Liquid–liquid extraction of palladium(II) and gold(III) with N-benzoyl-N′,N′-diethylthiourea and the synthesis of a palladium benzoylthiourea complex

Add time:08/14/2019    Source:sciencedirect.com

N-Benzoylthioureas have been reported to form complexes with gold (III) and palladium (II) and other transition metals. In this study, an N-benzoyl-N′,N′-diethylthiourea (3f) ligand was used in the solvent extraction of palladium(II) and gold(III) from aqueous chloride media (0.1 mol l−1 NaCl). The distribution coefficient was determined as a function of both metal concentration in the aqueous phase and extractant concentration in the organic phase. The experimental distribution data were numerically analysed by letagrop-distr software in order to obtain the thermodynamic model corresponding to the metal extraction. It is found that pH does not affect the metal extraction process in the 1–2 pH range. Synthesis of the palladium benzoyl thiourea complexes was carried out by mixing quantities of metal and ligand solutions in methanol in a 1:2 ratio stoichiometric. Yields of 74 and 80.9% were obtained for the Pd-3c and Pd-3f complexes. In order to confirm the formation of the palladium complexes, NMR, FTIR and MS analyses were performed. From MS analyses a complex stoichiometry 1:2 (metal:ligand) was confirmed. The formation of crystals of palladium N-benzoyl-N′,N′-diethylthiourea complex (Pd-3f) in the methanolic solution allows the characterisation of the complex structure by XRD. The resulting structure is described and discussed. Bis(1,1,-diheptadecyl-3-benzoyl-thioureate)palladium(II) (Pd-3c) and bis(1,1,-diheptadecyl-3-benzoyl-thioureate)palladium(II) (Pd-3f) were used as ionophores in polymeric membrane electrodes. Their potentiometric responses to different anionic metal chlorocomplexes are evaluated and discussed taking into consideration the results obtained in the liquid–liquid distribution studies. A nernstian response was only obtained for AuCl4 − (PDL=8.8×10−8) and PdCl4 2− (PDL=1.5×10−4 M) with a selectivity coefficient of KAuCl4-, PdCl42−pot=−3.4, calculated taking AuCl4 − as being the primary anion.

We also recommend Trading Suppliers and Manufacturers of N,N'-Diethylthiourea (cas 105-55-5). Pls Click Website Link as below: cas 105-55-5 suppliers

Prev:Enthalpies of combustion of two bis(N,N-diethylthioureas)
Next:The role of gold dopant in AP-Nb/MCF and AP-MCF on the Knoevenagel condensation of Ethyl cyanoacetate (cas 105-56-6) with benzaldehyde and 2,4-dichlorobenzaldehyde)