PEMISAHAN Zr – Hf SECARA SINAMBUNG MENGGUNAKAN MIXER SETTLER

Abstract

PEMISAHAN Zr – Hf SECARA SINAMBUNG MENGGUNAKANMIXER SETTLER. Telah dilakukan pemisahanZr – Hf secara sinambung menggunakan pengaduk pengenap (mixer settler) 16 stage. Larutan umpan adalah zirkon nitrat dengan kadar Zr = 30786 ppm dan Hf = 499 ppm. Ekstraktan dipakai adalah solven 60 % TBP dalam kerosen dan larutan scrubbingyang dipakai adalah asam nitrat 1 M. Umpan masuk pada stageke 5 dikontakkan secara berlawanan arah dengan solven masuk pada stage ke 16 dan larutan scrubbing masuk pada stage ke 1. Tujuan penelitian ini adalah memisahkan unsur Zr dan Hf dari hasil olah pasir zirkon menggunakan solven TBP dengan alat mixer settler16 stage. Analisis umpan dan hasil proses pemisahan untuk zirkonium (Zr) dilakukan dengan menggunakan alat pendar sinar-X, sedangkananalisis unsur hafnium (Hf) menggunakan Analisis Pengaktifan Neutron (APN). Parameter penelitian dilakukan dengan variasi keasaman asam nitrat dalam umpan dan variasi waktu pada berbagai laju pengadukan. Hasil penelitian pemisahan unsur Zr dengan Hf diperolehkondisi optimum pada keasaman umpan 4 N HNO3, keseimbangan dicapai setelah 3jam dan laju pengadukan 3300 rpm. Hasil ekstrak unsur zirkon (Zr) diperoleh kadar sebesar 28577 ppm dengan efisiensi 92,76 % serta kadar pengotor hafnium (Hf) sebesar 95 ppm.Kata Kunci: pemisahan Zr, Hf, ekstraksi, mixer settler, alat pendar sinar-X, APN. SEPARATION of Zr - Hf CONTINUOUSLY USE THE MIXER SETTLER. Separation of Zr - Hf continuously using mixer settler 16 stage has been done. The feed solution is zircon nitrate concentration of Zr = 30786 ppm and Hf = 499 ppm. As the solvent used extractant 60 % TBP in 40 % kerosene. Nitric acid solution used srubbing 1 M. The feed entered into stage to 5 is contacted with solvents direction on the stage to 16 and the scrubbing solution enter the stage to 1. The purpose of this study is to separate Zr and Hf of the results from the process of zircon sand using solvent TBP using 16 stage mixer settler. Analysis of the feed and the results of the separation process for zirconium (Zr) using X-ray fluorescence instrument which hafnium (Hf) using Neutron Activation Analysis (AAN). Parameter study done of acidity variation of nitric acid in the feed and time variation in various stirring speed. From the research the separation of Zr-Hf, the optimum conditions in acidity feed 4 N HNO3, equillibrium was received after 3 hours, and stirring speed of 3300 rpm obtained extract of zircon (Zr) concentration = 28577 ppm (effisiency of Zr = 92,76 %)with impurities of hafnium (Hf) = 95 ppm.Keywords: separation of Zr, Hf, extraction, mixer settlers, X-ray fluorescence, NAA.

Optimization and Kinetics of Zirconium Oxychloride (ZOC) Dissolution Using HNO₃

“…After going through several separation studies, in 2016 CSAT decided on the method of separating Zr and Hf by extracting solvent using a mixer-settler [5]. The selection of extract solvent used was tributyl phosphate (TBP), taking into account the distribution efficiency (KD) Zr into the organic phase which is quite high [5]. Solvent extraction of TBP has been carried out by previous researchers since 1955 by Cox et al [6].…”

“…The optimization will be carried out as a function of contact time, nitric acid concentration, temperature and stirring speed while the kinetics of the Shrinking Core Model was chosen because it matches with the ZOC dissolution system in nitric acid which was classified as Fluid-Particle Reactions [14]. The optimization and kinetics dissolution of ZOC data were expected to be used to make ZOC dissolution reactor design [14], before entering into the extraction process using a mixer settler [5].…”