Behavior of Cadmium and Lead Contained in Wood During the Carbonization Process

The behavior of heavy metals in wood during its carbonization process was examined. Cadmium in wood samples was found to be volatile when the samples were carbonized at 600°C or higher, which demonstrated that removal of cadmium was feasible. Meanwhile, lead was found to be barely volatile even if the wood samples were carbonized at 1,000°C or higher, which demonstrated that lead was difficult to remove and recover. The possibility of removing/recovering lead contained in wood by energization was then examined. By examining the concentration of sulfuric acid used as an electrolyte as well as load voltage, approximately 10% of lead was found to be recoverable.