Effect of Biochar Pyrolysis Temperature on Chemical Immobilization of Pb and As in Contaminated Soils

Lead (Pb) and Arsenic (As) are major potentially toxic elements (PTEs) causing serious effects on soils and living organisms. Hence, the immobilization of PTEs is essential to maintain soil health. There are a variety of methods to immobilize PTEs in soils; and remediation using biochar soil amendment has been newly proposed. Objective of this research was to assess the effect of pyrolysis temperature of biochar for the immobilization of Pb and As in contaminated soils. The biochar were are produced from wood pellet with highly porous structure at four different pyrolysis temperatures, 400 °C, 500 °C, 600 °C, and 700 °C. The ability of the biochar to immobilize Pb and As in contaminated soils was investigated through a laboratory incubation for 30 days. Soil samples were analyzed for chemical and microbial properties such as pH, electrical conductivity, cation exchange capability, labile organic carbon, total C and N, and soil enzymes. The most suitable pyrolysis temperature will be found from the results to immobilize As and Pb contaminated soil.