Thin-layer chromatographic separation of diphenylthiovioluric acid chelates

Abstract

Work on diphenylthiovioluric acid (DPHTVA) has shown that chelates formed by this reagent are extractable into various organic solvents. This has been made the basis of separation by TLC. Spectrophotometric determinations of iron (III), ruthenium (III) with DPHTVA have been recently reported [ 1-2]. Owing to the extractability of a large number of metalDPHTVA chelates, DPHTVA cannot be used as a selective reagent. In the present study, ions known to form DPHTVA chelates have been grouped bearing in mind, as far possible group similarity or the ability to form extractable DPHTVA chelates in the same pH range. The constituents of such groups of ions have been separated using TLC. Groups of ions investigated are: (i) Nickel (II), cobalt (II), copper (II) and iron (III). (ii) Ruthenium (III), platinum (IV) and palladium (II).