Carbon blacks formation mechanism

Mechanism of Carbon-Black Formation in Relation to Compounded-Rubber Properties... 

Mechanism is generally employed as a word to describe the individual rearrangement of atoms as molecules react to form new compounds and products. The mechanism of carbon black formation is used in this context as it appears in the title of this presentation. 

Progress is achieved through change which is understood. So, in this instance, scientific knowledge must surpass the art, and a knowledge of the Mechanism of Carbon Black Formation in Relation to Compounded Rubber Properties prevails. 

The Mechanism of Carbon Black Formation and the Manufacturing Process... 

There are a great many published reports describing studies of carbon black formation in flames. Many of these deal with gaseous fuels in either pre-mixed flames or diffusion flames. The principal objectives are to develop a better knowledge of combustion through an understanding of the kinetics and mechanism of carbon formation,... 

A thorough familiarity of these works and the theories presented is essential for effective studies of the mechanism of carbon black formation however, a review of these works here is well beyond the scope of this paper. A number of extensive review articles and books are recommended (2, 1 >, L7, Z5, M, 12, 13, 42) <... 

The principal materials being fed into the reactor are air, gas (or fuel), and the feedstock. The materials coming out of the reactor are, of course, combustion gases, carbon black, water, and the nitrogen which comes into the reactor in the air and passes through unchanged. The question we have then is how is the feedstock converted to carbon black What are the reactions that occur, where do they occur, and under what variables, what are the reactor rates, and what are the mechanisms of carbon black formation What are the key variables in the system relative to controlling particle size, surface area, and structure ... 

This latter conclusion is in agreement with other published reports on the mechanism of carbon black formation. For example, Tesner (42, 43, 44, 45) is most well known for his theories of nucleation and growth of carbon particles. In a communication with Gaydon and Wolfhard (15), Tesner revealed that carbon particles in contact with carbon monoxide in a furnace show no growth whatsoever at any temperature. A mechanism reporting nucleation followed by growth in the carbon black reaction was recently reported by Dahmen (10) however, none of the experimental techniques nor data were presented. 

Although the mechanisms of carbon black formation and particle growth an not entirely clear, it now seems likely that polyaromatic hydrocarbons are the important precursors (Lahaye and Ehrburger-Dolle, 1993). However, it appear only about 10% of the final mass is deposited during the initial stages of pa nucleation. Most of the carbon yield is due to particle growth and this is prol dependent on both particle-particle and particle-vapour interactions, with acet and other unsaturated hydrocarbons involved in the surface reactions. 

Wersborg, B. L., Physical Mechanisms of Carbon Black Formation in... 

The Formation of Filamentous Carbon, R. T. K. Baker and P. S. Harris Mechanisms of Carbon Black Formation, J. Lahaye and G. Prado... 

Although not yet fully elucidated, the carbon black formation seems to follow a basic formation mechanism consisting of different steps for the carbon black growth, which essentially applies for all types of manufacturing processes ... 

Lewis, J.E. Mechanism of carbon-black formation in relation to compounded-rubber properties In Bacha, J.D., Newman, J.W., White, J.L., Ed. Petroleum Derived Carbons, ACS Symposium, Ser.303, 269 (1986)... 

R. C. Bansal, J-B. Donnet, Mechanism of Carbon Black Formation , in Carbon Black. Sci. Technol. (Eds. J-B. Donnet, R. C. Bansal, M-J. Wang), Marcel Dekker, New York, Basel, Hong Kong (1993)... 

J. Lahaye, F. Ehrburger-Dolle, Mechanism of Carbon Black Formation. Correlation with the Morphology of Aggregates , in Proceedings 2nd Int. Conf on Carbon Black, Mulhouse (F), 27-30. September 1993, pp. 11-23... 

Bansal, R.C. and Donnet, J.-B. (1993) Mechanism of carbon black formation. Chapter 2, in Carbon Black Science and Technology, 2nd edn (eds J.-B. Donnet, R.C. Bansal and M.-J. Wang), Marcel Dekker, Inc., New York. 

Mechanisms of carbon black formation must account for the experimental observations of the unique morphology and microstructure of carbon black. These include the presence of nodules, or particles, multiple growth centers within some nodules, the fusion of nodules into large aggregates, and the paracrystalline or concentric layer plane structure of the aggregates. It is generally accepted that the mechanism of formation involves a series of stages as follows ... 

G. Heinrich, M. Kliippel. A hypothetical mechanism of carbon black formation based on molecular ballistic deposition. Kautsch. Gummi. Kunstst., 44, 419-423, 1991. 

The formation of carbon black in a candle flame was the subject of a series of lectures in the 1860s by Michael Faraday at the Royal Institution in London (23). Faraday described the nature of the diffusion flame, the products of combustion, the decomposition of the paraffin wax to form hydrogen and carbon, the luminosity of the flame because of incandescent carbon particles, and the destmctive oxidation of the carbon by the air surrounding the flame. Since Faraday s time, many theories have been proposed to account for carbon formation in a diffusion flame, but controversy still exists regarding the mechanism (24). 

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