Carbon black, method for the production f carbon black or other flame aerosols, and device for carrying out said method

Abstract

A method for producing carbon black or other flame aerosols, comprising the following steps: the heat is removed from the flame by dissipation and/or radiation; a thin gas boundary layer is formed; the flow formed by the flame and the gas boundary layer is accelerated or expanded; the obtained aerosol is withdrawn; and the cooling surface is cleaned. The invention further relates to a device for carrying out such a method and a black carbon having a maximum pH value of 6.0, a maximum ignition residue of 0.1 percent, and a maximum 5 μm screening refuse of 200 ppm. The inventive black carbon can be used in rubber, plastic, bitumen, concrete, and other construction materials.

1 - 24 . (canceled)  
     
     
         25 . A method for the production of carbon black or other flame aerosols comprising: 
 a) removing heat from a flame by thermal conduction and/or radiation, the heat being released at a cooling surface which is a solid, cold surface or a liquid surface;    b) forming a thin gas boundary layer between the flame and the cooling surface, in order to prevent the accumulation of aerosol particles on the cooling surface;    c) accelerating or expanding flow formed by the flame and the boundary layer, in order to keep the flow laminar and to achieve as thin a boundary layer as possible; and    d) withdrawing the aerosol formed from the vicinity of the cooling surface.    
     
     
         26 . The method according to  claim 25 , further comprising cleaning the cooling surface.  
     
     
         27 . The method according to  claim 25 , wherein the thin gas boundary layer is air.  
     
     
         28 . The method as claimed in  claim 25 , wherein the boundary layer is produced by feeding a gas stream between the flame and the cooling surface.  
     
     
         29 . The method as claimed in  claim 25 , wherein the boundary layer is guided into the region of the flame by movement of the cooling surface.  
     
     
         30 . The method as claimed in  claim 28 , wherein the boundary layer is guided into the region of the flame by movement of the cooling surface.  
     
     
         31 . The method as claimed in  claim 25 , wherein the boundary layer is introduced between the flame and the cooling surface by a deflector plate.  
     
     
         32 . The method as claimed in  claim 25 , wherein the boundary layer is produced by a flow of a gas or vapor through the cooling surface having openings or pores.  
     
     
         33 . The method as claimed in  claim 25 , wherein the boundary layer is produced by the vaporization of a liquid on the cooling surface.  
     
     
         34 . The method as claimed in  claim 25 , wherein the flame is guided between two cooling surfaces having two boundary layers.  
     
     
         35 . The method as claimed in  claim 25 , wherein the flame is cooled in a convergent gap or convergent channel having cooling surfaces and having boundary layers.  
     
     
         36 . The method as claimed in  claim 25 , wherein the flame is cooled in a convergent gap between two rotating rolls having cooling surfaces and having boundary layers.  
     
     
         37 . The method as claimed in  claim 25 , wherein the aerosol-containing flow layer is removed from the cooling surface by a nozzle through which gas flows.  
     
     
         38 . The method as claimed in  claim 34 , wherein the flow velocity at the narrowest point of the convergent gap is chosen to be substantially higher than the exit velocity of the flame from the burner.  
     
     
         39 . The method as claimed in  claim 34 , wherein the flow velocity at the narrowest point of the convergent gap is measured and regulated by a pressure difference present at the gap.  
     
     
         40 . The method as claimed in  claim 34 , wherein the cooling surface is a metal surface which is cooled from its back by water.  
     
     
         41 . A device for carrying out the method as claimed in  claim 25 , comprising a flame generator, a cooling surface against which the flame produced can be directed, and means for producing a gaseous boundary layer between said surface and said flame.  
     
     
         42 . The device as claimed in  claim 41 , further comprising a deflector plate arranged between the flame and the cooling surface.  
     
     
         43 . The device as claimed in  claim 41 , wherein the cooling surface has openings or pores through which cooling gas can pass.  
     
     
         44 . The device as claimed in  claim 41 , wherein the cooling surface is formed by two rotating rolls.  
     
     
         45 . The device as claimed in  claim 41 , wherein the cooling surface is a convergent gap comprising a revolving belt which is guided over a roll in the region of the gap and which passes through a liquid bath for cleaning and cooling.  
     
     
         46 . The device as claimed in  claim 45 , wherein the belt is porous and is impregnated with a liquid.  
     
     
         47 . The device as claimed in  claim 45 , wherein the belt is a porous textile and is impregnated with a liquid.  
     
     
         48 . The device as claimed in  claim 45 , wherein the gap width at the narrowest point of the convergent gap can be adjusted in the range from 0.5 to 10 mm.  
     
     
         49 . The device as claimed in  claim 41 , wherein the flame has a base and the distance between the base of the flame and the cooling surface can be adjusted.  
     
     
         50 . The device as claimed in  claim 41 , wherein the flame has a base and the cooling surface has a convergent gap and the distance between the base of the flame and the narrowest point of the convergent gap can be adjusted.  
     
     
         51 . An unclassified, untreated carbon black, having a pH less than or equal to 6.0, a residue on ignition less than or equal to 0.1% and the 5 μm sieve residue less than or equal to 200 ppm.  
     
     
         52 . A composition of matter comprising the carbon black as claimed in  claim 51  and a member selected from the group consisting of rubber, plastic, printing ink, ink, inkjet ink, toner, a finish, paint, paper, bitumen, concrete, other construction materials and mixtures thereof.