Abstract
High temperature reactivation of activated carbon used in phenolic wastewater treatment was investigated by using a 50mmφ fluidized bed reactor.
The spent carbon could not be regenerated merely by heating at 700°C in nitorogen. Most of the phenols adsorbed on the carbon were found to be decomposed into such gaseous products as hydrogen and methane but some carbonized into substances that adhered to the carbon.
In the steam reactivation at high temperatures, the spent carbon could be regenerated by raising the temperature and by extending the period of reaction. When the spent carbon was treated with steam at 800°C for 10min its specific surface area was fully restored while its methylene blue adsorption capacity was only partly restored, and the original adsorptive power of the carbon for phenolic wastewater treatment was practically restored.
Both sulfur and ash, which had accumulated on the carbon by adsorption, could not be removed even by high temperature reactivation.
Activated carbon particles suffered but slight from pulverization due to steam reactivation at high temperatures.
Since linear relations were observed between bulk density and other properties of the reactivated carbon, its properties could be predicted from its bulk density.
