WO2007114849A2

WO2007114849A2 - Activated carbon from carbohydrate

Info

Publication number: WO2007114849A2
Application number: PCT/US2006/060294
Authority: WO
Inventors: Edward R. Buiel
Original assignee: Meadwestvaco Corporation
Priority date: 2005-11-04
Filing date: 2006-10-27
Publication date: 2007-10-11
Also published as: WO2007114849A3

Abstract

Material and means for rendering a high surface area to an activated carbon substrate by creating internal pore structures and high adsorptive capacity from a carbohydrate precursor are disclosed. Activated carbons are used in multiple liquid and gas adsorptive applications, and are particularly advantageous as electrodes for energy storage devices.

Description

IN THE UNITED STATES PATENT AND TRADEMARK OFFICE

ACTIVATED CARBON FROM CARBOHYDRATE

This non-provisional application relies on the filing date of provisional U.S. Application Serial No. 60/733,690, filed on November 4, 2005, having been filed within twelve (12) months thereof, which is incorporated herein by reference, and priority thereto is claimed under 35 USC § 1.19(e).

FIELD OF INVENTION

[0001] This invention relates to a material and means for rendering a substrate to a high surface area by creating significant internal pore structure. More particularly, this invention relates to methods for producing activated carbon having internal pore structure and high adsorptive activity from carbohydrate precursor. The invention activated carbons are used in multiple liquid and gas adsorptive applications, and are particularly advantageously used in electrodes for energy storage devices.

BACKGROUND OF THE INVENTION

[0002] Activated carbon is a microcrystalline, nongraphitic form of carbon that has been processed to increase internal porosity. Characterized by a large specific surface area, typically in the range of 500-2500 m²/g, activated carbons have industrial uses in the purification of liquids and gases by the adsorption of gases and vapors from gases and of dissolved or dispersed substances from liquids such as for water purification. Due to their extended surface area and microporous structure, they find applications as filters, membranes, sorbents and catalyst supports for materials in both gas and liquid phases. Additionally, activated carbon has extensively used as electrode material for energy storage devices.

[0003] The properties and suitability of activated carbons toward specific applications is dictated in large measure by the precise character of the porosity of the carbon. In particular, the size, shape and the distribution in size of pores heavily influence the characteristics of the porous material and its suitability for a given application. Pore structures can assume a multitude of shapes and configurations each varying in shape, depth and width. Pores having characteristic dimensions (diameter or width) less than 2 nm are generally defined as micropores, those between 2 nm and 50 m are considered to be mesopores, and those greater than 50 nm dimension are described as macropores.

[0004] Commercial activated carbon has been made from material of plant origin, such as hardwood and softwood, corncobs, kelp, coffee beans, rice hulls, fruit pits, nutshells, and wastes such as bagasse. Activated carbon also has been made from peat, lignite, soft and hard coals, tars and pitches, asphalt, petroleum residues, and carbon black.

[0005] Most common commercial grades of activated carbon are available in three forms. These are powdered, granular, or shaped (usually, pelletized). Shaped activated carbons are achieved by extrusion of a blend of powdered activated carbon with bentonite clay through a die. The normal choice of die shape produces a cylindrical pellet. Powdered carbons are finely divided particles having a median particle diameter ranging in size from 20 microns to 50 microns; granular carbons are irregularly shaped particles ranging in size from 0.5 mm to 4 mm; and pelletized carbons are smooth, hard cylinders typically characterized by diameters ranging from 1 mm to 4 mm. Powdered carbons are generally used in liquid-phase applications where the carbon is mixed with the liquid being purified and is then separated from the liquid using filtration technology. Granular carbons are used in both vapor and liquid-phase applications where, again, the carbon is held in a canister or large column. Pelletized carbons are generally used in vapor-phase applications where the carbon is held in a canister or large column.

[0006] The above forms of activated carbon are useful for most applications involving flowing liquid and vapor-phase streams where an activated carbon-filled canister, column, or filtration apparatus can be installed, such as home and municipal water purification, industrial and residential air purification, and purification of in-process streams in food, chemical and pharmaceutical production processes. For other applications which are not amenable to having equipment for containing the carbon, more convenient forms of activated carbon have been developed. These forms include blends of powdered activated carbon and binder that can be applied directly to a variety of pre-formed substrates, thereby eliminating the need for a canister or column-type device to hold pelletized or granular carbon or a filtration device to capture the powdered carbon. This facilitates the use of the activated carbon in such applications as odor control personal care products, odor control packaging, low-pressure adsorbent monolithic structures used in commercial vapor recovery operations, and adsorbent building materials (U.S. Patent Nos. 5,914,294 and 6,284,705).

[0007] Activation of the organic raw material can be accomplished by one of two distinct processes: (1) chemical activation or (2) thermal activation. The effective porosity of activated carbon produced by thermal activation is the result of gasification of the carbon at relatively high temperatures after an initial carbonization of the raw material. The porosity of chemically activated products generally is created by chemical dehydration reactions occurring at significantly lower temperatures. Furthermore, chemical activation process may be performed in the presence of alkali, often known as alkaline activation process (U.S. Patent No. 5,965,483). Activated carbons produced by thermal activation are typically more microporous (i.e., pore size no more than 1.8 nm); while carbons produced by chemical activation are typically more mesoporous (i.e., pore size in a range of above 1.8 nm up to 5 nm). Pore size distribution is often a controlling factor in adsorption of liquid and gas-phase contaminants.

[0008] Mesoporous activated carbon has been known for its effectiveness in several liquid phase and catalytic applications. There has been a continuing effort to develop a production process for mesoporous activated carbon employing carbon precursors that are abundantly available from natural sources. Furthermore, the process is to be lower in cost and easy to implement and amenable to reliable duplication.

[0009] Accordingly, it is an object of the present invention to provide a process for producing mesoporous activated carbon that is simple, highly reproducible and controllable for pore characteristics, and lower in cost. Specifically, the present invention is to provide a process for producing mesoporous activated carbon from a naturally abundant carbon precursor such as carbohydrate. [0010] Another application for activated carbon is used as electrodes for capacitors (U.S. Patent Nos. 5,905,629; 5,926,361; 6,043,183; and 6,060,424). Capacitors such as electron double layer (EDLC) capacitor, ultracapacitor and supercapacitor, are based on double-layer capacitance store energy in a polarized liquid layer only a few angstroms thick at the interface between an ionically conducting electrolyte solution and an electronically conducting electrode. The separation of charge in the ionic species at the interface (called a double layer) produces a standing electric field. If other factors are equal, the larger the electrode surface area the more charge can be stored. In addition, because no chemical reactions take place during the charge/discharge cycle, these devices can be cycled many times without degradation. Typically, capacitors contains at least two such electrodes, at least one porous separator interposed between the at least two such electrodes and an electrolytic solution that is in contact with the at least two such electrode structures and the at least one porous separator. The electrolytic solution for double layer capacitor devices may be aqueous electrolytes such as potassium hydroxide and sulfuric acid, or organic electrolytes such as NEt₄BF₄ dissolved in propylene carbonate or acetonitrile.

[0011] U.S. Patent Application No. 2006/0,093,915 teaches the process of producing activated carbon derived from a carbon precursor selected from naturally occurring carbohydrates, pitch derived from coal tar, pitch derived from petroleum and combinations. Nitrogen functionality compound must be added into the carbon prior to activation process. The required level of incorporated nitrogen functionality is greater than 1.0 wt % elemental nitrogen. U.S. Patent Application No. 2005/0,207,962 teaches that mesoporous activated carbon can be produced from a mixture comprising at least one carbohydrate, at least one dehydrating component, and at least one nonmetallic cationic component. Both of these processes require that a carbon precursor is activated in the presence of additional component or additional step from conventional carbon activation process. Incorporation of nitrogen functionality to the carbon precursor is critical in U.S. Patent Application No. 2006/0,093,915; while in U.S. Patent Application No. 2005/0,207,962 carbon precursor must be mixed with at least one nonmetallic cationic salt and at least one dehydrating component prior to the activation process.

[0012] Therefore, it is an object of the present invention to provide a process for producing activated carbon suitable for use as in capacitor electrode that is simple, highly reproducible and controllable for pore characteristics, and lower in cost. Specifically, the present invention is to provide a process for producing activated carbon from carbohydrate precursor, which is suitable for use as in capacitor electrode, that does not require additional components to carbon precursor or additional step to the conventional carbon activation process.

[0013] It is another object of the present invention is to provide activated carbon derived from a naturally abundant carbon precursor such as carbohydrate, which is suitable for use as in electrodes for energy storage devices.

[0014] It is yet another object of the present invention is to provide a method for producing activated carbon derived from carbohydrate precursor.

[0015] It is a further object of the present invention is to provide an electrode comprising the activated carbon of the present invention.

[0016] It is a yet further object of the present invention to provide energy storage devices such as EDLC and other capacitors, comprising an electrode made from the activated carbon of the present invention.

[0017] Other objects and advantages of the present invention will become apparent from the following detailed description.

SUMMARY OF THE INVENTION

[0018] The objectives of this invention are met by pyrolyzing dewatered carbohydrate carbon precursor, and then activating the obtained carbon material. The produced activated carbon exhibiting internal pore structure and high surface area is suitable for use in multiple liquid and gas adsorptive applications and advantageously in electrodes for energy storage devices. DESCRIPTION OF THE PREFERRED EMBODIMENT

[0019] The advantages and purposes of the invention will be set forth in part in the description which follows, and in part will be obvious from the description, or may be learned by practice of the invention. The advantages and purposes of the invention will be realized and attained by means of the elements and combinations particularly pointed out in the appended claims.

[0020] In one embodiment, the activated carbon of the present invention was prepared by a process comprising:

(a) dewatering carbohydrate precursor under a temperature range of from about 16O⁰C to about 200⁰C in air;

(b) pyrolyzing the dewatered carbon precursor to decomposition, while drawing away decomposition gases to produce an essentially pure carbon material; and

(c) activating the carbon materials using thermal activation or chemical activation.

[0021] The activation process in step (c) may be performed in the presence of carbon dioxide, or high temperature stream, or activating agent selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof. After the activation with activating agent, the activated carbon may be further washed to remove the excess activating agent and then dried.

[0022] In another embodiment, the activated carbon of the present invention was prepared by a process comprising:

(b) pyrolyzing the dewatered carbon precursor to decomposition, while drawing away decomposition gases to produce an essentially pure carbon material; (c) activating the carbon materials using a process selected from the group consisting of thermal activation and chemical activation; and

(d) heat treating the obtained activated carbon at a temperature range from about 45O⁰C to about 1200⁰C.

[0023] The activation process in step (c) may be performed in the presence of carbon dioxide, or high temperature stream, or activating agent selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof. After the activation with activating agent, the activated carbon may be further washed to remove the excess activating agent and then dried.

[0024] In some embodiments, the heat treatment in step (d) may be performed in the presence of at least one compound selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

[0025] The term "carbohydrate" used in the present invention refers to saccharide based compounds including, but are not limited to, monosaccharides such as glucose and fructose; disaccharides such as sucrose and lactose; oligosaccharides and polysaccharides such as starch, corn syrup, and cellulose. Furthermore, these saccharide based compounds may be in form of powder, granular, and syrup.

[0026] The invention activated carbon may be produced or formed into a variety of shapes or objects including, but are not limited to, powders, granules, pellets, blocks, monoliths, sheets, filaments, and tubes.

[0027] The invention activated carbon has a pore size in the range of about 0.8 nm to about 50 nm. The BET surface area of the activated carbon of the present invention ranges from about 500 m²/g to 3,000 m²/g. [0028] The invention activated carbon may be used to produce electrodes for energy storage devices. The term "energy storage devices" in the present invention refers to electron double layer (EDLC) capacitor, ultracapacitor, supercapacitor, battery, fuel cell and any other devices capable of storing energy for systems such as, but are not limited to, automobile and other transportation, power quality, electronic appliances, and power stabilizer devices.

[0029] EDLC capacitor of the present invention contains electrodes, at least one porous separator interposed between the electrodes and an electrolytic solution that is in contact with the electrode structures and the at least one porous separator. Electrolytic solutions may be organic electrolytic solutions and aqueous electrolytic solutions.

[0030] The electrodes comprising typically about 90-95% weight of activated carbon were formed and used for the assembly of EDLC capacitor. The capacitance of the EDLC containing electrodes made of the invention activated carbon were evaluated and compared to those containing electrodes made of activated carbon controls.

[0031] In one embodiment, the activated carbons were obtained from carbon dioxide activation of sucrose precursor at about 95O⁰C for different activation lengths of time: 1 hour, 2 hours, 4 hours and 8 hours. The obtained activated carbon from different activation length of time, each was formed into electrodes typically comprising about 90-95% weight of activated carbon. The EDLC capacitors were assemblies using electrodes made of activated carbon from different activation time length. The capacitance of these EDLC cells were compared to each other, and to those of the EDLC containing electrodes made of activated carbon controls. Three activated carbon controls were used for comparison: YP- 17, RP- 15, and RP-20; all are commercially available from Kuraray. Specifically, RP -20 activated carbon from Kuraray has been well-considered as the best known carbon for the EDLC electrode application. Both electrode capacitance and electrolyte decomposition voltage of the capacitor cells (EDV) were measured for determination of the EDLC energy capacity. (TABLE I) [0032] EDLC capacitor having electrodes made of activated carbon from sucrose precursor under 2-hour carbon dioxide activation showed the highest cell energy of 47.8 J/cc. The cell energies of EDLC capacitors containing sucrose-based activated carbon were 29.0 J/cc for 1-hour activation, 32.7 J/cc for 4-hour activation, and 31.3 J/cc for 8-hour activation.

[0033] Furthermore, EDLC containing electrodes made of sucrose precursor under 2- hour carbon dioxide activation showed superior cell energy to those containing electrodes made of commercial activated carbons YP- 17 and RP-15. EDLC containing electrodes made of activated carbon from sucrose precursor at the optimum activation condition showed comparable cell energy to that of EDLC made of RP-20 which is the best known activated carbon for the EDLC application.

TABLE I

[0034] In one embodiment, the activated carbons were obtained from alkaline activation of sucrose precursor using potassium hydroxide (KOH). The activated carbon was formed into electrodes which were subsequently assembled to EDLC capacitor. The capacitance of the EDLC cell was measured and compared to those of the EDLC containing electrodes made of activated carbon controls. Four alkali activated carbons were used as controls: activated carbon from coke; coconut-based activated carbon NACAR G210 commercially available from PICA, another coconut-based activated carbon from PICA, and activated carbon from Rayonier fly ash. Both electrode capacitance and electrolyte decomposition voltage of the capacitor cell (EDV) were measured for determination of the EDLC energy capacity. (TABLE II)

TABLE II

[0035] EDLC containing electrodes made of sucrose-derived alkali activated carbon showed superior cell energy to those of control.

[0036] The invention activated carbon was also used as electrode for battery. The capacity of battery was measured both for irreversible capacity and reversible capacity at different heat treatment temperature (HTT). Furthermore, the γ value which is a ratio of reversible capacity to irreversible capacity was determined and compared to those of battery using conventional electrode. (TABLE III) TABLE III

[0037] The γ values of the batteries containing electrodes made of the invention activated carbon ranged from about 2 to about 14, based on the heat treatment temperature. Conventional cobalt electrode systems have γ values of 13-14 and Ni electrode systems 5-6; therefore, the invention activated carbon can be used as electrode for battery having the capacity tailored to match those of the conventional systems using cobalt or Ni electrode.

[0038] The foregoing description relates to embodiments of the present invention, and changes and modifications may be made therein without departing from the scope of the invention as defined in the following claims, as claimed.

Claims

What Is Claimed Is:

1. Activated carbon derived from carbon precursor, wherein the carbon precursor comprises carbohydrate selected from the group selected from the group consisting of monosaccharide, disaccharide, oligosaccharide, polysaccharide, and derivatives thereof.

2. The activated carbon of claim 2, wherein the monosaccharide comprises a member selected from the group consisting of fructose, glucose, galactose, and mixture thereof.

3. The activated carbon of claim 2, wherein the disaccharide comprises a member selected from the group consisting of sucrose, maltose, lactose, and mixture thereof.

4. The activated carbon of claim 2, wherein the polysaccharide comprises a member selected from the group consisting of corn syrup, high-fructose corn syrup, starch, cellulose, and mixture thereof.

5. The activated carbon of claim 2, wherein the derivative comprises a member selected from the group consisting of glyceraldehydes, dihydroxyacetone, cellobiose, and mixture thereof.

6. The activated carbon of claim 1, wherein the activated carbon is shaped into a member selected from the group consisting of powder, granular, pellet, sheet, block, filament, tube, monolith, and combination thereof.

7. The activated carbon of claim 1, wherein the activated carbon has a BET surface area range from about 500 m²/g and about 3000 m²/g.

8. The activated carbon of claim 1, wherein the activated carbon has a pore size range from about 0.8 nm to about 50 nm.

9. Activated carbon produced by a process comprising:

(a) under a temperature range of from about 16O⁰C to about 200⁰C in air, dewatering the carbon precursor comprises the carbohydrate selected from the group consisting of monosaccharide, disaccharide, oligosaccharide, polysaccharide, and derivatives thereof;

(c) activating the carbon materials using a process selected from the group consisting of thermal activation and chemical activation.

10. The activated carbon of claim 9, wherein the activation in step (c) is performed in the presence of at least one member selected from the group consisting of carbon dioxide, and high temperature stream, and activating agent.

11. The activated carbon of claim 10, wherein the activating agent is selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

12. The activated carbon of claim 9, wherein at least one of the carbohydrate is selected from the group consisting of sucrose, fructose, glucose, galactose, maltose, lactose, corn syrup, starch, cellulose, and combination thereof.

13. The activated carbon of claim 9, wherein the activated carbon is shaped into a member selected from the group consisting of powder, granular, pellet, sheet, block, filament, tube, monolith, and combination thereof.

14. The activated carbon of claim 9, wherein the activated carbon has a BET surface area range from about 500 m²/g and about 3000 m²/g.

15. The activated carbon of claim 9, wherein the activated carbon has a pore size range from about 0.8 nm to about 50 nm.

16. The activated carbon produced by a process comprising: (a) under a temperature range of from about 16O⁰C to about 200⁰C in air, dewatering the carbon precursor comprises the carbohydrate selected from the group consisting of monosaccharide, disaccharide, oligosaccharide, polysaccharide, and derivatives thereof;

(b) pyrolyzing the dewatered carbon precursor to decomposition, while drawing away decomposition gases to produce an essentially pure carbon material;

(c) activating the carbon materials using a process selected from the group consisting of thermal activation and chemical activation; and

17. The activated carbon of claim 16, wherein the activation in step (c) is performed in the presence of at least one member selected from the group consisting of carbon dioxide, and high temperature stream, and activating agent.

18. The activated carbon of claim 17, wherein the activating agent is selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

19. The activated carbon of claim 16, wherein the heat treatment in step (d) is performed in the presence of at least one compound selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

20. The activated carbon of claim 16, wherein at least one of the carbohydrate is selected from the group consisting of sucrose, fructose, glucose, galactose, maltose, lactose, corn syrup, starch, cellulose, and combination thereof.

21. The activated carbon of claim 16, wherein the activated carbon is shaped into a member selected from the group consisting of powder, granular, pellet, sheet, block, filament, tube, monolith, and combination thereof.

22. The activated carbon of claim 16, wherein the activated carbon has a BET surface area range from about 500 m²/g and about 3000 m²/g.

23. The activated carbon of claim 16, wherein the activated carbon has a pore size range from about 0.8 nm to about 50 nm.

24. An electrode comprising the activated carbon derived from the carbon precursor, wherein the carbon precursor comprises the carbohydrate selected from the group consisting of monosaccharide, disaccharide, oligosaccharide, polysaccharide, and derivatives thereof.

25. The electrode of claim 24, wherein at least one of the carbohydrate is selected from the group consisting of sucrose, fructose, glucose, galactose, maltose, lactose, corn syrup, starch, cellulose, and combination thereof.

26. The electrode of claim 24, wherein the activated carbon has a BET surface area range from about 500 m²/g and about 3000 m²/g.

27. The electrode of claim 24, wherein the activated carbon has a pore size range from about 0.8 nm to about 50 nm.

28. The electrode of claim 24, wherein the activated carbon is produced by a process comprising:

(a) dewatering the carbohydrate carbon precursor under a temperature range of from about 16O⁰C to about 200⁰C in air;

29. The electrode of claim 28, wherein the activation in step (c) is performed in the presence of at least one member selected from the group consisting of carbon dioxide, and high temperature stream, and activating agent.

30. The electrode of claim 29, wherein the activating agent is selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

31. The electrode of claim 24, wherein the activated carbon is produced by a process comprising:

(a) dewatering the carbohydrate precursor under a temperature range of from about 16O⁰C to about 200⁰C in air;

32. The electrode of claim 31, wherein the activation in step (c) is performed in the presence of at least one member selected from the group consisting of carbon dioxide, and high temperature stream, and activating agent.

33. The electrode of claim 32, wherein the activating agent is selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

34. The electrode of claim 31 , wherein the heat treatment in step (d) is performed in the presence of at least one compound selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

35. An energy storage device including at least one electrode comprising that activated carbon derived from the carbon precursor, wherein the carbon precursor comprises the carbohydrate selected from the group consisting of monosaccharide, disaccharide, oligosaccharide, polysaccharide, and derivatives thereof.

36. The energy storage device of claim 35, wherein at least one of the carbohydrate is selected from the group consisting of sucrose, fructose, glucose, galactose, maltose, lactose, corn syrup, starch, cellulose, and combination thereof.

37. The energy storage device of claim 35, wherein the activated carbon has a BET surface area range from about 500 m²/g and about 3000 m²/g.

38. The energy storage device of claim 35, wherein the activated carbon has a pore size range from about 0.8 nm to about 50 nm.

39. The energy storage device of claim 35, wherein the activated carbon is produced by a process comprising:

40. The energy storage device of claim 39, wherein the activation in step (c) is performed in the presence of at least one member selected from the group consisting of carbon dioxide, and high temperature stream, and activating agent.

41. The energy storage device of claim 40, wherein the activating agent is selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

42. The energy storage device of claim 35, wherein the activated carbon is produced by a process comprising:

43. The energy storage device of claim 42, wherein the activation in step (c) is performed in the presence of at least one member selected from the group consisting of carbon dioxide, and high temperature stream, and activating agent.

44. The energy storage device of claim 43, wherein the activating agent is selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

45. The energy storage device of claim 42, wherein the heat treatment in step (d) is performed in the presence of at least one compound selected from the group consisting of alkali metal hydroxides, carbonates, sulfides, and sulfates; alkaline earth carbonates, chlorides, sulfates, and phosphates; phosphoric acid; polyphosphoric acid; pyrophosphoric acid; zinc chloride; sulfuric acid; oleum; and combinations thereof.

46. The energy storage device of claim 35, characterized as capacitor.

47. The energy storage device of claim 35, characterized as double layer capacitor.

48. The energy storage device of claim 35, characterized as battery.