Pyrolysis parameters

Ericsson I (1985) Influence of pyrolysis parameters on results in pyrolysis-gas chromatography J Anal Appl Pyrolysis 8 73-86... 

Pyrolysis is an ancient method of decomposing solid matter by heating to high temperatures examples are production of metals, coke furnaces, and obtaining of chemicals from coal prior to petroleum. There are many kinds of pyrolysis batch, semi-batch or continuous catalytic or non-catalytic out under vacuum or at atmospheric or high pressure. Its medium may be inert, oxidative or reductive. Heating rate, temperature, and time are important pyrolysis parameters. 

The porous structure and specific surface of activated carbons are determined by precursor type [13] and pyrolysis parameters, i.e. temperature [14] and heating rate jl5.16]. M y papers are dedicated to the synthesis of active carbons based on lignin-cellulose materials of various types [17]. There are empirical dependencies of texture on thermal treatment parameters for caibon materials from various precursors of plant nature [13,14,18]. Models for cellulose fibers pyrolysis are suggested [15). 

Pakdel H Roy C. Lu X. (1996). Effect of Various Pyrolysis Parameters on the Production of Phenols from Biomass. In Developments in Thermochemical Biomass Conversion. ( Ed. by A. V. Bridgwater D.G. B. Boocock), pp.509-522. Blackie Academic Professional, London. 

The temperature dependence of the rate of reactions is particularly Important for the pyrolytic processes. Relation (5) can be used for the understanding of the common choices for the pyrolysis parameters. As an example, we can take the pyrolysis of cellulose [8]. Assuming a kinetics of the first order (pseudo first order), the activation energy in Arrhenius equation was estimated E = 100.7 kJ / mol. The frequency factor was estimated 9.60 10 s These values will lead to the following expression for the weight variation of a cellulose sample during pyrolysis ... 

The temperature dependence of the rate of reactions is particularly important for the pyrolytic processes. Rel. (2.3.5) and (2.3.35a) can be used for the understanding of the common choices for the pyrolysis parameters, their combination leading to ... 

Another advantage of this process is its high flexibility. Indeed, the composition, structure (amorphous or crystalline), microstructure, and properties of the ceramic material can be controlled and adjusted by varying many different parameters such as the composition and architecture of the pre-ceramic polymer, the amount and nature of the filler, the cross-linking step, and the pyrolysis parameters (atmosphere, heating rate, final temperature). Also, nonconventional heating systems such as laser or microwave heating or even athermal conversion processes like ion bombardment can be efficiently used. 

K. M. Steel, W.J. Koros, An investigation of the effects of pyrolysis parameters on gas separation properties of carbon materials. Carbon 2005, 43 (9), 1843-1856. 

In principle, one can determine which pyrolysis parameters are important and contribnte most significantly to the stmctural changes of the material. In that case, it wonld be possible to predict the trends of transport properties for a given carbon material more effectively. Recently, the precnrsors were pyrolyzed in a step-by-step fashion (i.e. after reaching a certain temperatnre, holding the membrane at that temperature for a period of time and then heating it again) imtil the final pyrolysis temperature is reached [34, 44, 51, 92, 93]. 

Beis, S. H., Onay, O., Kockar, O. M. Fixed-bed pyrolysis of safflower seed influence of pyrolysis parameters on product yields and compositions. Renew Energ 2002, 26, 21-32. 

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