Thermal decomposition of organic

Diminished alkalinity, attributable to thermal decomposition of organic matter to acidic compounds... 

Impairment of steam purity, attributable to thermal decomposition of organic matter to volatile compounds this is especially important where steam is used directly in processing food, pharmaceuticals, or beverages... 

Soil ammonium increases through thermal decomposition of organic N... 

The products of thermal decomposition of organic-mineral fertiliser mixtures were studied by IR spectroscopy, and implications for fire and explosion hazards considered. 

Partially graphitized cokes produced by means of thermal decomposition of organic raw materials, polymers and graphitized carbon fibers show a good performance [1,2,6-17]. The properties of carbon materials are often improved due to large amounts of dopants (H, O, S, N, P, Si, etc.) [9,18],... 

In any mechanistic study the proposed mechanism must fit the observed kinetics, and clues as to likely fits could help eliminate unnecessary trial and error analyses. In 1934 Rice and Herzfeld proposed a set of mechanisms from which systematic rules were inferred relating the observed order to the type of initiation and termination steps. These mechanisms are highly stylized, but even today they often form the basis for the interpretation of the thermal decomposition of organic molecules, though extra steps often have to be added. They demonstrate how only a small change in mechanism will alter the kinetic features in a systematic way. 

The possible extent to which free radical chains may account for the thermal decomposition of organic molecules in the gas phase was first emphasized by Rice and Herzfeld.26 They gave three examples showing how all the known facts in the decomposition of acetone, acetaldehyde and ethane could be explained by chain reactions involving free radicals. Their calculations showed that the first order character of the reaction could be maintained under proper conditions and they estimated reaction rates and temperature coefficients in agreement with the facts. 

Tammann and Oelsen, Z. anorg. Chem., 1927, 172, 407 many metals (copper, iron, tin, aluminium) have characteristic smells, at least when handled (when the perspiration of the skin may have some action). The smell of stones on attrition, noticed by Boyle (see Partington, Nature, 1921, 106, 631), is probably due to thermal decomposition of organic matter. 

Carbonaceous materials (CMs) are sometimes also named polymeric carbons. They are mostly prepared by thermal decomposition of organic precursors. One strategy is pyrolysis of gaseous or vaporized hydrocarbons at the surface of heated substrates, a second is heating (pyrolysis) of natural or synthetic polymers, both in an inert atmosphere. The latter is of special interest, and according to Miyabayashi et al. [374], precursors such as condensed polycyclic hydrocarbons, polymeric heterocyclic compounds, phenol-formaldehyde resins, polyacrylonitrile or polyphenylene are heated to 300-3000 °C for 0.15-20 h. Sometimes, a temperature/time profile is run. The temperature range must be divided into two domains, namely... 

All those results are concordant with other found in literature [6, 7] where the CO is the majority product fi-om the carbonate decon osition in presence of C. Up to 650 C CO and C02 come from thermal decomposition of organic matter and from this temperature the inorganic decomposition starts mainly carbonate decomposition. As these reactions are endothermic they are tfacrmodynamically favoured a higher temperatures. So, as ten erature increases both peaks, CO and CO2, are greater, mainly the CO ones. 

Pyrolysis (or devolatilisation) is a thermal decomposition of organic matter in an inert atmosphere. In the gasification or partial gasification oxidation medium is added to the process. This oxidation medium usually is air or oxygen. Pyrolysis is also the first step in combustion and gasification. 

Technically speaking, gasification is the controlled thermal decomposition of organic material, producing a gaseous fuel and an inert solid ash residue. This controlled thermal processing can be accomplished through two types of reactions ... 

Also, elimination reactions (mostly, free radical elimination Er) are widespread in thermal decomposition of organic residue on the modified oxides surface. Degradation of organosilicon cover of modified silica surface at high temperatures presents an example of such transformation [65]. 

The Arrhenius plot gave activation energy of 29 kJ mol for the initial decay parts. Activation energy for steady-state luminescence of cellulose was obtained to be 50 kJ mof. Those value are significantly low compared to the reported activation energies for the thermal decomposition of organic hydroperoxides which is ranging from 96 kJ mof to 116 kJ mof. ... 

The explanation of this inherent flame retardancy is the high char yield generated by the thermal decomposition of organic structures containing triazinic rings. It is well known that melamine is used itself as a flame retardant additive in flexible PU foams. 

The thermal decomposition of organic compounds can also be employed to generate small carbon clusters or atoms. The borderline with chemical vapor deposition (CVD) as presented in the next section is not really fix. In both cases, the method is based on the thermal decomposition of organic precursors. Processes both with and without catalyst have been reported. Contrary to the chemical vapor deposition, however, the catalyst (if applied) is not coated onto a substrate, but the substance or a precursor is added directly to the starting material ( floating catalyst ). The resulting mixture is then introduced into the reactor either in solid or in liquid state by a gas stream. From this point of view the HiPCo-process could also be considered a pyrolytic preparation of SWNT, but due to its importance it is usually regarded as autonomous method. 

BASIC MECHANISMS OF THERMAL DECOMPOSITION OF ORGANIC POLYNITRO AND POLYNITROSO COMPOUNDS... 

F, O. Rice and K. F. Herzfeld. The thermal decomposition of organic com pounds from the standpoint of free radicals. VI. The mechanism of some chain reactions. J. Amer. Chem. Soc., 56 284-289, 1934. 

S. Madorskii, Thermal Decomposition of Organic Polymers, Mir, Moscow (1967). 

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