方法名称 | 步骤 | 形态分级 | 提取试剂及条件 | 参考文献 | |
Tessier法 | I | 可交换态 | 16 mL 1 mol∙L−1 MgCl2,pH = 7,25℃振荡1 h | [22] [23] | |
II | 碳酸盐结合态 | 16 mL 1 mol∙L−1 CH3COONa,pH = 5,25℃振荡5 h | |||
III | 铁锰氧化物结合态 | 40 mL0.04 mol∙L−1 NH4Cl(25%CH3COOH),95℃断续振荡6 h | |||
IV | 有机结合态 | 6 mL 0.02 mol∙L−1 HNO3 + 5 mL 30% H2O2,85℃断续振荡2 h | |||
6 mL 30% H2O2,85℃断续振荡3 h | |||||
10 mL 3.2 mol∙L−1 CH3COONH4 (20% HNO3),25℃振荡0.5 h | |||||
V | 残渣态 | HF + HCl + HClO4 + HNO3消解 | |||
BCR法 | I | 酸可溶态 | 40 mL 0.11 mol∙L−1 CH3COOH,25℃振荡16 h | [22] [24] [25] | |
II | 可还原态 | 40 mL 0.5 mol∙L−1 NH2OHHCl,pH = 1.5,25℃振荡16 h | |||
III | 可氧化态 | 10 mL 8.8 mol∙L−1 H2O2,pH = 2~3,85℃断续振荡1 h | |||
10 mL 8.8 mol∙L−1 H2O2,pH = 2~3 | |||||
50 mL 1.0 mol∙L−1 CH3COONH4, pH = 2,85℃断续振荡1 h | |||||
IV | 残渣态 | HF + HCl + HClO4 + HNO3消解 | |||
优化连续提取法 | I | 活性态 | pH > 5时,20 mL HOAc溶液,pH = 2.88,25℃振荡16 h | pH < 5时,20 mL HOAc液, pH = 4.93,25℃振荡16 h | [22] |
II | 次生碳酸盐结合态 | pH > 5时,10 mL 1 mol/L NaOAc,pH = 5,25℃振荡5 h | - | ||
III | 次稳定态 | 40 mL 0.5 mol∙L−1 NH2OHHCl,pH = 1.5,25℃振荡16 h | |||
20 mL 8.8 mol∙L−1 H2O2,pH = 2~3,85℃断续振荡2 h | |||||
50 mL1.0 mol∙L−1 CH3COONH4,pH = 2,25℃振荡16 h | |||||
IV | 稳定态 | HF + HCl + HClO4 + HNO3消解 |