Effects of Commercial Ni-Mo/ã-Alumina Catalyst on Pyrolysis of Blends of Waste Tire and Lignite
Effects of commercial Ni-Mo/γ-alumina catalyst on pyrolysis of blends of waste tire and lignite
Ozlem ONAY
Anadolu University, 26470 Eskisehir, Turkey
email:oonay@anadolu.edu.tr,Tel: +90 222 2241389, Fax:+90 222 2241390
Abstract
Waste tire is an increasing economic and environmental problem closely related with a rapid developing modern society. Pyrolysis can be considered as an optimal and environmentally friendly method for thermo-chemical conversion of wastes such as tires. Three products are derived from pyrolysis: gas with a high calorific value, pyrolytic oil that can be used as fuel or as a source of benzene, toluene, xylene (BTX) or limonene and char that can be used as fuel, activated carbon or carbon black.
The co-processing of waste tire with coal has been studied as a way to improve waste tire liquefaction. Co-pyrolysis of waste tire with can modify the composition of the oils so that it has a higher aliphatic/aromatic ratio. On the other hand, blends with catalyst of waste tire and coal were also prepared to modify the composition of the oils and to increase the percentage of aromatic compounds obtained from the co-pyrolysis of the waste tire and coal.
In the present work, the pyrolysis of waste tire and with lignite and their blends was carried out at 500°C in the absence and presence of Commercial Ni-Mo/γ-alumina catalyst (Criterion 424) in order to compare the yields and characteristics of the products obtained. At the lower blending coal ratio conditions, the oil yields are higher than the expected ones, calculated as the sum of oil fractions produced by pyrolysis of each separated component. The obtained oils are characterized by FTIR, 1H NMR, GC-MS and elemental analysis. The considerable synergetic effects were observed during the co-pyrolysis in a fixed bed reactor leading to increase in oil yield. The amount of aliphatics/aromatics can be increased by including a lignite in the pyrolysis process. The sulfur content of tire pyrolysis oils were also reduced by using catalyst. These findings can potentially help to understand and predict the behavior of waste tire/coal blends in practical liquefaction systems. The pyrolytic oil produced from waste tire and lignite can be used both as an energy source and feedstock for chemical production.
Keywords: Catalytic pyrolysis; Co-pyrolysis; Waste tire; Coal; Oil