Influence of Tire Formulation on the Products of Continuous Pyrolysis in a Conical Spouted Bed Reactor

Abstract

The pyrolysis of waste tires in continuous mode has been studied in a pilot plant provided with a conical spouted bed reactor, in the 425−600 °C range, by feeding two types of tire materials with different contents of natural and synthetic rubber. The properties of the pyrolysis products have been characterized using different techniques for both the volatile and solid fraction. The liquid has been analyzed by means of GC/MS, GC×GC and simulated distillation, and the residual carbon black by elemental analysis and surface characterization. Neither temperature nor tire composition has a significant effect on the yields of gas, liquid and residual carbon black fractions, but they considerably affect product properties. The contents of natural rubber and styrene−butadiene rubber in the tire have a significant effect on the liquid composition (contents of aromatics and interesting raw materials, such as styrene and limonene). The carbon black obtained at 600 °C has a high surface area and is suitable for active carbon production.