The interaction of long chain sodium carboxylates and sodium dodecylsulfate with lead(II) ions in aqueous solutions

Abstract

The interaction of sodium octanoate, decanoate or dodecanoate with lead(II) has been studied in aqueous solutions using potentiometry, electrical conductivity, turbidity and ICP-OES measurements. These show an alkyl chain length dependence on the behaviour. At the lead(II) concentration used (1.0 mM), relatively strong interactions are observed with the decanoate and dodecanaote, leading to formation of the lead carboxylates (soaps) as insoluble complexes. Association constants of the complexes have been determined from potentiometric measurements and are consistent with data on solubility products. A comparison is made of the effect of surfactant head group on the interactions with lead(II) using two surfactants with the same chain length: dodecanoate and dodecylsulfate. Differences in their interactions with this metal ion in aqueous solutions are interpreted in terms of greater covalency of the bond between the metal and the carboxylate than with the sulfate group.

Synthesis and aggregation properties of new biodegradable amphiphilic derivatives of p-tert-butylphenol for green separation of Gd(III) ions

“…Thus aggregation of the amphiphiles should be considered as both the competitive with and contributing to their binding with Gd(III) ions. Thus the above mentioned results indicate that the interaction of Gd(III) ions with the end carboxylates is tight enough to provide the predominant effect on the phase separation in the aqueous solutions of the amphiphilic molecules, which is in good confirmation with the previously reported regularities for long alkyl chain carboxylates [31,32]. Nevertheless the wrapping of polyetheleneoxide chains round [GdL 2 ] + complexes can be assumed as the additional interaction mode within the surfactantrich phase bound with Gd(III) ions, which differentiates the studied amphiphiles from the long alkyl chain carboxylates.…”

“…These tendencies are quite different from the concentration dependent turbidity followed by re-dissolution in aqueous solutions of sodium dodecylsulfate and lanthanide ions [31]. The observed regularities are more close to the interactions of long chain sodium carboxylates with metal ions in aqueous solutions, which are dependent on pH, concentration and alkyl chain length [32]. Nevertheless the observed difference between 1 and 2 indicates the effect of polyetheleneoxide length on the turbidity arisen from the interaction with Gd(III) ions, while the hydrophobic moieties are the same for the both amphiphilic molecules.…”

Reaction of Pb(II) and Zn(II) with Ethyl Linoleate To Form Structured Hybrid Inorganic–Organic Complexes: A Model for Degradation in Historic Paint Films

“…The observation that simple systems of a divalent metal ion with an unsaturated fatty acid ester give rise to stable, highly structured products provides insight into the studies of metal ion sequestration, stabilization, and toxicity in biological and ecological research. 15…”

Lead soaps in paintings: Friends or foes?

“…In addition to these imaging techniques, other methods, many of them macromolecular probes, have also been used and developed to probe the presence and nature of metal carboxylates in paintings: for example, thermogravimetric analysis (Bonaduce et al, 2012a,b), nuclear magnetic resonance (Verhoeven et al, 2006;Catalano et al, 2014a,b), potentiometry, electrical conductivity, turbidity (Pereira et al, 2014) and direct temperature-resolved time-of-flight mass spectrometry (van Loon et al, 2016). Even if such techniques are destructive and cannot always be applied to precious historical samples, they are of interest to understand reaction processes on model paints.…”