Investigation on possible use of palm nutshells as reductant for the reduction of copper slag for copper recovery

The depletion of ores from the first sources on one hand has led to using damped materials that contain valuable metals to be recycled while environmental threats are being targeted and on the other hand high price of reductant coupled with their depletion have caused a stir in the metallurgical industry. Many slags are currently recycled for the recovery of valuable metals while new reductants are being tested for eventually replace the generic reductants. In this work, copper slag from Water-jacket furnace have been used to recover copper in presence of raw palm nutshells as possible replacement of generic reductants. Characterisation of the copper slag, the palm nutshells and products were conducted using XRD, XRF and SEM-EDS. Results have shown that dominants elements in the slag were Fe 33.83 wt%, Zn 6.73 wt%, Cu 1.26 wt%. Raw palm nutshells analyses revealed 6.39 wt% moisture, 61.56 wt% volatile matters and 4.35 wt% ash content while fixed carbon amounted to be 27.89 % and loss of ignition (LOI) 91.8 %. The reduction experiments were conducted in a horizontal tube furnace at 1300 °C under argon to create an inert environment and efficiently test the reducing capability of the palm nutshells. The composition of the metal produced revealed 41.84 wt% Cu, 26.41 wt% Co and 31.75 wt% Fe. However, it was noticed that the miscibility of the metal and the slag was prominent. As a first attempt, results showed very promising and further investigations are required to reveal optimums conditions.