International Conference On Chemical Sciences (ICCS-2007) International Conference On Chemical Sciences (ICCS-2007) Innovation In Chemical Sciences For Better Life Innovation In Chemical Sciences For Better Life Yogyakarta-Indonesia, 24-26 May, 2007 Yogyakarta-Indonesia, 24-26 May, 2007 ANL/17-3 Separation of La(III), Ce(III), Pr(III) and Nd(III) using Solvent Impregnated Resin (SIR) Ibnu Khaldun 1* , Buchari 2 , Aminudin Sulaeman 2 , M. Bachri Amran 2 1 Jurusan Kimia Fakultas KIP Universitas Syiah Kuala Banda Aceh 2 Program Studi Kimia Fakultas MIPA Institut Teknologi Bandung ABSTRACT Separation of rare earth elements (REEs) with solvent impregnated resins (SIR) using di(2- ethylhexyl)phosphoric acid (D2EHPA) and Amberlite XAD-16 as a polymeric support by a dry method has been studied. The effect of contact time on the separation of La(III), Ce(III), Pr(III) and Nd(III) ions with (D2EHPA-resin = 10/90, 20/80, 40/60, 50/50, 60/40 wt%) at pH 3,0 has been chiefly investigated. The results demonstrated that La(III)/Ce(III) ions at pH 1,00 and Ce(III)/Pr(III) at pH 3,50 and also Pr(III)/Nd(III) ions at pH 2.50 could be separated with separation factor (α), = 5,47; = 3,03 and = 5.46 respectively. La Ce α Ce Pr α Pr Nd α Keywords: Solvent impregnated resin, D 2 EHPA, Rare earth. INTRODUCTION Rare earth elements have been increasingly used in the field of chemical engineering, metallurgy, nuclear energy, optical, magnetic, luminescence and laser materials, high-temperature superconductors and secondary batteries, catalysis, and red phosphors [1] . The high value of rare earths elements depends on their effective separation into high purity compounds. The separation of the natural rare earths elements mixtures into the individual elements is very difficult to achieve, due to the very low separation factors involving the adjacent of them [2] . The separation of the other rare earths elements, usually carried out by solvent extraction [3] or ion exchange [4] , is based on systematic differences in their basicity, which decreases from La to Lu. Nevertheless, this technique has several limitations such as environmental pollution, in terms of organic waste disposal, and the involvement of a multistage extraction and back-extraction in order to get successful separation. Also, ion exchange resins have lower extraction selectivity for rare earths elements, poor metal sorption capacity, and moderate exchange kinetics [5] . As an alternative approach, Warshawsky have been proposed solvent impregnated resins (as known as SIR) for selective separation of metal ions by direct adsorption of the extractant into macroporous polymeric supports. Impregnated resins bridge the gap between solvent extraction and ion exchange. They combine the advantages of solvent extraction systems such as fast mass transfer rates, high distribution and selectivity factors, with the advantages of solid ion-exchange technology such as simplicity of equipment and operation and applicability for processing very dilute solutions. [6] For these reasons, SIRs have been widely used in metal recovery and separation of minor actinides from the high level waste solution, [7] hydrometallurgical applications for the separation of rare earths elements, [8] precious group metals, [9] base metals [10] and also amino acid. [11] The present work aimed to investigate the extraction of La(III), Ce(III), Pr(III) and Nd(III) from nitrate media with bis(2-ethylhexyl)hydrogen phosphate (D2EHPA) as extractant and Amberlite XAD-16 as a polymeric support. D2EHPA is one of the first and most extensively investigated extractants in the separation of rare earth elements. It also has been impregnated into porous, nonpolar resin to prepare solvent-impregnated resin for the application in the separation process. [12] EXPERIMENTAL Reagents and chemicals D2EHPA was the product of Merck Co. It had a purity of about 98.5% and was used without further purification. The Amberlite XAD-16 resin (styrene– divinylbenzene copolymer, surface area: 800 m 2 g -1 , pore diameter: 10 nm and bead size: 20–60 mesh) was supplied by Sigma. The water used throughout the work was deionized by a Millipore Mini-Q system. All other reagents used were of analytical grade. Standard stock solutions (1000 μgmL -1 ) of La 3+ , Pr 3+ and Nd 3+ from La 2 O 3 , Pr 6 O 11 and Nd 2 O 3 (Aldrich, Fig. 1. Structure formulae of the extractant D2EHPA and resin Amberlite XAD-16 * Corresponding author. Email: ibnukhdn@yahoo.com