Pyrolysis of a wood chips mixture and main wood compounds such as hemicellulose, cellulose and lignin was investigated by thermogravimetry. The investigation was carried out in inert nitrogen atmosphere with temperatures ranging from 20°C to 900°C for four heating rates: 2 K min−1, 5 K min−1, 10 K min−1, and 15 K min−1. Hemicellulose, cellulose, and lignin were used as the main compounds of biomass. TGA and DTG temperature dependencies were evaluated. Decomposition processes proceed in three main stages: water evaporation, and active and passive pyrolysis. The decomposition of hemicellulose and cellulose takes place in the temperature range of 200–380°C and 250–380°C, while lignin decomposition seems to be ranging from 180°C up to 900°C. The isoconversional method was used to determine kinetic parameters such as activation energy and pre-exponential factor mainly in the stage of active pyrolysis and partially in the passive stage. It was found that, at the end of the decomposition process, the value of activation energy decreases. Reaction order does not have a significant influence on the process because of the high value of the pre-exponential factor. Obtained kinetic parameters were used to calculate simulated decompositions at different heating rates. Experimental data compared with the simulation ones were in good accordance at all heating rates. From the pyrolysis of hemicellulose, cellulose, and lignin it is clear that the decomposition process of wood is dependent on the composition and concentration of the main compounds.

Pyrolysis and combustion behaviors of a single rubber particle in a derivative thermogravimetric (DTG) apparatus were investigated. The influence of temperature (400-8508C) and oxygen content in gas (5-21%) on combustion behavior of rubber samples and solid products of the pyrolysis process (chars) was studied. Development of the porosity and specific surface area of the rubber particle during pyrolysis was investigated.Pyrolysis of scrap rubber samples was carried out under nitrogen atmosphere over a temperature range 20-8508C using a heating rate of 58C/min. The measured DTG curves show two different weight loss regions during the pyrolysis over a temperature range 250-5508C. In all, 52-55% of the samples weight was lost during the pyrolysis process and another 30% during the combustion of char. Ashes create approximately 17% of the samples weight.The ignition temperature of scrap rubber samples in air was around 5128C and increased with decreasing oxygen content. The reaction time of the combustion process decreased about 1.4 times with increasing temperature from 500 to 7508C and 5.5 times with decreasing oxygen content in the inlet gas from 21 to 5 mol%. The total specific surface area of the rubber sample with the degree of pyrolysis increased rapidly to 83 m 2 /g. The values of total porosity increased significantly from 0.3 to 32% at the end of pyrolysis.

The pyrolysis of rubber from the sidewall and tread of a passenger car tire was carried out in a nitrogen flow at a wide range of final temperatures. Derivative thermogravimetric analysis (DTG) was applied to examine the kinetics at the different process conditions of completed pyrolysis. Two characteristic stages were observed in the DTG curves. The first stage corresponded to the decomposition of processing oil, plastifier, and additives, whereas the rubber polymer was decomposed in the second stage. Several properties of the carbon black formed by the pyrolysis such as ash content, specific surface area, and pore size distribution were determined. A change of the internal structure of the rubber particle in the meso-and macroregions of the pore size was observed.

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Internal structure of carbon black produced by pyrolysis (CBp) of rubber samples from the top and bottom parts of sidewall and tread of a passenger car tire was investigated in nitrogen flow at different temperatures. The pore structure (specific surface area, pore size distribution, and porosity) of CBp and commercial CB, was compared. The development of pore structure and the increase of the specific surface area were most intensive during the thermal decomposition at temperatures ranging from 300°C to 500°C. This is caused by the intensive release of volatiles during the pyrolysis. After the pyrolysis was finished, at temperatures above 500°C, further decomposition of solid matter was associated with a slight increase of the specific surface area.