Recycling Waste Polyurethane as a Carbon Resource in Ironmaking


  • James Ransford Dankwah University of Mines and Technology
  • W. K. Buah


Polyurethane, Composite pellets, Infrared gas analyser, LECO carbon/sulphur analyser, LECO oxygen/nitrogen analyser, Extent of reduction


Globally, major avenues available for recycling waste polyurethane are disposal at landfill sites and incineration. However, polyurethane contains high levels of carbon and hydrogen that can be recovered for use as reductant in metal extraction processes. In this work we report the use of post-consumer polyurethane as reductant for the production of metallic iron from iron oxide in a horizontal tube furnace through the composite pellet approach. Composite pellets were formed from mixtures of iron oxide and post-consumer polyurethane. The iron oxide-polyurethane composites were heated from room temperature to 1200 °C and then between 1200-1600 °C in a continuous stream of pure argon and the off gas was analysed continuously using an infrared (IR) gas analyser. Elemental analyses of samples of the reduced metal were performed chemically for its oxygen content using a LECO oxygen/nitrogen analyser. The extent of reduction was then determined at two temperatures 1200 °C and 1550 °C. Gas emission studies revealed the emission of large volumes of the reductant gas CO along with CO2. It is further demonstrated that post-consumer polyurethane is effective at reducing iron oxide to produce metallic iron with complete reduction achieved in less than 4 min at 1550 °C.

Author Biography

James Ransford Dankwah, University of Mines and Technology

Senior Lecturer and Head, Minerals Engineering Department


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Minerals Eng. Articles