Extractive separation, preconcentration, spectrophotometric and atomic absorption determination of gold as an ion associate with 2-[2-(4-methoxyphenylamino)vinyl]-1,3,3-trimethyl-3H-indolium chloride

Extraction of platinum with Astrafloxin FF from aqueous-organic solutions: Separative extraction-spectrophotometric determination of platinum(II) and platinum(IV) species

“…The ability of dyes from the polymethine series to form compounds usually referred to as ion associates with the anionic acid complexes of many elements [36]. Earlier, we demonstrated the effective ness of this approach to the development of proce dures for the extraction-spectrophotometric determi nation of palladium [37], zinc [38], copper [39], cobalt [40], and gold [41,42].…”

Solid Phase Extraction of Au and Pd by Silica Gel Functionalized With Triethylenetetramine for Determination by FAAS

“…Unfortunately, high concentrations of matrix components in rock, sediment, and metallurgical samples usually necessitate a preconcentration and/or separation procedure prior to the determination step. Some of these techniques also suffer from insufficient detection limits for the determination of Pd and Au at trace levels as encountered in most real sample analyses (4,6). In order to increase the concentration of Pd and Au, and to separate them from matrix ions, methods including fire assay (15), ionic liquid extraction (16), co-precipitation (17), dispersive liquid-liquid microextraction (3), cloud point extraction (18), and SPE (19)(20)(21)(22) have been used.…”

“…Au and Pd are found in rocks, ores, and soil at very low levels. For example, gold concentration in soil and ores is approximately 4 and 1 ng/g, respectively (4). Also, the wide use of catalytic converters in cars to reduce harmful species in exhaust gases results in an increase of Pd pollution of the environment.…”