Catalytic co‐pyrolysis of waste rubber and waste lubricants with waste copper catalyst into value‐added fuel

Abstract

The co-pyrolysis of waste rubber and waste lubricating oil was carried out in a batch steel pyrolyzer where waste copper was employed as a catalyst and the reaction conditions were optimized for achieving maximum oil yield. The waste rubber and lubricant were co-pyrolyzed in different ratios and their optimum ratio was found to be 4:1, respectively in terms of maximum pyrolysis oil conversion. About 44% oil yield and 75.5% total conversion of the reactants were achieved under the reaction conditions of 500°C temperature, 30 minute reaction time, 5.0 wt% of catalyst and heating rate of 0.5oCs−1. The non-catalytic pyrolysis yielded about 37.7% oil with 65.0% total conversion under similar reaction conditions. The catalytically produced oil was found to have a higher calorific value as compared to the non-catalytic oil. The catalytic pyrolysis oil was fractionated in gasoline, kerosene and diesel ranges and their fuel properties were investigated according to the ASTM methods. The results showed that the fuel properties of the oil fractions were comparable with that of corresponding standard fuels. The product oil samples were analyzed by means of Fourier-transform infrared spectroscopy spectroscopy and gas chromatography-mass spectrometry to investigate their chemical composition. It was found that the fraction distilled in the gasoline range had a hydrocarbon distribution in the range of C6 to C13, hydrocarbons identified in the fraction distilled in kerosene range were distributed from C6 to C16 and the fraction distilled in diesel range was composed of hydrocarbons distributed in the range of C11 to C26.