Carbon black fluffy

Black Pigments. The only black pigment used to an appreciable extent in inks is carbon black It is used in newsprinting, pubHcation, commercial and packaging printing therefore, in large quantities. Black pigments ate offered in fluffy or beaded forms and in a variety of particle sizes and physical properties. 

Carbon black is made by the vapour-phase incomplete pyrolysis of hydrocarbons to produce a fluffy fine powder. Worldwide, about 7 million tons a year are produced. It is used as a reinforcing agent in rubber products such as tyres (20-300 nm), as a black pigment (<20 nm) in printing inks, paints, and plastics, in photocopier toner, and in electrodes for batteries and brushes in motors. 

The carbon black industry takes extreme efforts to confine product during all stages of manufacture (45). Highly efficient bag filters are used to collect the product. After collection the fluffy carbon black is densified and pelletized to minimize dusting problems during shipping and use. 

The fluffy carbon black coming out of the filter is pneumatically conveyed into a first storage tank. Small amounts of impurities ( grit, e.g., iron, rust, or coke particles) are either removed by magnets and classifiers or milled to an appropriate consistency. 

The oil furnace process is the most common method of production today and is the source of over 95% of the total output of carbon black globally. In this process, a heavy aromatic fraction of petroleum distillate is atomized and sprayed into a furnace preheated to 1200-1900°C. The feedstock vaporizes and decomposes to form carbon black and combustion gases that are immediately cooled with a series of water sprays and heat exchangers to terminate the carbon black reaction and cool the carbon black product stream. The carbon black is separated from the combustion gases in bag filters and is conveyed for further densification either in pelletization processes or in agitator tanks (from which powdered, fluffy black is collected). 

As formed, carbon black is a fluffy powder possessing low density. The densification process involves the removal of occluded air by agitation and followed by dry or wet process pelletization. In both the dry and wet pelletization process, nearly spherical pellets or beads will form that are typically composed of >99% carbon black and trace impurities such as sulfur. Thus, carbon black is sold as a low density powder or as a pelleted form in pigmenting and other end uses. The choice of a fluffy or pelleted carbon black for dispersion in a given system depends upon the dispersion and handling equipment and end use. For example, pelleted carbon blacks are used most frequently in production of black masterbatch carbon black powders are typically used to tint chromatic compounds. 

Carbon black is produced by the partial combustion or thermal decomposition of hydrocarbons. Several methods are used, including the furnace black, thermal black, lamp black and acetylene black processes. The furnace black process is the most common. In this process, natural gas (or another fuel) is burned to form a hot gas stream that is directed into a timnel. An aromatic oil is sprayed in and the black forms as the gas moves down the tunnel. The reaction is quenched with the addition of water, and the product is collected as a low density powder (fluffy black) or is further processed into millimeter sized peUets. 

The term pyrolytic carbon can be applied to carbon filaments, carbon blacks, and carbon films, as well as to the more massive deposits which are the subject of this section. Pyrocarbon materials, made by chemical vapor deposition (CVD), vary in density, properties, and structure as much as the bulk materials discussed in 17.3.4.1. A heated hydrocarbon gas decomposes into an entire series of molecular species with a wide spectrum of carbon contents and molecular weights Within this pyrolyzing atmosphere, droplets form that pyrolyze and condense on a nearby surface, or large carbonaceous complexes may condense directly on the surface of the chamber. The former condition produces a fluffy, sooty, soft carbon, not far removed from carbon black, while the latter produces a hard solid carbon. The second of these materials is of primary interest here. The structure of the carbon produced by the CVD process has been shown to depend on the type of hydrocabon and its concentration, the pyrolysis temperature, the contact time, and the geometry of the pyrolyzing chamber. Of these, the pyrolysis temperature is perhaps the most important, but it is the nature of the chamber that conveniently divides the carbons produced into two distinct types. 

The degree of dispersion and j etness achieved when grinding carbon black depends on the wetting properties of the dispersing material and to some degree on the filler form. For instance, pelletized earbon blaek is easier to disperse than a fluffy type... 

Monarch . [Cabot] Fluffy carbon black for plastics, coatings. 

Chem. Descrip. Carbon black CAS 1333-86-4 EINECS/ELINCS 215-609-9 Uses Colorant, UV stabilizer for plastics and coatings Features Med. jetness exc. elec, conductivity Properties Fluffy 18 nm particle size dens. 9 Ib/ft surf, area 200 mVg pH 6-8 1.5% volatiles Monarch 800 [Cabot/Special Blacks]... 

Properties Black, fluffy powder. Mp >180°C with decomposition pK unknown but pH of saturated solution is 5.0 log 0.83 (calculated) log -1.00 (calculated) S soluble in acetone, acetonitrile, benzene, carbon tetrachloride, chloroform, ethanol, methanol, -propanol, pyridine, toluene, xylene and many other organic solvents S 120-130 g/L at 20°C (pH of solution = 5.0) vp negligible at 20-25°C. 

Elftex, Fluffy furnace carbon black, Cabot Corp., Special Blacks Div. 

The fluffy black from the bag filter is mixed with water, typically in a pin mixer, to form wet granules. These are dried in a rotary dryer, and the dried product is conveyed to bulk storage tanks. For special purposes, dry pelletization in rotary drums is also practiced. Most carbon black is shipped by rail or in bulk trucks. Various semibulk containers are also used including IBC s and large semibulk bags. Some special-purpose blacks are packed in paper or plastic bags. 

Fluffy carbon blacks can be fed and dispersed without problems, whereas pelleted carbon blacks are difficult to feed... 

Carbon black can be produced using several methods, including the lampblack, channel black, thermal black, and acetylene processes. However, the vast majority - over 90% - of today s carbon black is manufactured using the oil furnace process, a highly efficient method that permits rigid control of chemical and physical properties. The oil furnace process yields carbon black in fluffy or low-density powder form. Many grades are subsequently converted to pellets (beads) for ease of handling. 

Pelleted carbon blacks are available in plastic or paper bags, intermediate bulk containers (IBCs) or railcars. Fluffy grades are generally available only in paper bags. 

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