Recovering renewable carbon materials from automotive shredder residue (ASR) for micro-supercapacitor electrodes

Abstract

Carbons utilised in the energy applications are often produced from non-renewable sources in harsh environments. By leveraging high temperature reactions, this study used thermal transformation to recover useful carbon materials from wood and plastic components of automotive shredder residue (ASR) and tune their properties in situ via selective thermal synthesis. The properties of the recovered activated carbon have been investigated over a range of temperatures between 600 and 1000 °C. The recovered activated carbon product presented a micro- and mesoporous structure which have the highest specific surface area of 1180 m2g-1. The electrochemical-capacitance performance of the activated carbon in electrochemical double layered capacitor (EDLC) electrodes was characterised using cyclic voltammetry (CV), galvanostatic charge-discharge (GCD) and electrochemical impedance spectroscopy (EIS) methods. The ASR derived activated carbon shows excellent specific capacitance of 275 F g−1 at a 5 mV s−1 scan rate by the CV method and 280 Fg-1 at 1 Ag-1 current density by the GCD method in a KOH (2M) electrolyte. This study demonstrates a facile way to recover the renewable carbon materials from a problematic and toxic waste streams. This pathway offers industry a feasible and sustainable source of carbons, while eliminating the lost of the valuable raw materials by landfilling.