The produced biochars exhibited a wide range of pH (8.1–11.3)
and water extractable DOC concentrations (0.04–0.36 mg g 1) in
R.-L. Zheng et al./Chemosphere 89 (2012) 856–862 857
the sequence of bran < husk < straw (Table S1). All biochars contained negligible amounts of water-extractable metals. The highest
levels of P and Si were measured in bran-char (3.6 mg g 1) and
straw-char (4.6 mg g 1), respectively (Table S2).