Thermal blacks

Thermal asphalt Thermal blacks Thermal bonding Thermal chlorination Thermal coatings Thermal comfort Thermal conductivity... 

When natural gas is used as a feedstock to produce thermal blacks, the reaction is endothermic. In order to maintain the reaction, the reactor has to be kept at about 1300°C. When acetylene is used as the feedstock to produce acetylene blacks, the reaction is exothermic, and the reaction can be mn at a temperature between 800 and 1000°C. 

The production process or the feedstock is sometimes reflected ia the name of the product such as lamp black, acetylene black, bone black, furnace black, or thermal black. The reason for the variety of processes used to produce carbon blacks is that there exists a unique link between the manufactuting process and the performance features of carbon black. 

Channel blacks such as the old EPC and MPC grades are acidic to neutral and can vary from having Httie effect to having a slight retardation in cure rate. The pH-neutral large-particle size MT thermal black generally has Httie effect on cure rate. 

A number of processes have been used to produce carbon black including the oil-furnace, impingement (channel), lampblack, and the thermal decomposition of natural gas and acetjiene (3). These processes produce different grades of carbon and are referred to by the process by which they are made, eg, oil-furnace black, lampblack, thermal black, acetylene black, and channel-type impingement black. A small amount of by-product carbon from the manufacture of synthesis gas from Hquid hydrocarbons has found appHcations in electrically conductive compositions. The different grades from the various processes have certain unique characteristics, but it is now possible to produce reasonable approximations of most of these grades by the od-fumace process. Since over 95% of the total output of carbon black is produced by the od-fumace process, this article emphasizes this process. 

Table 11 Hsts the types and appHcations of special pigment-grade carbon blacks. Included in this Hst are thermal black and lampblack. Over 40 special black grades have been developed based on the furnace process having a broad range of surface areas, from 20 m /g to over 1500 m /g. The lower surface area products are used in printing inks and tinting. The high area, more expensive products find use in high color enamels and lacquers.

Includes one thermal black plant (capacity, 25,000 t). Estimate. 

Source From Blake, J.T. and Bruce, P.L., Ind. Eng. Chem., 33, 1198, 1941. P-33 is a fine thermal black, ASTM nomenclature N880. 

FIGURE 26.44 Abrasion loss as function of pressure for four different compounds. A SBR + 50 HAF black, B NR + 50 HAF black, C NR + 50 thermal black, D NR + 50 activated CaCOs. (From Schallamach, A. and Grosch, K.A., The Mechanics of Pneumatic Tires, S.K. Clark (ed.), The US Department of Transportation, National Highway Safety Administration, Washington DV, p. 407.)... 

Abbreviation for Fine Thermal Carbon Black. The only form of thermal black now in common use is Medium Thermal (MT) black. See Thermal Black. 

Abbreviation for medium thermal carbon black. See Thermal Black. 

Breaking down of a chemical substance by means of heat. See Cracking and Thermal Black. Thermal Diffusivity... 

Carbon blacks are principally made by the chemical decomposition of natural gas or oil. Two classes predominate the furnace blacks (95% of black usage) which are active, and thermal blacks (5% of usage) which are inactive. There are a substantial number of blacks for special applications such as electrically conducting and printing ink blacks. The latter are of too fine a particle size for rubber use. The nomenclature used for carbon blacks includes the ASTM designation and the industry type as illustrated in the next table. 

The surface area of blacks ranges from 20 m2/cm3 (N990 - Medium thermal black) to 225 m2/cm3 (N110 - Super abrasion furnace black). 

Channel Black Also called Gas Black. One of the processes used to make carbon black the others are the Acetylene Black, Fumace Black, Thermal Black, and Thermatomic processes. In the Channel Black process, natural gas was incompletely burnt in small flames, which impinged on cooled channel irons that were continuously moved and scraped. Invented by L. J. McNutt in 1892 and commercialized that year in Gallagher, PA. The last United States plant was closed in 1976. 

Furnace Black One of the three principal processes used for making carbon black the others being the Thermal Black and the Channel Black processes. In the Furnace Black process, aromatic fuel oils and residues are injected into a high velocity stream of combustion gases from the complete burning of an auxiliary fuel with an excess of air. Some of the feedstock is burned, but most of it is cracked to yield carbon black and hydrogen. The products are quenched with water. 

Thermal Black One of the processes used to make carbon black. The feedstock is usually natural gas. The gas is pyrolyzed in one of a pair of refractory reactors which has been preheated by burning part of the feed and hydrogen from the process. When the temperature has fallen, the functions of the reactors are interchanged. 

Medium thermal blacks, 4 765t Medium volatile bituminous coal rank and heating values, 6 726t vitrinite reflectance limits and ASTM coal rank classes, 6 708t... 

Thermal blacks, 4 762, 798t manufacture, 4 785-786 Thermal bonding, 17 475-476,... 

Both types of surface oxides are found on technical products. Rubber grade carbon blacks are produced in different processes. Channel blacks are made by cooling a flame on iron plates, the so-called channels. The resulting carbon blacks are acidic in character because an excess of air is present (25). In the production of furnace blacks, the fuel, mostly oil or natural gas, is burned with a limited supply of air. Thermal blacks are obtained by thermal cracking of the gas, which sometimes is diluted with hydrogen. In consequence, both types show weakly basic reaction in aqueous suspension. 

Synonyms Carbon activated carbon acetylene carbon decolorizing carbon actibon channel black furnace black thermal black gas black lamp black ultracarbon... 

This includes furnace black, colloidal black, thermal black, channel black, and acetylene black. 

Thermal black Soft carbon black formed by the decomposition of natural gas (e.g., MT, medium thermal black). It has little stiffening effect, but imparts toughness, resilience, good resistance to tearing, and fair abrasion resistance. 

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