Porous carbons

• US 20040024074A1
• Filed: 05/29/2003
• Published: 02/05/2004
• Est. Priority Date: 08/09/2000
• Status: Abandoned Application

• Current Assignee: MAST Carbon International Ltd.
• Original Assignee: MAST Carbon International Ltd.
• Inventors: Kozynchenko, Oleksandr Prokopovych, Blackburn, Andrew John, Tennison, Stephen Robert, Strelko, Volodymyr Vasyljovych
• Application Number:
  US10/344,248
• Publication Number:
  US 20040024074A1
• Time in Patent Office: Days
• US Class Current: 521/99
• CPC Class Codes: C01B 32/00 Carbon; Compounds thereof C01B21/00, C01B23/00 take precedence; percarbonates C01B15/10; carbon black C09C1/48
• CPC Class Codes: C01B 32/318 characterised by the starting materials
• CPC Class Codes: C04B 2235/77 Density
• CPC Class Codes: C04B 35/52 based on carbon, e.g. graphite
• CPC Class Codes: C04B 35/524 obtained from polymer precursors, e.g. glass-like carbon material
• CPC Class Codes: C04B 38/0022 obtained by a chemical conversion or reaction other than those relating to the setting or hardening of cement-like material or to the formation of a sol or a gel, e.g. by carbonising or pyrolysing preformed cellular materials based on polymers, organo-metallic or organo-silicon precursors
• CPC Class Codes: C04B 38/0054 the pores being microsized or nanosized
• CPC Class Codes: C04B 38/0064 Multimodal pore size distribution
• CPC Class Codes: C04B 38/009 Porous or hollow ceramic granular materials, e.g. microballoons C04B18/027, C04B20/002 take precedence
• CPC Class Codes: C04B 38/062 the burned-out substance being formed in situ, e.g. by polymerisation of a prepolymer composition containing ceramic powder
• CPC Class Codes: Y10T 428/24273 including aperture
• CPC Class Codes: Y10T 428/2982 Particulate matter [e.g., sphere, flake, etc.]

Abstract

A porous resin which can be carbonised to a mesoporous carbon can be made by cross-linking a phenolformaldehyde pre-polymer in the presence of a pore former;, preferably ethylene glycol in an amount of at least 120 parts by weigh of ethylene glycol per 100 parts resin and carbonising the resin formed. The resin can be formed in situ by condensing a phenol with/without modifying agents with cross-linking agent by pouring the partially cross-linked resin into hot oil mesoporous resin beads are obtained which can be carbonised to mesoporous carbon beads.

Claims

1. A method for forming porous resin structure which method comprises condensing a nucleophilic component with an electrophilic cross linking agent in the presence of a pore former.

2. A method for forming porous resin structure as claimed in claim 1 in which the nucleophilic component is a phenolic compound or a phenol condensation pre-polymer.

3. A method as claimed in claim 2 in which the phenol condensation pre-polymer is a Novolac resin, as herein defined.

4. A method as claimed in claim 2 or 3 in which the phenolic compound is a phenol, hydroquinone, or resorcinol.

5. A method as claimed in any one of the preceding claims in which the pore former is a diol, a diol-ether, a cyclic ester, a substituted cyclic or linear amide or an aminoalcohol.

6. A method as claimed in claim 5 in which the pore former is ethylene glycol, 1,4 butylene glycol, diethylene glycol, triethylene glycol, gamma-butyrolactone, propylene carbonate, dimethylformamide, N-methyl-2-pyrrolidinone or monoethanolamine.

7. A method as claimed in any one of the preceding claims in which there is at least 120 parts pore former per 100 parts of the polymer components by weight.

8. A method as claimed in any one of the preceding claims which is carried out in solution and the pore former is also the solvent.

9. A method as claimed in claim 8 in which the solvent comprises a mixture of a diol with water.

10. A method as claimed in claim 8 in which the solvent comprises a binary or tertary or more complex mixture of pore formers from claim 6 and water.

11. A method as claimed in any one of claims 1 to 10 in which the cross-linking agent is formaldehyde, furfural or hexamethylenetetramine.

12. A method as claimed in any one of the preceding claims in which the pore former is removed by washing after the formation of the resin.

13. A method as claimed in any one of claims 1 to 12 in which a solution, obtained by dissolving a Novolac pre-polymer together with one or more of modifying reagents, cross-linking agents and catalysts, in the pore former as a solvent, and heating the solution to bring about a cross-linking reaction, resulting in a solid resin.

14. A method as claimed in claim 13 in which a solid porous polycondensation resin is produced by heating the with an acid or basic catalyst.

15. A method as claimed in any one of claims 13 or 14 in which the modifying reagent is urea, aniline or other aromatic amine or melamine or other heteroaromatic amine.

16. A method as claimed in claim 13 to 15 in which the porous resin is produced in blocks and then comminuted and carbonised to obtain a particulate carbon.

22. A method as claimed in any one of the preceding claims in which a dispersion of a heteroatom, is incorporated in the porous resin structure.

23. A method as claimed in claim 22 in which the heteroatom is a metal and is incorporated in the porous resin structure by adding a solution of a salt to the pore former prior to cross-linking the resin

24. A method as claimed in claim 22 in which the heteroatom is a non metal and is incorporated in the porous resin structure by adding an organic precursor containing the heteroatom to the pore former prior to cross-linking the resin

25. A method as claimed in claim 22 in which the heteroatom is a non metal and is incorporated in the porous resin structure by adding an inorganic precursor containing the heteroatom to the pore former prior to cross-linking the resin.

26. A method as claimed in any one of claims 1 to 25 in which the porous resin is carbonised to produce a porous carbon.

27. A method as claimed in claim 26 in which carbonisation is performed at temperatures up to 800°

C. and in a flow of inert gas.

28. A method as claimed in claim 27 in which an inert gas is carbon dioxide, or nitrogen, or argon.

29. A method as claimed in claims 26 to 28 in which the resulting granulated carbon consists of particles of irregular form with the size ranging from 2 microns to 2000 microns.

30. A method as claimed in claim 26 to 28 in which the resulting granulated carbon consists of spherical particles with the size ranging from 2 to 1600 microns.

31. A method as claimed in claim 29 or 30 in which the porous carbon has a mean pore size of between 2 and 50 nm (mesopores) or bigger than that (macropores) and there are present micropores with a mean pore size between 0.6 and 2 nm.

32. A method as claimed in any one of claims 26 to 31 in which the porous carbon is activated by heating in carbon dioxide or steam.

33. A method as claimed in any one of claims 26 to 31 in which porous carbon is activated by heating in air above 400°

C.

34. A porous carbon made by the method of any one of claims 26 to 33.

35. Mesoporous phenolic resins beads made by the method of any one of claims 1 to 24.

17. A method as claimed in any one of 1 to 11 in which the reaction solution is heated until a limited degree of cross-linking has occurred to produce a partially cross-linked liquid resin solution.

18. A method as claimed in claim 17 in which the mixture is heated until a limited degree of cross linking has occurred and the partially cross linked liquid is poured into an immiscible liquid containing a dispersing agent and the mixture stirred until the partially cross linked polymer is formed into beads which are removed from the immiscible liquid to form resin beads.

19. A method as claimed in claim 17 or 18 in which the immiscible liquid is an oil.

20. A method as claimed in claim 18 or 19 in which a water soluble, but hardly soluble in the dispersing oil pore former is used for meso/macroporous resin production.

21. A method as claimed in claim 18, 19 or 20 in which the particle size of the mesoporous resin beads formed is between 5 and 2000 microns.

36. Phenolic resins beads with diameters from 2 microns to 2000 microns with a pore size of mean diameter from 5 nm to 50 nm (mesopores) and above 50 nm (macropores).

37. Porous carbon spheres of diameter 2 to 1600 microns with a pore size of mean diameter from 2 nm to 50 nm (mesopores) and above 50 nm (macropores).

39. Porous carbon spheres as claimed in claim 37 or 38 in which the BET surface area is from 250 to 800 m²/g.

38. Porous carbon spheres of diameter 2 to 1600 microns in which there is a mixture of pore sizes comprising mesopores of mean diameter from 2 nm to 50 m or above 50 nm (macropores) and micropores of mean diameter 0.6 to 2 nm.