Thermo-catalytic degradation of low density polyethylene to liquid fuel over kaolin catalyst

Abstract

Waste low-density polyethylene samples were subjected to thermo-catalytic degradation using kaolin as catalyst in a batch reactor at temperature range of 400 to 500 C and atmospheric pressure. The quality and yield of the condensable product has been studied as a function of temperature and amount of catalyst. Both in thermal and catalytic degradation, the condensable fraction was less viscous liquid oil at low temperatures (up to 450 C), whereas with increase of temperature (from 475 C) the fraction became viscous and waxy. The recovery of condensable fraction increased from 30.8 wt.% at 400 C to 71.45% at 450 C and further increased to a maximum of 86.65wt.% at 500 C in absence of catalyst. The catalyst increased the yield of the condensable product and decreased the reaction time. The highest yield of liquid fraction at 450 C was 79.5 wt.% with 1:2 catalyst to plastics ratio. The composition of the oil obtained at optimum reaction condition was characterised by gas chromatography-mass spectroscopy (and found consisting of paraffins and olefins with mainly C10-C16 components. Fuel properties of the oil obtained by different standard methods are similar to petrochemical fuels. 2014 Inderscience Enterprises Ltd.