阅读说明：本技术 碳粉末及其制备方法 (Carbon dust and preparation method thereof ) 是由 R·巴塞尔 R·克拉克 A·哥斯河 D·米勒 于 2018-02-06 设计创作，主要内容包括：一种制备具有确定碳粒度分布的碳粉末的方法,包括如下步骤：-a)选择具有确定的前体粒度分布的碳前体粉末,所述碳前体粉末由一种或多种可熔化碳前体的颗粒组成或包含一种或多种可熔化碳前体的颗粒；b)处理所述碳前体粉末以使所述碳前体的所述颗粒中的至少一些变圆,并从而产生圆形碳前体；以及c)使所述圆形碳前体碳化；其中所述确定的前体粒度分布使得在碳化时产生所述具有确定碳粒度分布的粉末。(A method of it prepares with the carbon dust for determining carbon size distribution, include the following steps:-a) carbon precursor powder of the selection with determining precursor particle size distribution, the carbon precursor powder is made of the particle of one or more fusible carbon precursors or the particle comprising one or more fusible carbon precursors；B) the carbon precursor powder is handled so that at least some of the particle of the carbon precursor is rounded, and thereby generates round carbon precursor；And the round carbon precursor c) is made to be carbonized；Wherein the precursor particle size of the determination is distributed so that generating the powder for having and determining carbon size distribution in carbonization.)

1. a kind of method prepared with the carbon dust for determining carbon size distribution, the described method comprises the following steps :-

A) selection has the carbon precursor powder of determining precursor particle size distribution, and the carbon precursor powder is by one or more fusible The particle of carbon precursor forms or the particle comprising one or more fusible carbon precursors；

B) the carbon precursor powder is handled so that at least some of the particle of the carbon precursor is rounded, and thereby generates circle Shape carbon precursor；And

C) the round carbon precursor is made to be carbonized；

Wherein the precursor particle size of the determination is distributed so that generating the powder for having and determining carbon size distribution in carbonization.

2. the method as described in claim 1, wherein the step of providing the carbon precursor powder with determining precursor particle size distribution The following steps are included:-

A) providing has the first the first carbon precursor powder for determining size distribution；And

B) particle of the selection with the second size distribution than first narrow particle size distribution from the carbon precursor powder, to produce The raw carbon precursor powder with determining precursor particle size distribution.

3. method according to claim 2, wherein the step of selecting from the carbon precursor powder includes screening described first Carbon precursor powder.

4. such as claim 2 or method as claimed in claim 3, wherein the first carbon precursor powder includes being injected into shape powder End.

5. the method as described in any one of claim 2 to 4, wherein providing has the first carbon precursor powder for determining size distribution The step at end includes initial carbon precursor powder of milling.

6. the method as described in any one of claims 1 to 5, wherein handling the carbon precursor powder so that in the particle At least some steps being rounded include the steps that at least one mills in a mild condition.

7. such as method described in any one of claims 1 to 6, wherein handling the carbon precursor powder so that in the particle At least some steps being rounded include that at least one at least partly makes of one or more fusible carbon precursors The step of grain fusing.

8. the method as described in any one of claims 1 to 7, wherein handling the carbon precursor powder so that in the particle At least some steps being rounded include one or more that at least one is at least partly pyrolyzed the carbon precursor powder The step of grain.

9. such as method described in any item of the claim 1 to 8, wherein handling the carbon precursor powder so that in the particle At least some steps being rounded include at least one wherein the carbon precursor powder is added while being suspended in fluid The step of heat.

10. method as claimed in claim 9, wherein the fluid is selected from water, glycerol, mineral oil, glycol, alcohol, silicone oil and has One of machine acid is a variety of.

11. such as claim 9 or method described in any one of claim 10, wherein the fluid includes one or more surfactants And/or viscosity modifier.

12. the method as described in any one of claim 9 to 11, wherein the temperature of the fluid is being lower than the carbon precursor powder In the range of 50 DEG C of fusing point of end to the immediately lower than fusing point of the carbon precursor powder.

13. the method as described in any one of claim 9 to 12, wherein it is described to keep the carbon precursor to be suspended in using agitation In fluid.

14. the method as described in any one of claims 1 to 13, wherein handling the carbon precursor powder so that in the particle At least some steps being rounded include the steps that wherein spraying the carbon precursor powder.

15. the method as described in any one of claims 1 to 14, wherein handling the carbon precursor powder so that in the particle At least some steps being rounded include the steps that wet-milling spheroidization.

16. the method as described in any one of claim 2 to 17, wherein will belong to than described in first narrow particle size distribution Particle refuse other than second size distribution, and milled and be used as one of at least described first carbon precursor powder Point.

17. the method as described in any one of claims 1 to 16, wherein one or more carbon precursor powder include one kind Or a variety of selected from the following group of precursors: pitch, polymer, sugar, vinyl esters, polyacrylonitrile, polyethylene terephthalate, Nylon (polyamide), polyethylene, polypropylene, polyvinyl chloride, polystyrene, polyurethane, furfural, naphthalene, cellulose, cellulosic plastics And artificial silk.

18. method as claimed in claim 17, wherein using one or more pitches, the fusing point of at least one pitch therein Lower than 350 DEG C.

19. method as claimed in claim 18, the fusing point of wherein at least one pitch is in the range of 70-250 DEG C.

20. the method as described in any one of claims 1 to 19, wherein fine particles material is added to the carbon precursor powder In.

21. method as claimed in claim 20, wherein handling the carbon precursor powder so that in the particle of the carbon precursor It is at least some be rounded before or while the fine particles material is added in the carbon precursor powder, to reduce the carbon The reunion of precursor.

22. the method as described in claim 20 or claim 21, wherein the fine particles material includes by any aforementioned A part of the powder of the method for claim preparation, size distribution are less than the determining carbon size distribution.

23. the method as described in any one of claim 1 to 22, the method also includes wherein making the circle before carbonization Shape carbon precursor stabilizes the step of to limit the refuse during carbonization.

24. method as claimed in claim 23, wherein stabilize include at least one be exposed to nitric acid, air, hydrogen peroxide, One of ozone and sulfuric acid or a variety of steps.

25. the method as described in claim 23 or claim 24, wherein using two or more stabilization steps.

26. the method as described in any one of claim 1 to 25, wherein after carbonization, the carbonized particles are further One or more steps before carbonization and/or graphitization in experience infiltration, coating or vacuum deposition.

27. the method as described in any one of claim 1 to 26, the method includes other steps, wherein the carbon quilt Activation is to provide high surface area and porosity.

28. the method as described in any one of claim 1 to 27, wherein the carburising step is or including graphitization step.

29. the method as described in claim 1 to 28, wherein the carbon precursor powder also includes graphitization catalyst.

30. method as claimed in claim 29, wherein the graphitization catalyst include boron, aluminium, titanium, manganese, iron, nickel, titanium with And one of their chemical derivative or a variety of.

31. the method as described in any one of claims 1 to 30, wherein the carbon precursor powder also includes catalyst component.

32. method as claimed in claim 31, wherein the catalyst component includes copper, silver, tin, antimony, silicon and their change Learn one of derivative or a variety of.

33. the method as described in any one of claims 1 to 32, wherein the carbon precursor powder also includes one or more receives Rice material.

34. method as claimed in claim 33, wherein the nano material includes nano particle, nanotube, nano-sized carbon, graphite One of alkene, graphene oxide, derivatization graphene, cellulose, elemental constituent and clay are a variety of.

35. the method as described in any one of claims 1 to 34, wherein the carbon precursor powder also includes one or more shadows The additive of structure during the sound stabilisation and/or the carburising step.

36. method as claimed in claim 35, wherein one or more additives include phenolic resin, ester, furfural, One of naphthalene, sulphur, sulfonic acid and organic catalyst are a variety of.

37. the method as described in claim 35 or claim 36, the method also includes extraction steps to remove described one At least some of kind or multiple additives.

38. the method as described in any one of claims 1 to 37, wherein using at least one purification step after carbonization.

39. method as claimed in claim 38, wherein being carried out after graphitization step at least one described purification step At least one.

40. a kind of method, described method includes following steps: will pass through method system described in any one of claims 1 to 39 Standby has two or more carbon dusts mixing for determining carbon size distribution, to be obtained by described two or more carbon dusts The carbon dust being distributed with different determination carbon granules degree.

41. the method as described in any one of Claims 1-4 0, wherein described have the carbon dust tool for determining carbon size distribution Have such size distribution: wherein at least 95% powder includes average largest diameter in 5-50 μ m by volume Particle, wherein at least 90% powder has the maximum gauge within the 40% of the range ± average value.

42. method as claimed in claim 41, wherein the carbon dust with determining carbon size distribution has such grain Degree distribution: wherein at least 95% powder includes particle of the maximum gauge in 10-30 μ m by volume, wherein extremely Few 90% powder has the maximum gauge within the 40% of the range ± average value.

43. a kind of equipment comprising be configured to realize the one or more of method described in any one of Claims 1-4 2 Grinding machine, one or more sieves, one or more stoves and one or more rounding devices.

It is by will be a kind of or more 44. the material that one kind can be obtained by the method described in any one of Claims 1-4 2 Kind graphitization catalyst is incorporated into the customization of manufactured non-graphitized carbon (hard carbon) and graphitic carbon material in the carbon precursor Mixture.

45. material as claimed in claim 44, wherein the graphitization catalyst include boron, aluminium, titanium, manganese, iron, nickel, titanium with And their chemical derivative and one of compound or a variety of.

46. one kind can the material as made from the method described in any one of Claims 1-4 2, wherein blast blending, with Change carbon graphite in the anode material being used as the material in lithium ion battery, sodium-ion battery or Magnesium ion battery to urge Change surface and/or increase the reversible capacity of the material (relative to pure graphite).

47. material as claimed in claim 46, wherein the additive includes aluminium chloride, carbon black, powdered graphite, copper and copper Salt, silver and silver salt, tin, antimony and silicon and one of their chemical derivative and compound or a variety of.

48. the material that one kind can be obtained by the method described in any one of Claims 1-4 2, wherein the carbon precursor powder It also include one or more nano materials.

49. material as claimed in claim 48, wherein the nano material includes nano particle, nanotube, nano-sized carbon, graphite One of alkene, graphene oxide, derivatization graphene, cellulose, elemental constituent and clay are a variety of.

50. the material that one kind can be obtained by the method described in any one of Claims 1-4 2, wherein the carbon precursor powder Additive also comprising the structure during one or more influence stabilisations and/or the carburising step.

51. material as claimed in claim 50, wherein one or more additives include phenolic resin, ester, furfural, One of naphthalene, sulphur, sulfonic acid and organic catalyst are a variety of.

52. a kind of electrochemical cell, the electrochemical cell is mixed with material described in any one of claim 44 to 51.

Background technique

Past produces always carbon graphite powder using the carbon of many types.This kind of powder is generally but not used only for urging Change and electrochemical applications, such as in the battery.Carbon graphite powder is currently used as lithium-absorbing material, used in the electricity of lithium ion battery In extremely.The present invention is not limited to any special-purposes, and may extend into wherein to have and determine that the carbon particle of size distribution is closed Any application field of note.

The problem of preparing lithium ion battery or other catalytic surfaces first is that filling and packaging Problems.It is answered in lithium ion battery It the use of be highly susceptible to filling and still there is the carbon of good charge/discharge characteristics is useful in.For this purpose, generally remaining Small powder surface area, and tap density and compacted density are ideally higher.In catalytic applications, different standards may be fitted With.

This means that the granularity of the carbon material of many application preparations must be properly adjusted within the scope of stringent limitation To obtain good performance.In some applications, this preferably realized using two different granularities (Nagarajan, G.S., J.W.Van Zee and R.M.Spotnitz.1998.J.Electrochem.Soc.145 (3): 771-779).Particle structure Type influences compacted density, tap density and general quality, such as absorption or catalytic property.

Therefore, carbon dust granularity is for suitably preparing material used in controlled porosity material, battery and for capacitor It is most important for device and the carbon products of other stored energy applications and catalytic applications.

For lithium ion battery and other battery applications, graphite particle is faced with some problem, including their appearance Measure it is limited, and they be easy peeled off by electrolyte.In this applications, so-called " hard carbon " is preferred, and for one For a little applications, [sodium ion and Magnesium ion battery] may be necessary.In addition to high capacity relevant to hard carbon is (relative to graphite For) except, hard carbon also allow under the voltage higher than graphite run-to higher voltage-transition be lithium ion battery industry Visible trend.

The present invention is suitable for preparing hard carbon, but can also be used for preparing graphite；Or even it is used to prepare hard carbon and graphite Mixture to adjust capacity and voltage's distribiuting on demand.

Some definition of term used in this specification are easily introduced herein.

Definition :-

" spheroidization "-is rounded particle and is shaped to aspect ratio [the longest axis: most short axle] less than 10:1 or is less than 5:1 or small In 3:1 or less than the process of 2:1.Aspect ratio is represented by two numbers separated by colon or is expressed as the simple or decimal system Decimal.

The material of " nano material "-containing particle, the particle are in unbound state or as aggregation or conducts Aggregate, and wherein for 50% or more particle in quantity size distribution, one or more external dimensions are in 1nm- In the particle size range of 100nm.

" stabilisation "-It can be so as to carrying out chemical modification to pitch or other precursors so that it will not refuse in carbonization Process.This can be considered as being crosslinked materials chemistry to retain structure feature, it can locking is easy to graphited pitch knot Structure, or can lock will not graphited bituminous texture.This is dripped with isotropic pitch fiber and interphase What green fiber was completed.

Most of carbon and powdered graphite are milling made of massive material.Used grinding machine is different, but all Material fragmentation and successive granularity is caused to reduce.All milling unit operations with narrow size distribution and have circle for preparation It or is still faulty mode for the particle of circular shape.

When mill carbon when, granularity can be readjusted and carbon of milling again, until obtaining no more than granularity needed for maximum Particle.However, milled to preforming carbon and spheroidization (rounding) the result is that forming the particle smaller than required granularity, shape The irregular non-circular particle of shape is also such.This kind of particle becomes waste material, and improves production/processing cost.

In addition, granularity appropriate and aspect ratio are extremely important for the filling of round powder and performance.Therefore, pass through Suitable mode will be used for the carbon dust spheroidization of many applications.

Alternatively, particle can be made to be rounded before being converted to carbon.It is used to keep particle smooth at present and keeps them substantially round The method of shape causes generated most of substance to include the powder less than ideal particle size range.In these many applications, There is 30-70% smaller than granularity appropriate in gained carbon, or is not appropriate spherical form.

It can also be by carrying out spheroidization at the end of shape obsolete preparation or preparing agglomerated particle before carbonization come real The preparation of existing suitable ball particle.

Coating and agglomeration techniques are known (US 3891574；US 4371454；US 7148285B2；US 5480626).Although it is possible to obtain lesser particle and prepare the agglomerated materials with appropriate particle size range, but this again There are problems for kind technology.This not only results in that step is more, and the process of reunion can lead to particle surface area with higher, reason The voidage for being particle can be with such as phenolic substances, polymer, pitch, sugar and by the coherent other chemicals of particle The material of matter sticks together, and often expand and result in higher than the desirable surface area of gained particle.In addition, because making It may be squeezed with period particle, it is possible that the problem of depositing in terms of intensity.This extruding may crush of reunion Grain leads to relaxation expansion and other problems.

In the past, other methods for the granularity and shape that control carbon graphite particle are to prepare mesophase globule, are extracted Remaining pitch, and these spheres are separated, it stabilized, be carbonized and be graphitized later.These spheres boil the phase in pitch Between self-assembling formation.These mesophase globules are partially oxidized, therefore than the pitch of surrounding more resistant to oxidation and fusing, and are less susceptible to Dissolution.In fact, their structure is fixed, and melt suppressed.The technology of this circular granular is prepared in patent document It is known in (EP0456278B1, EP1296892A4, US4045368, US4273675 etc.).In some journal of writings and opinion Also to these techniques have been summary (Zhou, Changjun.2007.The effect of additives and in text processing conditions on properties of sintered mesocarbon microbeads.Dissertation Notre Dame,IN；Norfolk, C. et al., 2004.Carbon42 (1): 11-19； Chang, Y. et al., 1999.Carbon 37 (8): 1285-1297；Korai, Y. et al., 1997.Carbon 35 (10-11): 1503-1515；Wang.Y. et al., 1999.Carbon37 (2): 307-314；Park,S.H.2001.Carbon 2(2):99- 104)。

Most of technology is concentrated on keeps the sphere with appropriate granularity raw by suitably boiling with solvent/solute selection It is long, unoxidized pitch is then extracted, pitch particle separable whereby is for further aoxidizing and stabilizing.When doing so When, due to forming porosity, this often leads to particle surface area with higher.Mesophase globule is used according to these methods, The yield of circle carbon dust with appropriate granularity is too low, causes the price of these products very expensive, this is because having suitably The particle yield of granularity is lower, and solvent and processing cost are higher.

Prepare circular granular second of known method be by mold squeeze out pitch or suitably can char-forming material, by it Be cut into various length, and will cutting but fusing particle after its having time spheroidization cooling (US 4371454, US 7781370).This method is expensive, and is dfficult to apply to very small granularity.

There are many trials that spherical carbon particle is prepared also by molding or dispersion.These are also the master of many patents Inscribe (US 3909449；US 3953345；US 4025689；U. S. application 2010/0311852A1；U. S. application 2012/ 0286216A1；EP1743870A1).These technologies allow to prepare numerous particles having from nanometer to mm particle size.However, These methods are expensive, and generate the particle of modified granularity, orientation plane, surface nature and catalytic activity.Tool The particle of inappropriate granularity is difficult to be utilized, and cannot be recovered.

Aeroge is prepared as the method (US5898564) for preparing circle carbon particle it is also proposed that crossing.

Summary of the invention

Inventors have realised that by the carbon precursor rounding for making that there is appropriate size distribution, so that it is in carbonization Reach required carbon size distribution, it can be to avoid a large amount of wastes.

Therefore, the present invention includes the method that preparation has the carbon dust for determining carbon size distribution, and the method includes as follows Step :-

A) selection has the carbon precursor powder of determining precursor particle size distribution, and the carbon precursor powder is by fusible carbon precursor Particle composition or the particle comprising fusible carbon precursor；

B) the carbon precursor powder is handled so that at least some of the particle of the carbon precursor is rounded, and thereby is produced Raw circle carbon precursor；And

C) the round carbon precursor is made to be carbonized；

Wherein the precursor particle size of the determination is distributed so that generating the powder for having and determining carbon size distribution in carbonization End.

The step of providing the carbon precursor powder with determining precursor particle size distribution can be for example including following steps :-

A) providing has the first the first carbon precursor powder for determining size distribution；And

B) particle of the selection with the second size distribution than first narrow particle size distribution from the carbon precursor powder, To generate the carbon precursor powder with determining precursor particle size distribution.

And it can be for example including screening the first carbon precursor powder.

The step of providing the carbon precursor powder with the first determining size distribution may include initial carbon precursor powder of milling.

Processing has the carbon precursor powder of specified particle size so that at least some of described particle can be such as the step of being rounded Include the steps that one or more from the following group :-

It mills in a mild condition；

Melt the particle of the fusible carbon precursor at least partly.

The carbon precursor powder is handled so that the step of at least some of described particle is rounded can be for example including wherein general The step of carbon precursor powder suspends in a fluid.The step for may include wet-milling spheroidization.

Generated carbon particle or round carbon precursor particle preferably have less than 2.0；Or less than 1.8；Or less than 1.6；Or Less than 1.4；Or less than 1.2；Or the aspect ratio less than 1.1.

Rounding processing preferably makes carbon particle or the aspect ratio of carbon precursor particle reduce at least 20%；Or at least 40%；Or At least 60%；Or at least 80%.

The disclosure is further described in the claims, and only by way of example following non-limiting It is further described in description and with reference to attached drawing, in which:-

Fig. 1 discloses the flow chart of the method for non-limiting embodiments according to the present invention

Fig. 2 shows the spheroidization carbon made of rounding according to the present invention

Fig. 3 shows asphericalization carbon

Fig. 4 shows embodiment spheroidization carbon made of the rounding in glycerol according to the present invention

Preparation is outlined in Fig. 1 to be had specified particle size and is the technique of circular carbon graphite.In the method shown in, Selection enters the carbon precursor 1 of preparation step 2, and the carbon precursor can be crushed in this step, and as described below with optionally at Divide and reprocessing material mixes.Then carbon precursor goes to mill step 3 and screening step 4, obtains having determining carbon precursor granularity The carbon precursor powder of distribution.As further discussed below, it is not belonging to determine the particle within carbon precursor size distribution It is sent back in preparation step 2 to be reprocessed.

It really belongs to determine that the particle within carbon precursor size distribution is transferred to rounding step 5, and is transferred to therefrom into one The screening step 6 of step.It is not belonging to determine that the particle within carbon precursor size distribution is sent back to preparation step 2, there their quilts Refuse simultaneously crushes.

It really belongs to determine that the particle within carbon precursor size distribution is transferred to stabilization step 7, and is transferred to carbonization therefrom Step 8.

It can provide optional graphitization step 9.

Carbonization or graphitization particle go to final screening step 10.Meeting required carbon size distribution, (it can be with following institute The determination carbon precursor size distribution stated is identical or different) carbonization or graphitization particle as final product be transferred to 11, can original Sample uses, or is blended as needed with other materials.

It can be in step 12 by the carbonization or graphitization particle reprocessing that meet required carbon size distribution [such as by milling And screening] and be transferred to preparation step 2, to be incorporated into the precursor powder of fusible ingredient.

Optional component 13 can be mixed in preparation step, and can mix optional component in stabilisation or carburising step 14。

Several steps in these steps be it is optional, depending on the property of raw materials and sought product, under Face provides further details.

The preparation of carbon precursor.Typical process of the invention will start from carbon precursor of the selection with determining precursor particle size distribution Powder.The carbon precursor powder being distributed with determining precursor particle size can be the product with appropriate size distribution bought, But it will usually be started with the product of purchase, the product of the purchase will be milled and sieve (step 3 of milling and screening step 4).

Carbon precursor powder includes one or more fusible carbon precursors [such as pitch or polymer].It can will be before fusible carbon Body refuse simultaneously adds other element.Although many polymer and other materials can be used as precursor, usual pitch is most Cheap fusible precursor.As discussed below, carbon precursor powder may also comprise and not be fusible component, such as can not The precursor and carbon dust of fusing.The carbon of reprocessing can be returned and be mixed in mixture.

The pitch from coal or petroleum can be used, and they can be higher than 350 DEG C from changing at room temperature for liquid Lower fusing.It is at room temperature preferably as it can be for the pitch of solid (such as fusing point be higher than 30 DEG C or be higher than 50 DEG C) It mills in the case where without specially cooling down.Although refined bitumen can be used, isotropism and mesophase pitch are more convenient. Although for some products, the pitch with naphthalene and anthracene can be used usually using unmodified pitch.Preferred pitch It may include that process of the fusing point between 110 DEG C and 300 DEG C mills and have the pitch of specified particle size.Most of softening points are in 230- Pitch within the scope of 280 DEG C is considered as interphase.

Optional component 13 can be added in this stage.The example of the material of catalyzed graphitization have metal and boron, aluminium, titanium, vanadium, Manganese, iron, nickel, the compound of silicon, silicon carbide and other silicon compounds that silicon is discharged in burning.Preferred additive includes member One of aluminium, boron, silicon, tin or titanium of element or combined form is a variety of.Hydrogen fluoride and boron trifluoride (can also be recovered) also one Directly it is used as graphitization catalyst.The suitable addition of graphitization catalysis material can be used for preparing hard carbon and the graphitic carbon mixing of customization The material of object, the material have an advantage compared with pure graphite material in terms of voltage's distribiuting and reversible capacity raising, and with work For the active material in lithium ion battery hard carbon material compared to have the advantages that irreversible capacity reduce.In such as sodium ion and The similar inside battery of Magnesium ion battery will have similar feature performance benefit.Other additives also contribute to improving carbon graphite catalysis The performance on surface, such as aluminium chloride (being added as catalyst), carbon black, powdered graphite, copper or mantoquita (for increasing capacity), silver With silver salt, tin, antimony and silicon.When the anode material being used as in lithium ion battery, sodium-ion battery or Magnesium ion battery, these add Add some reversible capacities that will also will increase material in agent.Optimal material will depend on the final use of carbon graphite, and Not limited to this inventory.

In order to change the property of stabilizing material, phenolic resin, ester, furfural, naphthalene and many other ingredients and pitch can be made It is blended.Some possible needs in these substances extract after spheroidization, and will affect the surface area of final product.

The rework of preforming graphite or other carbon can be incorporated into pitch.These particles should be preferably particle It is preferred that at most 1/the 5 of final size.Can produce in this way can by by multiple surfaces and pore structure formed in material come Improve the hybrid orientation of catalytic activity.The interface of these different surfaces can also become the region of increased activity.

Discovery addition nano material and structure (such as nano material based on carbon and other elements) help to improve recently The property of carbon.Graphene film is a kind of such nano material, can be added in precursor to improve surface nature.This Outside, sulphur, sulfonic acid and various other components may act as processing aid, and influence final physics and chemical property.[such as The chemical substance cross-linked bitumen listed in US5607770 is to be made hard carbon].

It may also comprise in carbon precursor and be not fusible carbon precursor [such as cellulose].

Adjust the granularity of carbon precursor.As described above, being carbonized with reasonable carbon yield into available precursors by milling and sieving Pitch or other materials prepare the particle of appropriate particle size range.It is different from other methods of spheroidization particle are prepared, this hair It is bright to be prepared so that screening and other particle size separation methods appropriate [such as injection screening or any other suitable method] passed through The carbon precursor particle with appropriate granularity start.

If grain graininess is inappropriate, the fusible carbon precursor particles fuse of specification can be will exceed and milled again. This makes it possible to obtain the particle of the very appropriate particle size range of high yield first.Once obtaining of appropriate particle size range Grain then can carry out spheroidization to them using mild grinding equipment or be rounded them, and will exceed the particulate weight of specification Newly melts and reuse.Alternatively, can be in the solution or by other suitable methods (including wet process spheroidization) to them Carry out spheroidization.

Not fusible carbon precursor does not have this advantage, but can will exceed the particle of specification and be fusible combination of precursors conduct Raw material is reused.

The spheroidization of base particle.It can be further processed by one of two kinds of major ways this fusible with specified particle size Change carbon precursor particle.Starting Particle can be made to be rounded in the solution or by Starting Particle dry grinding or wet-milling, by its spheroidization, it It is stabilized afterwards.Because pitch is still easy to melt, can will lay equal stress on from the particulate fusing less than particle size range milled Newly mill.For wet-milling, the slurry of particle can be put into solution and be pumped.Pumping technology can make particle with the time Passage rounding.This can also be assisted by on-line mixing appropriate, by on-line mixing particles hit hard surface or each other It hits.Needle mill or emulsification grinding machine are especially suitable for this purpose.Paddle grinding machine or variable-speed mill are suitable for dry grinding.There are many not Same grinding machine is suitable for this step.

Alternatively, can be in the solution by spheroidizing of particles.What this was usually completed in the following way, i.e., particle is suspended In the solution, with immediately lower than fusion temperature is mixed and heated, so that particle is rounded.Such as the heated more or mistake of fruit granule Long, then particle will be agglomerated into not available agglomerate.As fruit granule is not heated the sufficiently long time or not stirring In the case of heat, then they will not become spherical.Applicable condition will change according to the property of precursor.

The rounding dicyandiamide solution appropriate dependent on selection in the solution.Pitch and solvent need to match.Ideally, Solvent should be it is viscous enough, with help to maintain particle separate.

Although very slight bitumen solubility helps to prevent pitch from coalescing, preferably, dicyandiamide solution will not connect It is close to be used at a temperature of being rounded particle boil.The concentration of particle in the solution should be preferably lower (such as in 0.5-2 weight % model In enclosing, such as 1%).If fruit granule is too dense in the solution, then they have coalescence to be inclined to.

In rounding and cause between agglomeration there is time-temperature relationship, this depends on the pitch being rounded or polymer Concrete property.It is preferred that particle is dispersed with agitation, because particle may settle or reach the surface of liquid in the process And reunite.

Addition, which is not fusible material (such as carbon black, rework, graphite and other very small particles), can help to Prevent precursor reunion when melting and being rounded.This method can produce following carbon, and the carbon includes having degree of graphitization ratio The shell structure on the high surface of core or the internal non-graphite shell for having more graphitized areas.This method is likely to provide unique urge Change property, but this has not proved out

Already have accounted for many solvents.For price and environment influence, water certainly optimal solvent.

However, water is not applicable other than the spheroidization of 80 DEG C or the particle of more low melting point.Once solvent close to its Boiling point, surface nature just change, and tendency of reuniting increases.When using water, surfactant such as Tween 80, tween 20, Triton X-100 or polysorbate80 are helpful.What is be particularly helpful is using organic silicon surfactant, such as Silwet 77。

For the pitch of higher melt, it has therefore proved that the use of glycerol is successful.Its is water-soluble, and can be easily It washes off.Since it is with high viscosity, particle will not be as reuniting in water.In general, at lower than 40 DEG C to 5 DEG C of fusing point Use glycerol.If we are heated to that reaction must be terminated rapidly lower than 3-5 DEG C of fusing point, because it is more problematic to reunite.It can lead to It crosses and adds cold solvent with fast cooling and terminate pitch particle hardening to realize.Once cooling pitch cools down, i.e., It sieve can be used to be filtered, and most of glycerol reused.

It is undesirable that solvent distillation and reusing, then the particle for being loaded with glycerol can be washed.

Other polyalcohols, acid and alcohol can be added into glycerol initially to wash away most of glycerol, and at a lower temperature Vacuum distillation is fallen.Alternatively, the thorough washed product of water can be used.

The preferred solvent to work includes but is not limited to following chemical classes: -ol, organic acid, polyalcohol, water, glycerol, two Property ionic compound, amine, polymeric liquid (including comprising such as xanthan gum, algin, the thickener of guar gum, surfactant, Increase the liquid of product agent etc.).

Every kind of pitch and precursor are different.It is critical to choose the solvent of pitch selected by unobvious dissolution.Secondly solvent is answered Some viscosity, and boiling point should be at least 20 DEG C higher than the temperature of rounding, and preferably 40 DEG C high.If there is some reunions, In then contour shear mixer can crushing agglomerates, so as to separate round pitch particle again.However, if crossing high temperature Under degree too long by reactant heating, then pitch will reunite completely, and must carry out refuse and stone roller as rework Mill.

Prepare have specified particle size and for circular particle alternative be related to injection fusing carbon precursor or carbon precursor exist Solution in solvent, the particle can be by refuse/recycling if granularity is inappropriate.

Ejector dryer and fluidized bed or tower can be used to prepare the injection formed particulate with appropriate granularity.Herein In embodiment, pitch or other fusible precursors are prepared and by nozzle/mold ejector.Before asperity contact, they are all Solidify and is rounded into particle.These particles are classified with as the particulate species by milling and being rounded according to granularity, to move Except too big or too small particle.The appropriate particle of granularity will be stabilized.Particle other than required range will pass through refuse It is recovered to eliminate waste material.It can avoid step of individually milling by this approach.

It stabilizesBe defined as following technique for purposes of this application: thus pitch or other precursors can be changed by chemistry Property, so that it will not refuse in carbonization.Some technical staff of this field are referred to as thermosetting property.

The purpose of this step is well-known, and is implemented in the preparation of pitch fibers before carbonization is at carbon 's.The tendency of this lockable formation graphite.

The oxygen being attached in precursor granules or other substituent groups inhibit fusing, and make it possible to heat stabilized hydrocarbon And it is converted to carbon.

During this step, temperature is controlled, so that not melting before particle is oxidized and is injected.It as we all know there are perhaps More compounds can accomplish this point, including peroxide, persulfate, pyrosulfate, perchlorate, sulfate, sulfurous acid Salt, sulphur, disulfate, bisulfites, sulfamate and nitrate.Especially welcome technique includes using nitric acid, sulphur Acid, air, hydrogen peroxide, nitrous oxide and ozone, this is because their cost is low.

In order to stablize the circular granular compared with low melting point, it is proposed that carry out nitric acid oxidation, then carry out air oxidation.However, right For the precursor of higher melt, air or nitric acid are usually preferred.

If this step is not completed sufficiently, product will stick together and condense into agglomerate.If this step is made suitable If, product will never cling or only very slight cling.United States Patent (USP) 4275051 and many other reference texts It offers and explains this technique.

When being stabilized with air, stirs or ensure that air uniformly in contact with all parts of particle is useful. Otherwise, it is impossible to enough generation prerequisite oxidations.This may cause particle-bonded ceramic or condensation.

Therefore, common air or ozone stable method include being stirred by rolling, fluidizing injection or lift gas column Dynamic particle.Preferred method is slowly to stir, such as roller heater or rotary calcining furnace.

For air oxidation, temperature should be preferably 170 DEG C to 250 DEG C.For example, this can be accomplished by the following way: will Temperature was maintained at 170 DEG C up to 40 hours；Or temperature is increased to 250 DEG C from 170 DEG C with 10 DEG C/h.

When using nitric acid oxidation, concentration and time depend on precursor pitch or other fusible precursors.Time and temperature It can change, but room temperature or be preferred lower than the oxidizing temperature of room temperature.In order to be reduced to degree of oxidation to subsequent carbonization It is crucial degree for step, lower concentration of nitric acid is preferred, and the time is shorter.More preferably in the temperature of room temperature Under, using the nitric acid solution of 10-30%, continue 5-15 minutes, this depends on the characteristic of original asphalt.Obtain in this way for lithium from The lower preferred product of the surface area of sub- battery applications.For the catalytic applications for needing high surface area, using than lithium Ion battery applies higher concentration of nitric acid, longer time and higher temperature.Certainly, addition catalyst can reduce realization phase With the level of nitric acid needed for degree of oxidation.These catalyst are well-known in the art, and may include strong lewis acid The acid of (Lewis acid) or sulfuric acid, hydrochloric acid, phosphoric acid, sulfonic acid etc..

In some cases, it can be carbonized in same container after oxidation.It is hydrated during stabilisation in wherein carbon In other situations, it is generally desirable to it is before carbonization that product is dry, or remove at least most of moisture.Multistage heating drying can Complete dry and carburising step in an equipment.Required stabilisation property and degree will be different because of precursor.

Multiple stabilization steps may be needed to ensure that particle will not reunite during further processing.This might mean that can It can need to make low melting point Bituminous stabilized by two different methods, such as progress nitric acid oxidation, then carry out air oxidation. The present invention covers for converting the precursor to the anti-fusing during carburising step that be any well-known or developed in the future The chemical substance of grain.

Carbonization.Carbonization requires heat to the temperature for converting carbon precursor in carbon.Usually this includes being heated to 600 DEG C and 1200 Temperature between DEG C, the temperature depend on required property.In order to minimize surface area, if you do not need to individually graphitization step Suddenly, then up to 1700 DEG C may be required heat to.

During this technique, the seen temperature during stabilisation can be rapidly heated the material to.In general, can will produce Object is put into saggar or is purged with nitrogen to prevent that air oxidation occurs during carbonization.Heating rate will greatly influence Density and surface area.It, will be using 20 DEG C/h of ramp rate between 170 DEG C and 400 DEG C for general aspects.It is right For the lesser particle of surface area, 5-10 DEG C/h of slower ramp rate is advantageous.And surface area smaller for density For biggish product, 20-50 DEG C/h of ramp rate can be used.Once usually can be used 50 DEG C/h to 400 DEG C Ramp rate, until 600-1300 DEG C.For many applications, the powder of carbonization is sufficient.

Can mill the particle of excessive (such as passing through reunion) or too small (such as passing through mechanical damage) after being carbonized, and be made It is incorporated into pitch for rework.

Can directly it make in same step such as natural polymer as made of cellulose powder and thermosetting plastics Some particles are rounded and are carbonized.It in the case of cellulose, can be by mineral oil, glycerol, silicone oil and other higher boilings It directly heats in solvent/solution and they is carbonized with agitation.If this is completed with agitation, institute will be made simultaneously Particle is obtained to be rounded and be carbonized.

Step after carbonization.Once carbon dust has been made, then many possible modifications can be carried out to introduce knot into carbon material Structure and functionality.For some catalysis uses, wettable material is so that product is densified or coated on product. These coatings may include such as pitch and other materials, polymer, sugar, ester etc..

Another technique that can be applied to carbon is activation, and the hole and region of catalytic activity can be introduced by the activation.Normally Priming reaction is completed using air, carbon dioxide, steam, potassium hydroxide and sodium hydroxide.Many chemical substances can lead to Activation, including air inadequately enter product.

In addition, halogen can be used to purify or washed with acid and other chemical substances come purified carbon.

Optional graphitization/purifying.Graphitization has a significant impact to the numerous characteristics of powder.Most of all, graphitization It can be by the surface area of these powder from 2-500m²/ g drops below 1m²/g.This heating steps can also increase compacted density, although Its tap density that usually will not greatly influence circular granular.

In addition, most first time cycle capacity loss would generally be eliminated by being heated to graphitization temperature.These characteristics pair In they for the purposes in some applications of such as anode of lithium ion battery it is extremely important.This step can also reduce pollution Object, because many elements will distil during graphitization at a temperature of up to 3200 DEG C.Specific highest graphitization temperature can Property is greatly influenced, but the cost of product may be will increase.

Embodiment