Table of Contents
Journal of Catalysts
Volume 2014 (2014), Article ID 386371, 9 pages
http://dx.doi.org/10.1155/2014/386371
Review Article

Biocrude Production through Pyrolysis of Used Tyres

1School of Chemical and Metallurgical Engineering, University of the Witwatersrand, 1 Jan Smut Avenue, Braamfontein, Private Bag 3, Johannesburg 2050, South Africa
2Department of Chemical Engineering, Faculty of Engineering, University of Benin, P.M.B. 1154, Benin City, Edo State, Nigeria

Received 27 January 2014; Revised 16 April 2014; Accepted 17 April 2014; Published 15 May 2014

Academic Editor: Murid Hussain

Copyright © 2014 Julius I. Osayi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

A review of the pyrolysis process of used tyre as a method of producing an alternative energy source is presented in this paper. The study reports the characteristics of used tyre materials and methods of recycling, types and principles of pyrolysis, the pyrolysis products and their composition, effects of process parameters, and kinetic models applied to pyrolysis. From publications, the proximate analysis of tyre rubber shows that it is composed of about 28.6 wt.% fixed carbon, 62 wt.% volatile material, 8.5 wt.% ash, and 0.9 wt.% moisture. Elemental analysis reveals that tyre rubber has an estimated value of 82 wt.% of C, 8 wt.% of H, 0.4 wt.% of N, 1.3 wt.% of S, 2.4 wt.% of O, and 5.9 wt.% of ash. Thermogravimetry analysis confirms that the pyrolysis of used tyre at atmospheric pressure commences at 250°C and completes at 550°C. The three primary products obtained from used tyre pyrolysis are solid residue (around 36 wt.%), liquid fraction or biocrude (around 55 wt.%), and gas fraction (around 9 wt.%). Although there is variation in the value of kinetic parameters obtained by different authors from the kinetic modeling of used tyre, the process is generally accepted as a first order reaction based on Arrhenius theory.