Gómez Ariza J L, Giráldez I, Sánchez-Rodas D, Morales E
Departamento de Quimica y Ciencia de los Materiales, Escuela Politécnica Superior, Universidad de Huelva, 21819 Palos de la Frontera, Huelva, Spain.
Talanta. 2000 Jun 30;52(3):545-54. doi: 10.1016/s0039-9140(00)00410-0.
This study considers the selectivity of the extractants used in a sequential extraction scheme for metals mobility assessment by analyzing individual mineral phases previously coprecipitated or sorbed with trace metals. The scheme evaluated was a modification of the Tessier et al. [A. Tessier, P.G.C. Campbell, M. Bisson, Anal. Chem. 51 (1979) 844] sequential procedure proposed by the authors. The phases studied were calcite, amorphous iron oxide, hausmannite, humic acid, kaolinite and illite. Selective extractions were obtained for As, Cr, Cu, Ni, Pb and Zn in metal-coprecipitated phases whereas NH(2)OH-HCl was not selective for the extraction of Hg and Cd coprecipitated in hausmannite and amorphous iron oxide, respectively. Otherwise, Cd, Hg, Ni and Zn sorbed on the different phases were released with MgCl(2) and NaOAc/HOAc, but stronger reagents were needed to release As, Cr, Cu and Pb.
本研究通过分析先前与痕量金属共沉淀或吸附的各个矿物相，考察了在用于金属迁移性评估的顺序提取方案中所使用萃取剂的选择性。所评估的方案是作者对Tessier等人[A. Tessier, P.G.C. Campbell, M. Bisson, Anal. Chem. 51 (1979) 844]提出的顺序提取程序的改进。所研究的相包括方解石、无定形氧化铁、黑锰矿、腐殖酸、高岭石和伊利石。对于共沉淀相中砷、铬、铜、镍、铅和锌的选择性提取得以实现，而羟胺 - 盐酸对分别在黑锰矿和无定形氧化铁中共沉淀的汞和镉的提取无选择性。另外，吸附在不同相上的镉、汞、镍和锌可被氯化镁和醋酸钠/醋酸释放出来，但需要更强的试剂来释放砷、铬、铜和铅。
