Chemistry Department, Analytical Chemistry Division, Lomonosov Moscow State University, 1-3 Leninskie Gory, 119991 Moscow, Russian Federation.
Anal Chim Acta. 2013 Oct 10;798:109-14. doi: 10.1016/j.aca.2013.08.049. Epub 2013 Sep 7.
The reversible sorption preconcentration of noble metals (NMs) using different schemes "sorbent-reagent-eluent" was investigated. The extraction of Au, Pd, Pt, Ir, Rh and Ru chlorocomplexes from hydrochloric acid solutions on hyper-crosslinked polysterene MN-200 in the form of ion associates with tributylamine (TBA) and 4-(n-octyl)diethylenetriamine (ODETA) was investigated. It was found that Pd, Pt and Au were quantitatively and reversibly extracted using TBA on hyper-crosslinked polysterene; the appropriate eluent for desorption was 1M solution of HCl in ethanol. Ir, Rh and Ru under these conditions were not sorbed quantitatively. It was found that sorbent hydrophobicity is not the main characteristic that defines the efficiency of sorption of a particular NM ion associate. Different efficiencies of hyper-crosslinked polysterene MN-200 for sorption of square-planar chlorcomplexes of Pt, Pd and Au and octahedral complexes of Ir, Rh and Ru were found. For the first time, the sorbents with their own N-atoms - StrataX and StrataX-AW - were used for the sorption of Ir, Rh and Ru. Using these sorbents, the sorption of Ir was increased up to 95%, and the sorption of Ru and Rh was increased to about 40%. We can explain these results by nonspecific interaction of chlorcomplexes of Ir, Rh and Ru with ethylenediamine groups of the sorbent. Weak bases with large anions may be applied for desorption of Ir, Rh and Ru. Two schemes of dynamic sorption preconcentration of NMs from hydrochloric acid solutions were proposed - hyper-crosslinked polysterene MN-200 for the determination of Au, Pd, Pt, and StrataX-AW for Ir, Rh and Ru.
采用不同的“吸附剂-试剂-洗脱剂”方案研究了贵金属（NM）的可逆吸附预浓缩。研究了高交联聚苯乙烯 MN-200 以离子缔合物的形式从盐酸溶液中萃取 Au、Pd、Pt、Ir、Rh 和 Ru 的氯配合物，与三丁胺（TBA）和 4-（正辛基）二乙撑三胺（ODETA）。结果表明，TBA 可定量且可逆地萃取高交联聚苯乙烯上的 Pd、Pt 和 Au；用于解吸的合适洗脱剂是乙醇中的 1M 盐酸溶液。在这些条件下，Ir、Rh 和 Ru 没有被定量吸附。结果表明，吸附剂疏水性不是定义特定 NM 离子缔合物吸附效率的主要特征。发现高交联聚苯乙烯 MN-200 对 Pt、Pd 和 Au 的平面正方形氯配合物和 Ir、Rh 和 Ru 的八面体配合物的吸附效率不同。首次使用具有自身 N 原子的吸附剂 - StrataX 和 StrataX-AW 用于吸附 Ir、Rh 和 Ru。使用这些吸附剂，Ir 的吸附率提高到 95%，Ru 和 Rh 的吸附率提高到约 40%。我们可以通过 Ir、Rh 和 Ru 的氯配合物与吸附剂的乙二胺基团的非特异性相互作用来解释这些结果。具有大阴离子的弱碱可用于 Ir、Rh 和 Ru 的解吸。提出了从盐酸溶液中动态吸附预浓缩 NM 的两种方案 - 高交联聚苯乙烯 MN-200 用于测定 Au、Pd、Pt，以及 StrataX-AW 用于测定 Ir、Rh 和 Ru。
