Conversion of waste tires to liquid products via sodium carbonate catalytic pyrolysis

ABSTRACT

This study deals with the pyrolysis of waste tires supplied from the transport industry. The base material of tire is latex, which is derived from natural rubber trees. Nowadays rubber (Hevea brasiliensis) is a fast-growing tropical tree crop, which is being cultivated for latex and ultimately for tire production. Waste tires can be recycled for energy and valuable materials in many ways; however tire burning is the most common practice for heat generation. In recent years, the catalytic conversion of waste tires through pyrolysis into liquid, solid, and gas products was investigated. Liquids product was produced from the catalytic pyrolysis of waste tire at high temperature (up to 600°C) using sodium carbonate (Na₂CO₃) as a catalyst. Thermo-physical characteristics of the produced liquid samples showed that up to 85% of the produced oil can be used in internal combustion engines. Gasoline and diesel fuel contents in the liquid products are 45% and 40%, respectively. The gas chromatographic (GC) analysis of the volatile fraction of pyrolysis products showed styrene (28.1%) and butadiene (10.7%) as dominant compounds. The gaseous phase includes C₁–C₄ hydrocarbons (4.8%) and the liquid phase includes C₅–C₈ hydrocarbons (6.5%) of the total products.

KEYWORDS:

• Catalysis
• liquid fuels
• pyrolysis
• sodium carbonate
• waste tire