Catalytic Conversion of Waste Inner Tube Rubber (Isobutylene Isoprene) into Valuable Products

Abstract

Waste inner tube rubber (isobutylene isoprene) represents a source of energy and valuable chemical products. Waste inner tube rubbers were pyrolysed catalytically in a batch reactor under atmospheric pressure. Calcium carbide was used as a catalyst to explore its effect on pyrolysis product distribution. The effect of temperature, amount of catalyst and time on the yield of the pyrolysed products was investigated. The effect of catalyst on the liquid yield was also studied. The results demonstrate that the temperature has a promising effect on the yield; however high temperature, as well as high catalyst loading, caused a decline in liquid yield. In order to check possibility of further cracking of the liquid product it was refluxed with the same catalyst for 2 hours. For characterization of Viscosity, Kinematic Viscosity, Aniline Point, Flash point, Watson Characterization Constant, Freezing Point, Diesel Index, Refractive Index and ASTM distillation were applied according to IP and ASTM standard methods for fuel values. From the physical tests it was observed that the results for the liquid fractions are comparable with the standard results of physical tests for gasoline, kerosene and light oil. Phenols and carbonyls were quantitatively determined by spectrophotometric methods using folin-denis and phenyl hydrazine reagents respectively. The different hydrocarbons were separated by using column chromatography and fractional distillation.