Characterization of the powder obtained from wasted tires reduced by pyrolysis and thermal shock process

Abstract

This paper reports on the physicochemical characterization of solid powder obtained directly from wasted tires through pyrolysis and thermal shock process. Two different processes to reduce wasted tires were performed in order to acquire the residuals in powder to be characterized and compared.During this research, three phases were observed when pyrolysis was applied to rubber: the first one a solid black phase formed by organic and inorganic compounds such as zinc oxide (ZnO) and zinc sulphur (ZnS); secondly a gaseous phase containing hydrocarbons i.e. aromatic compounds and, finally, a liquid phase formed by heavy and light oils. By using X-ray diffraction technique, the relationship between temperature and the presence of inorganic compounds was determined varying the temperature of pyrolysis. In addition to X-ray diffraction, infrared spectroscopy, thermal analysis and scanning electron microscopy were used to fully characterize the samples. Comparing the results observed in both processes, it was found that thermal shock process presents some advantages over the pyrolytic, i.e. energy consume and solid black phase production; however, by pyrolytic egradation a powder richer in carbon compounds is obtained.