Production of liquid fuel from waste plastic using batch catalytic pyrolysis process

Abstract

Waste polystyrene from households and retailing shops are recognized to be the major sources of environmental problem. On the other hand, it represents a source of energy and valuable chemical products. Pyrolysis as a technique of chemical recycling of waste plastic is as an environmentally and economically acceptable option for converting waste plastics into useful resources. In this study, the operating conditions studied were; temperature was varied from 430 to 470°C with increment of 20°C, and residence time was varied from 30 to 60minutes with increment of 30minutes. High conversion of liquid; 49 percent in the presence of 12 gram catalyst. At higher catalyst quantity and lesser degradation temperature the yield of the liquid fuel became higher. The FTIR spectrum indicates there was a presence of Olefins, Naphtalenes, Amine, Acid and Aromatics group in waste plastic type. The liquid fractions were analyzed by GC/MS. The results showed that liquid oil from the catalytic pyrolysis of polystyrene plastic waste was enriched in styrene and consisted of a wide range of hydrocarbons mainly distributed within the C₅–C₂₇ that was in the range of gasoline, diesel and heavy oil. The liquid fraction that had high yield for polystyrene plastic type were also analyzed for fuel properties. From the study, liquid oil from polystyrene waste had a density, viscosity and a higher value of flash point and calorific value from PS waste.