厦门港湾表层沉积物中腐殖酸铜铅络合物的表观稳定常数

APPARENT STABILITY CONSTANT OF Cu-AND PbHUMIC ACID COMPLEX FROM XIAMEN HARBOUR SURFACE SEDIMENT

从现场采集的厦门港湾表层沉积物中提取了腐殖酸,在近于该港湾表层沉积物腐殖酸含量、pH、痕量金属离子浓度和盐度等现场条件下,采用差示脉冲阳极溶出伏安法,测定了所提取的腐殖酸每个分子中可键合金属位置的平均数,并根据所测定的总酸性基当量浓度估算其平均分子量(约为850)。根据实验获得的平均意义上的化学计量式,估算出厦门港湾表层沉积物中腐殖酸的铜、铅络合物的表观稳定常数分别为2.0×10^(10)和4.5×10^(10)。

Humic acid has been extracted from in situ surface sediment in the Xiamen Harbour.The average potential bonding sites of each humic acid molecule were determined by DPASV on condition that acidity,pH,salinity and trace metal concentration were similar to the field conditions of surface sediment in the harbour and the average molecular weight(about 850)was estimated from the equivalant concentration of total acidic groups.The conditional stability constant of Cu-and Pb-humic acid complexes from the Xiamen Harbour surfade sediment was evaluated based on the average chemical formula obtained in the experiment(2.0×10^10 and 4.5×10^10 respectively).