Method for producing porous cellulose beads

Patent metadata

Field	Value
Publication number	US-9487595-B2
Application number	US-201214001807-A
Country	US
Kind code	B2
Filing date	Mar 6, 2012
Priority date	Mar 8, 2011
Publication date	Nov 8, 2016
Grant date	Nov 8, 2016

Abstract

The objective of the present invention is to provide a convenient method for producing porous cellulose beads having high mechanical strength without using an auxiliary material which is highly toxic and corrosive and without a cumbersome and industrially adverse step. The method for producing porous cellulose beads according to the present invention is characterized in comprising the steps of mixing a cold alkaline aqueous solution and cellulose to prepare a cellulose dispersion and bringing the cellulose dispersion into contact with a coagulating solvent.

First claim

The invention claimed is:

1. A method for producing porous cellulose beads, comprising the steps of:
mixing a cold alkaline aqueous solution and cellulose to prepare a cellulose dispersion; wherein the cellulose concentration in the cellulose dispersion is not less than 1 wt % and not more than 10 wt %, and the temperature of the cold alkaline aqueous solution is not more than 15° C.; and bringing the cellulose dispersion into contact with a coagulating solvent.

2. The method for producing porous cellulose beads according to claim 1 , wherein an alkali concentration in the alkaline aqueous solution is not less than 5 wt % and not more than 15 wt %.

3. The method for producing porous cellulose beads according to claim 1 , wherein a median particle diameter of the cellulose is not less than 10 μm and not more than 500 μm.

4. The method for producing porous cellulose beads according to claim 1 , wherein the coagulating solvent contains an alcohol.

5. The method for producing porous cellulose beads according to claim 1 , wherein the coagulating solvent is acidified.

6. The method for producing porous cellulose beads according to claim 1 , wherein a temperature for preparing and preserving the cellulose dispersion is not less than −20° C. and not more than 10° C.

7. The method for producing porous cellulose beads according to claim 1 , wherein the cellulose dispersion is dispersed in a continuous phase to obtain an emulsion, and then the emulsion is brought into contact with the coagulating solvent.

8. The method for producing porous cellulose beads according to claim 7 , wherein the coagulating solvent has not less than 0.01 times and not more than 1 time as much volume as the emulsion.

9. The method for producing porous cellulose beads according to claim 7 , wherein a value of Pv at the time of preparing the emulsion is not less than 0.1 kW/m 3 , and the value of Pv represents power consumption per volume.

10. The method for producing porous cellulose beads according to claim 1 , wherein a value of Pv at the time of bringing the cellulose dispersion into contact with the coagulating solvent is not less than 0.1 kW/m 3 , and the value of Pv represents power consumption per volume.

11. The method for producing porous cellulose beads according to claim 7 , wherein a time required for adding the coagulating solvent to the emulsion is not more than 150 seconds.

12. The method for producing porous cellulose beads according to claim 1 , wherein the cellulose dispersion is prepared by preparing a preliminary dispersion from water and cellulose and mixing the preliminary dispersion with the alkaline aqueous solution.

13. The method for producing porous cellulose beads according to claim 1 , wherein a stirring operation in at least one step is carried out using a turbine blade.

14. The method for producing porous cellulose beads according to claim 2 , wherein a median particle diameter of the cellulose is not less than 10 μm and not more than 500 μm.

15. The method for producing porous cellulose beads according to claim 2 , wherein the coagulating solvent contains an alcohol.

16. The method for producing porous cellulose beads according to claim 3 , wherein the coagulating solvent contains an alcohol.

17. A method for producing crosslinked porous cellulose beads, comprising the steps of:
mixing a cold alkaline aqueous solution and cellulose to prepare a cellulose dispersion; wherein the cellulose concentration in the cellulose dispersion is not less than 1 wt % and not more than 10 wt %, and the temperature of the cold alkaline aqueous solution is not more than 15° C.; bringing the cellulose dispersion into contact with a coagulating solvent thereby obtaining porous cellulose beads; and the further step of crosslinking the porous cellulose beads.

Assignees

• Kawai Yoshikazu
• Suzuki Yasuyuki
• Morio Kenichiro
• Hirano Masaru
• Kaneka Corp

Inventors

• Kawai Yoshikazu
• Suzuki Yasuyuki
• Morio Kenichiro
• Hirano Masaru

Classifications

• B01J20/28078

  Pore diameter · CPC title

• C08J2201/0546

  the non-solvent being organic · CPC title

• C08L1/02

  Cellulose; Modified cellulose · CPC title

• C08J2301/02

  Cellulose; Modified cellulose · CPC title

• B01J20/3085

  Chemical treatments not covered by groups B01J20/3007 - B01J20/3078 · CPC title