Study on waste tires pyrolysis characteristics and high-value oil: Effects of pyrolysis parameters and catalyst

Pyrolysis is a green and efficient way to treat waste tires, but the complexity of pyrolysis products limits its high value utilization. To improve the value of pyrolysis products, especially pyrolysis oil, herein the pyrolysis process of waste tire was studied through thermogravimetry (TG) experiment and Pyrolysis gas chromatography-mass spectrometry (Py-GC/MS). The effects of pyrolysis temperature, heating rate, raw material particle size and catalyst on the pyrolysis products of waste tire were studied through fixed bed experiments. The results showed that the pyrolysis process of waste tire could be divided into three stages, additives, rubber and macromolecular substances pyrolyze in turn with the increase of temperature. After conducting comparative experiments, we discovered that rapid pyrolysis, lower temperature and smaller particle size were the most favorable for the formation and quality improvement of the oil. Both ZSM-5 and SAPO-34 could increase the olefins and cycloolefins contents and decrease the Monocyclic aromatic hydrocarbons (MAHs) content. SAPO-34 had stronger acidic site and more micropores compared with ZSM-5, which showed a better catalytic effect. This study provides a theoretical basis for the high value utilization of products and the targeted regulation of target products.