutical filtration according to claims 1-6, characterized in that: the deep filtering paper board for filtering the biological pharmacy can effectively remove particles with the particle size of 0.1-10 mu m, the bacterial endotoxin is less than 0.125EU/ml, and the total dissolved substance: the dry content loss is less than 4 percent, the filtration efficiency is more than or equal to 95 percent, the dry strength is more than 120 mN.m, and the wet strength is more than 80mN.
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116180494A (en) * | 2023-02-03 | 2023-05-30 | 杭州科百特过滤器材有限公司 | Deep filtration paperboard and preparation method thereof |
| CN117306312A (en) * | 2023-08-02 | 2023-12-29 | 江苏飞赛过滤科技有限公司 | Deep filtration paperboard and preparation method thereof |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
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| CN110585773A (en) * | 2018-06-13 | 2019-12-20 | 杭州科百特过滤器材有限公司 | Filtering paperboard and preparation method thereof |
| CN114534362A (en) * | 2022-01-29 | 2022-05-27 | 杭州科百特过滤器材有限公司 | Charged deep filtering paperboard and preparation method thereof |
| CN114606793A (en) * | 2022-03-04 | 2022-06-10 | 扬州石化有限责任公司 | Fiber filter paper for disposable medical and sanitary products and manufacturing method thereof |
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2022
- 2022-07-05 CN CN202210785642.1A patent/CN115652689A/en active Pending
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110585773A (en) * | 2018-06-13 | 2019-12-20 | 杭州科百特过滤器材有限公司 | Filtering paperboard and preparation method thereof |
| CN114534362A (en) * | 2022-01-29 | 2022-05-27 | 杭州科百特过滤器材有限公司 | Charged deep filtering paperboard and preparation method thereof |
| CN114606793A (en) * | 2022-03-04 | 2022-06-10 | 扬州石化有限责任公司 | Fiber filter paper for disposable medical and sanitary products and manufacturing method thereof |
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN116180494A (en) * | 2023-02-03 | 2023-05-30 | 杭州科百特过滤器材有限公司 | Deep filtration paperboard and preparation method thereof |
| CN116180494B (en) * | 2023-02-03 | 2024-02-20 | 杭州科百特过滤器材有限公司 | Deep filtration paperboard and preparation method thereof |
| CN117306312A (en) * | 2023-08-02 | 2023-12-29 | 江苏飞赛过滤科技有限公司 | Deep filtration paperboard and preparation method thereof |
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