Characterization and Utilization of Char Derived from Fast Pyrolysis of Plastic Wastes

Abstract

HDPE plastic wastes were fast pyrolyzed at temperature of 400-450 °C and char (solid residues) obtained were collected and analyzed. Proximate and ultimate analyses showed that pyrolysis char had a large amount of volatile matter (51.40%) and fixed carbon (46.03%), small amount of moisture (2.41%) and little amount of ash (61.0%). Contents of carbon, hydrogen and nitrogen were found to be 42.65, 3.06, 0.43%, and 1.80%, respectively. Calorific value and density of the char were also determined and reported as 4,500 cal/g and 1.59 g/cm3, respectively. Char derived from the fast pyrolysis of HDPE plastic wastes was crushed into powder and extruded to produce briquettes. One kilogram of the char based briquette was used as a fuel for the combustion process (boiling water). Atmospheric-pressure thermal activation at 900 °C for 3 hours was performed to promote surface area and specific pore volume of the char. Undergoing such an activation process, BET surface area and pore volume of the char were increased by 55% and 44% whereas pore size was reduced by 5%, corresponding to the values of 16.77 m2/g, 0.2080 cm3/g and 496°A, respectively.