Carbon pyrolysis

Carbons may have closed and open pores with a large variety of dimensions from a few Angstroms to several microns. In terms of structure, the pores in active carbons are divided into three basic classes [66, 69] macropores, transitional pores, and micropores. Pores are formed during the production of carbon (pyrolysis of its precursors), or can be formed by other means such as oxidation by 02, air, C02, or H20 [66]. According to Dubinin s... 

Carbon Pyrolysis High strength High modulus Low density Low oxidation resistance Medium cost Reinforced plastics Carbon-carbon High-temp insulation... 

Thermal Decomposition 1500 CI Carbonization Pyrolysis Wood distillation Destructive distillation Gasification... 

A number of terms are used for the thermal decomposition of wood and generally refer to similar processing methods carbonization, pyrolysis, gasification, wood distillation, destructive distillation, and dry distillation. All result in the thermal breakdown of the wood polymers to smaller molecules in quantities dependent on reaction conditions. The hydrogen content of the gas increases with increasing temperature of pyrolysis. The wood gas has a fuel value of 300 BTU/ft3. 

Heteroatoms with impaired p-electrons (N, O, S) are partly removed from the carbonized pyrolysis products at temperatures above 600 °C. This process of heteroatom removal from the carbon skeleton may continue up to temperatures of 1300 to 1700 °C. 

Oberlin, A., ViUey, M., and Combaz, A. (1980). Influence of elemental composition on carbonization. Pyrolysis of kerosene shale and kuckersite. Carbon, 18, 347-53. 

Selective dkylation of benzene and alkylbenzenes over various zeolites has been studied extensively since the 1960 s, as summarized in many reports [Venuto and Landis, 1968 Yashima et al., 1970 Kaeding et al., 1981 Haag, 1984 Chen and Garwood, 1986 Yashima, 1988 Dwyer, 1991 Bhat et al., 1992 Chen et al., 1996 Xu et al., 1996]. However, until recently, little attention has been paid to selective alkylation of two-ring aromatics such as naphthalene and biphenyl. Naphthalene and its derivatives are rich in liquids derived from coals via carbonization, pyrolysis and liquefaction. Due to the need for monomers for making the advanced polymer materials shown in Scheme I, (3-selective naphthalene alkylation has become an important subject. In particular, 2,6-dialkyl substituted naphthalene (2,6-DAN) is needed now for making the monomers for PEN, PBN and LCPs shown in Scheme 1. 

In general terms, the behavior of coal during combustion, carbonization, pyrolysis, gasification, and direct conversion to liquids depends on the type and amount of the macerals present (Fryer et al., 1975 Falcon, 1978 Stach et al., 1982 Bend et al., 1991 Derbyshire, 1991 Kalkreuth et al., 1991 Murchison, 1991 Gagarin and Krichko, 1992 Sen, 1992 Speight, 2005,... 

Scherson, D. A.A. Tanaka, S.L. Gupta, D. Tryk, C. Fierro, R. Holze, and E.B. Yeager (1986). Transition metal macrocycles supported on high area carbon Pyrolysis-mass spectrometry studies. Electrochim. Acta 31, 1247-1258. 

In industry, activated carbons are essentially produced by carbonization (pyrolysis at temperatures up to 900°C under neutral atmosphere) of various precursors (lignocellulosic, polymers, anthracites,. ..), followed by physical and chemical activation [1], Physical activation is generally realized around 900°C through partial gasification of carbon, using CO2 or steam, according to Eqs. 12.1 and 12.2 ... 

Scherson DA, Tanaka A, Gupta SL, Tryk D, Fierro C, Holze R, Yeager EB (1986) Transition metal macrocycles supported on high area carbon pyrolysis-mass spectrometry studies. Electrochim Acta 31 1247-1258... 

A novel approach to the synthesis of glycopyranosides has involved the pyrolysis of acylated glycopyranosyl carbonates. Pyrolysis of (27 R = Me or Ph,... 

The representative carbon precursor is the phenol formaldehyde resin, polyacrylonitrile, pitch, coke, coconut shell, wood, etc. In most cases, these precursors are activated after carbonizing (pyrolysis in inert gas). The activation process for preparing the activated carbons is classified as gas activation (physical activation) and chemical activation. These activation characteristics are summarized in Table 1. In the former, the starting carbon materials are gasified using steam or carbon dioxide gas at... 

The materials reviewed in this chapter form another distinctive group of carbon materials the vitreous carbons. Like molded graphite, vitreous (glassy)carbon is processed by the carbonization (pyrolysis) of an organic precursor. Unlike most molded graphites, it does not graphitize readily and has characteristics and properties that are essentially isotropic. The difference between these two classes of materials stems from different precursor materials. 

Quantum-Chemical Interpretation OF Carbon Pyrolysis Kinetics... 

Key words active complex, carbons, pyrolysis, direct and back reactions. 

The aim of this paper is the calculation of kinetic parameters for elementary reactions of carbons and some substituents of carbons pyrolysis by PM3 method [7],... 

Table 1. Values of kinetic and thermodynamic parameters of carbons pyrolysis (900 K)...

Table 2. Values activation entropy and pre-exponents for reaction of carbon pyrolysis (900K)...

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