Search

CN-121976416-A - Preparation method of hydrophobic depth filtration paperboard, hydrophobic depth filtration paperboard and filter press

CN121976416ACN 121976416 ACN121976416 ACN 121976416ACN-121976416-A

Abstract

A preparation method of a hydrophobic deep filtration paperboard is characterized in that natural fibers are subjected to hydrophobic modification, so that uniform hydrophobic performance is given to the deep filtration paperboard, the interaction between the surface of the paperboard and a filter cake layer can be reduced, and the filter cake is convenient to peel. The hydrophobic natural fiber can be uniformly dispersed in water without additional treatment, so that the hydrophobic fiber does not need to be subjected to pre-hydrophilic treatment in the preparation of the paperboard, and the preparation method is simple in process and low in cost. The invention uses low-melting point fiber as the binder, which can strengthen the surface fiber of the deep-layer filter paper board, when the filter cake is scraped off, the surface fiber of the deep-layer filter paper board can not fall off, and has extremely high wet strength and bending strength, compared with the traditional deep-layer filter paper board, the filter cake can be scraped off, and the filter cake can not be damaged due to bending and twisting in a wet state. The filter press provided by the invention has the advantages of low cost, convenience in use and higher practical value.

Inventors

  • ZHANG QUPING
  • JIA QIJUN

Assignees

  • 艾里奥斯生物科技(上海)有限公司

Dates

Publication Date
20260505
Application Date
20260317

Claims (20)

  1. 1. A method for preparing a hydrophobic depth filtration paperboard, comprising the steps of: Pretreating natural fibers to obtain natural wet fibers; Grafting a silane coupling agent on the surface of the natural wet fiber to obtain a natural fiber dispersion liquid; Adding hydrophobic silane into the natural fiber dispersion liquid, and grafting to obtain hydrophobic natural fibers; dispersing the hydrophobic natural fibers in water to obtain hydrophobic natural slurry; blending the hydrophobic natural pulp, the fine natural fiber pulp and the low-melting-point fibers, and adding a wet strength agent to obtain paperboard pulp; And dehydrating, drying and shaping the paperboard slurry to obtain the hydrophobic deep filtration paperboard.
  2. 2. The method of making a hydrophobic depth filtration paperboard of claim 1, wherein the pre-treating the natural fibers comprises: Pulping the natural fibers to obtain natural fiber slurry; and dehydrating the natural fiber slurry to obtain the natural wet fibers.
  3. 3. The method of making hydrophobic depth filtration paper board of claim 2 wherein the natural fiber slurry has a freeness of 40 oSR or less and the natural wet fiber has a water content of 70wt.%.
  4. 4. A method of making a hydrophobic depth filtration paperboard according to claim 3, wherein the grafting of a silane coupling agent onto the surface of the natural wet fibers comprises: Adding ammonia water and the natural wet fibers into the anhydrous alcohol solution, stirring and heating; and (3) dropwise adding a silane coupling agent into the solution, stirring, and reacting to obtain the natural fiber dispersion liquid.
  5. 5. The method for preparing the hydrophobic depth filtration paperboard according to claim 4, wherein the mass ratio of the anhydrous alcohol, the ammonia water and the natural wet fiber is as follows: 84-89% of absolute alcohol; 3-8% of ammonia water; 8% of natural wet fiber.
  6. 6. The method for preparing the hydrophobic depth filtration paper board according to claim 5, wherein the mass ratio of the silane coupling agent to the natural wet fiber is: 5-7 parts of silane coupling agent; 3-5 parts of natural wet fibers.
  7. 7. The method of producing a hydrophobic depth filtration paper board according to claim 6, wherein the silane coupling agent is a R 2 Si(OR 1 ) 3 type silane coupling agent.
  8. 8. The method of making a hydrophobic depth filtration paperboard of claim 7, wherein the adding hydrophobic silane to the natural fiber dispersion and grafting results in hydrophobic natural fibers comprising: Slowly dripping the hydrophobic silane into the natural fiber dispersion liquid, stirring and reacting; carrying out vacuum dehydration on the natural fiber dispersion liquid after the reaction is finished; and repeatedly cleaning the natural fiber dispersion liquid with deionized water and absolute ethyl alcohol in sequence until the natural fiber dispersion liquid is neutral, and carrying out vacuum dehydration again to obtain the hydrophobic natural fiber.
  9. 9. The method of making a hydrophobic depth filtration paper board according to claim 8, wherein the hydrophobic silane is XSi (OR 3 ) 3 type hydrophobic silane).
  10. 10. The method of making a hydrophobic depth filtration paperboard of claim 9, wherein the hydrophobic silane is present in a ratio to the natural wet fibers of: NFs:75-87; 13-25 parts of hydrophobic silane.
  11. 11. The method for preparing the hydrophobic depth filtration paperboard according to claim 10, wherein the mass ratio of the hydrophobic natural fiber slurry, the fine natural fiber slurry, the low melting point fiber and the wet strength agent is as follows: 51.3 to 70.5 portions of hydrophobic natural fiber slurry; 12.8 to 32.1 portions of fine natural fiber slurry; 12.8 to 25.6 portions of low-melting-point fibers; 3-4 parts of wet strength agent.
  12. 12. The method for preparing the hydrophobic depth filtration paper board according to claim 11, wherein the hydrophobic natural fiber slurry, the fine natural fiber slurry and the low melting point fiber are blended, and a wet strength agent and a filter aid are added to obtain the paper board slurry.
  13. 13. The method of producing a hydrophobic depth filtration paper board according to claim 12, wherein the fine natural fiber pulp is obtained by beating natural fibers, and the fine natural fiber pulp has a beating degree of 80oSR or more.
  14. 14. The method of making a hydrophobic depth filtration paperboard of claim 13, wherein the low melting point fibers are synthetic fibers having a melting point of 140 ℃ or less.
  15. 15. A hydrophobic depth filtration paperboard prepared by the method of any one of claims 1-14.
  16. 16. The hydrophobic depth filtration sheet of claim 15 wherein the hydrophobic depth filtration sheet has a liquid inlet contact angle of 95-148 °.
  17. 17. The hydrophobic depth filtration paper board of claim 15 wherein the flow rate of the hydrophobic depth filtration paper board is 164-272 (L/(m -2 *min -1 ).
  18. 18. The hydrophobic depth filtration paperboard of claim 15 having a cake yield of 85-98%.
  19. 19. The hydrophobic depth filtration paperboard of claim 15 having a wet strength of 12-20bar.
  20. 20. The hydrophobic depth filtration paperboard of claim 15 having a flexural rigidity of 8261-10379mN.

Description

Preparation method of hydrophobic depth filtration paperboard, hydrophobic depth filtration paperboard and filter press Technical Field The invention belongs to the technical field of biological pharmaceutical processes, and particularly relates to a preparation method of a hydrophobic depth filtration paperboard, the hydrophobic depth filtration paperboard and a filter press. Background The plasma product is a plasma protein component or blood cell component product prepared by the separation, purification or recombinant DNA technology of healthy human plasma or specific immune human plasma. The current blood products in China mainly comprise plasma protein products purified from human plasma. It is known that human blood plasma contains about 200 or more protein components with unique biological functions, and the modern industry can separate and purify 20 or more blood plasma protein components. At present, in the purification preparation of plasma protein products, the most important filtering technology is a filter pressing technology, the filter pressing technology adopts a filter press for filtering, the filter press comprises a filter plate, the filter plate comprises a deep-layer filtering paper board, and feed liquid enters the filter press from the liquid inlet surface of the filter plate and is filtered through the deep-layer filtering paper board. The filter-press technology is a combination of filter cake filtration and deep filtration technology, wherein the filter cake filtration mainly depends on screening, liquid can pass through small holes of a filter medium during filtration, particles larger than the small holes are trapped and stacked by the medium to form a filter cake, so that the filter effect is achieved, and the deep filtration mainly depends on tortuous pore structures in the filter medium to adsorb and intercept particles smaller than the pores of the filter medium. When the deep filtration medium filters insoluble matters such as protein in blood, the protein can be continuously accumulated on the feeding surface of the filter plate to form a filter cake, and the filter cake and the deep filtration paper board act together to further purify the protein. Because the protein in blood is generally hydrophilic protein, the filter cake formed on the liquid inlet surface of the traditional deep filtration paper board is easy to combine and adhere with the surface of the deep filtration paper board, when the filter cake is scraped from the deep filtration paper board, the condition that the filter cake is partially adhered on the deep filtration paper board and is not easy to peel off can occur, and when the filter cake is scraped, the fiber on the liquid inlet surface of the filter board is easy to be scraped into the filter cake, so that the problems of lower yield of the filter cake and increased impurities are caused. In order to solve the problems, the Chinese patent No. 115646069A (deep filtration paper board, preparation method and blood filtration method) mainly controls the roughness of the paper board liquid inlet surface to realize the convenience of filter cake stripping, and the mechanical properties are mainly provided by controlling the cellulose fiber diameter and filter aid. The Chinese patent CN113584879A (a micro-nano hydrophobic wood fiber and a preparation method thereof) provides a preparation method of the hydrophobic wood fiber, a sol-gel method is adopted to generate even nano-sized silica particles on the surface of the wood fiber, and then the silica particles react with fluorosilane under an alkaline condition, so that the micro-nano hydrophobic wood fiber is obtained. The modification method has strong hydrophobicity after final drying, but in the process of preparing the paper board, the dried hydrophobic fibers are difficult to disperse secondarily in aqueous solution, the hydrophobic fibers can be uniformly dispersed in water only by carrying out pre-hydrophilic treatment, the pre-hydrophilic treatment is generally soaking treatment by using surfactant, the problem that the surfactant remains in the paper board exists, and the risk exists in the detection of the elution and precipitation of the paper board. In addition, in the process of forming the paper board sheet, the requirements on conditions such as vacuum degree control, drying temperature and the like are high. In the prior art, resin fibers, natural fibers, a wet strength agent and a filter aid are adopted, the aim of hydrophobicity of the paper board is achieved by means of hydrophobicity of the resin fibers, but the hydrophobicity of the resin fibers is not particularly strong, the water contact angle of the resin fibers cannot reach more than 130 degrees, the resin fibers can be uniformly dispersed in an aqueous solution after the pre-hydrophilic treatment is needed in the pulp mixing step, the similar problems exist, and in the paper board sheet forming process, the requirements on condit