The solvent extraction behavior of precious metal palladium with 1-phenyl-3-methyl-4-benzoyl-5-pyrazone (PMBP) into molten paraffin wax has been studied in the temperature range from 55 to 75 °C. The complex consisting of PMBP and palladium was extracted into molten wax phase in the pH range from 1.0 to 3.5 at 60 °C. The extraction efficiency was up to 97% at the experimental pH. The stoichiometry of the extracted species of palladium was determined on the basis of slope analysis method. The effects of time to achieve equilibrium, temperature, and extractant concentration on the extraction were discussed. The thermodynamic data indicate that the extraction is an endothermic reaction and the increase of temperature promotes the extraction of palladium into molten paraffin wax and the extraction of palladium with PMBP is entropy controlled at high temperatures.
If the inline PDF is not rendering correctly, you can download the PDF file here.
 R.L. Wu and W.L. Huang: “The Analysis Application of Solid State Extraction method in Precious Metal”, Anal. Laboratory, Vol. 7(9), (1988), pp. 34–39 (in Chinese).
 B. Peng, H.Y. Fan and J.Z. Gao: “Solid-liquid solvent extraction of metal ions”, J. Univ. Sci. Technol. Beijing, Vol. 10(1), (2003), pp. 1–7.
 Y.Q. Wan, L. Guo and C. Dai: “Determination of Trace Palladium by Paraffin Phase Spectrophotometry”, Chinese J. Anal. Chem., Vol. 28(5), (2000), pp. 606–608 (in Chinese).
 Y.Q. Wan, K. Liao and T. Gong: “Study on the Determination of Trace Gold in Ore by Paraffin Phase Spectrophotometry”, Chinese J. Anal. Chem., Vol. 28, (2000), pp. 1563–1565 (in Chinese).
 G.R. Choppin and J.N. Mathur: “Paraffin Wax As A Diluent for Extraction of Actinides and Lanthanides With TBP”, Solvent Extr. Ion Exc., Vol. 16, (1998), pp. 459–469. http://dx.doi.org/10.1080/07366299808934534
 G.R. Choppin and J.N. Mathur: “ParaffinWax — TOPO, an Extractant for Actinides and Lanthanides”, Solvent Ext. Ion Exc., Vol. 16, (1998), pp. 739–749. http://dx.doi.org/10.1080/07366299808934550
 J.Z. Gao, Q.L. Deng, B. Peng and X.Q. Guo: “Paraffin wax as a diluent for extraction and separation of trivalent gallium, indium, and thallium with 2,6-bis-(1′-phenyl-3′-methyl-5′-oxopyrazole-4′) pyridineacyl”, Rare Metals, Vol. 22(2), (2003), pp. 86–90.
 Q.L. Deng, X.Q. Guo, B. Peng and J.Z. Gao: “Synthesis of 2, 6-Bis(1′-Phenyl-3′-Methyl-5′-Oxopyrazole-4′) Pyridinediacyl and Its Solid-Liquid Extraction Behavior for Ce(˘ó) 420–423”, J. Chin. Rare Earths, Vol. 20(5), (2002), pp. 420–423.
 J.Z. Gao: “Recent progress in the determination of gallium, indium, and thallium”, Rare Metals, Vol. 24(1), (2005), pp. 1–7.
 M. Merdivan, A. Güngör, Ş. Savaşci and R.S. Aygün: “Extraction of some transition metals with N,N-dibutyl-N′-benzoylthiourea into molten paraffin at 65°”, Talanta, Vol. 53, (2000), pp. 141–146. http://dx.doi.org/10.1016/S0039-9140(00)00464-1
 M.A. Taher: “Flame Atomic Absorption Spectrometric Determination of Trace Lead after Solid-Liquid Extraction and Preconcentration Using 1-(2-Pyridylazo)-2-naphthol”, Croat. Chem. Acta, Vol. 76(1), (2003), pp. 273–277.
 J.Z. Gao, B. Peng, H.Y. Fan and J.W. Kang: “Spectrophotometric determination of palladium after solid-liquid extraction with 1-(2-Pyridylazo)-2-naphthol at 90°”, Talanta, Vol. 44, (1997), pp. 837–842. http://dx.doi.org/10.1016/S0039-9140(96)02122-4
 Y.Q. Wan, L.X. Shen and L. Guo: “Study on the Determination of Microamount of Palladium”, Chinese J. Anal. Laboratory, Vol. 19(1), (2000), pp. 30–32 (in Chinese).
 T. Gong and Y.Q. Wan: “Determination of Trace Palladium by Paraffin Phase Spectrophotometry”, J. Anal. Sci., Vol. 19(2), (2003), pp. 163–105 (in Chinese).
 A.I. Vogel: A Text Book of Quantitative Inorganic Analysis, 3rd ed., Longmans Green, ELBS, London, 1961, pp. 512–513.
 Y.J. Dong and S.L. Song: “Extraction Mechanism of Palladium with 1-phenyl-3-methyl-4-benzoyl-5-pyrazone (PMBP) from Perchloric Acid Medium”, Chinese Hydrometallurgy, Vol. 20(1), (2001), pp. 149–151 (in Chinese).
 T. Sekine and Y. Hasegawa: Solvent extraction chemistry (Fundamentals and Applications), Chinese Translation, Atomic Energy Press, Beijing, 1981, p. 354.