Abstract:
The aim of this investigation was to determine the effect of high-temperature heat treatment on the
electrical resistivity of charcoal. Samples of two different wood types (eucalyptus and black wattle)
were pyrolised in a retort at a temperature of 700°C and the resulting charcoals heat-treated in
an induction furnace at temperatures from 800°C to 1800°C and residence times from 60 to 120
minutes. After cooling, the resistivities of the samples were measured at room temperature using
the four-point probe technique. It was found that as the heat treatment temperature increased
the electrical resistivity of the charcoal decreased, approaching an asymptotic value at higher
temperatures. Longer residence times decreased the resistivity, but this effect was not pronounced.
