Pyrolysis of waste tire rubber: a comparative kinetic study using different models

With increase in number of vehicles worldwide the amount of waste tires is also increasing. These waste tires are either discarded to a dump site or burnt in open air. In both the cases they contaminate the soil, water and air. Due to its high heating value waste tire is a good source of energy if used under controlled conditions. In this connection pyrolysis has emerged as the ultimate solution for judicious use of waste tire. However, before going through the pyrolysis process on industrial scale, understanding the kinetics of pyrolysis reaction on laboratory scale is mandatory. Therefore, in this work our focus is on the kinetics of pyrolysis of waste tire using various kinetic models. Activation energy (E) and frequency factor (A) were determined and observed to increase with fraction conversion which shows a multistep reaction. TheEandAvalues calculated at different conversions were found in the range of 100.73-216.99 kJmol(-1)and 2.5 x 10(9)-9.0 x 10(13)min(-1)respectively. Based on kinetics parameters, a comparison among the different models was made. Any small variation in kinetics parameters was attributed to the selection of model chosen and the method adopted for investigation of kinetic results. The kinetic modeling will provide insights into pyrolysis reaction and the kinetic parameters determined will assist in pyrolysis of waste tire for its use as energy source on industrial scale.