An X-ray Study of the Surfactant Gel Extraction Method Separation Mechanismand Its Application to Separate Nickel(II) from Copper(II) and as Ammine-Complexes Using the Anionic Surfactant SDS

Abstract

A micellar solution of sodium dodecylsulfate (SDS) can separate into two phases due to a temperature change or the addition of salts. SDS plays the roles of a pairing-ion for ammine-complexes and of an extraction medium. The ion-pair extraction mechanism was investigated by SAXS and DSC measurements. This extraction was used for the separation of Cu(II) as a minor component from Ni(II) as a dominant component.

Surfactant Gel Extraction of Metal Ammine Complexes using SDS and KCl at Room Temperature, and a Small-angle X-ray Diffraction Study of the Surfactant Phase

“…Two 2.64° for KDS and 3.68° for CuDS. The latter is close to the angle of CuDS (3.56°), which was extracted at 0°C using SDS [22]. It seems confirmed the independent formation of CuDS, which had a lamellar structure.…”

“…Most of the copper was extracted without KCl because the melting point of CuDS, 77°C [22], is higher than room temperature. The melting points, which were measured by DSC, were 45°C and 91°C for NiDS and PdDS, respectively.…”

A possibility of surfactant application for boric acid extraction

“…Aqueous solutions of all classes of surfactantsanionic (Oxyphos B [7], alkylsulfonates and alkyl sul fates [8,9]), cationic (Catamine AB [10], alkylpyri dinium chlorides [11]), and non ionogenic (Synta mides [12], Syntanols [13])-can produce two liquid phases under the action of inorganic salting out agents. These systems proved to be efficient in metal extraction.…”