LANTANUM; TANAH JARANG

• Main Author: Nur Basir, Djabal
• Format: Theses
• Language: Indonesia
• Subjects: Kimia
• Online Access: https://digilib.itb.ac.id/gdl/view/3133
• Institution: Institut Teknologi Bandung

Methods that have been developed currently for the separation and purification of rare earth elements, REE's are solvent extraction by through immobilization of an extracting agent in a porous polymeric membrane. This methods beside could increse the transport selectivity, also the amount of carrier was very few. This technique is known as supported liquid membrane, SLM. Research toward transport and separation of REE's through SLM have been still relatively limited merely to single feed-binary mixtur, and one type of carrier. Factually, in natural form most of REE's are present alltogether. Based on the above mentioned, in this investigation pattern of transport at collecting lanthanum from Bangka monazite mineral by supported liquid membrane technique have been studied. The first stage SLM was separation of REE's with non REE's, the second stage SLM was collecting cerium (IV) from the other REE's, and the third stage SLM was collecting lanthanum (III) from the other REE's. The influence of mayor parameters at separation process, e.q.: pH of feed phase, type and concentration of membrane phase, and type and acid concentration in the receiving phase. All of the stage SLM used a porous polymeric membrane : PTFE (polytetrafluoroethylene) as the supporting membrane, by immersing in a mixture of TBP (trybuthylphosphate) and D2EHPA (di-2-ethylhexyl phosphoric acid) by the composition of concentration in solvent kerosene as carrier, and chloride acid in the receiving phase. The process selectivity separation of lanthanum (III) at the third stage SLM, the influence of mixture carrier composition (TBP : D2EHPA) in kerosene solvent were the major matter in the investigation. The separation of lanthanum from the other REE's, for studying of optimum condition of the influence major parameters made a mixture of the REE's simulation solution, e.q.: concentration of La was 120.0 ppm, concentration of Nd was 16.0 ppm, concentration of Gd was 2.0 ppm, and concentration of Lu was 0.4 ppm. Determination of the REE's total concentration was carried out by visible spectrophotometric with NAS (sodium alizarin sulfonat) as the colouring agent, absorbance of the solution was determinated at 534 nm as maximum wavelength. For the determination of REE,s specific concentration an ICP-AES has been adopted, at emission maximum wavelength in each specific of REE's, e.q : Ce at 418.66 nm, La at 408.316 rim, Nd at 401.225 nm, Gd at 342.247 rim, and Lu at 261.542 nm. Transport of REE's across SLM is expressed as relative percentage between the difference of initial and final concentration with respect to initial concentration. Transport of lanthanum across SLM in a mixture of the REE's simulation by optimum condition were pH of feed phase was 3.0, concentration of carrier composition (TBP : D2EHPA) was (0.3 : 0.7) M, and concentration of chloride acid of the receiving phase was 3.0 M. In this condition, separation factor of La toward Nd, Gd, and Lu : aLa,Nd 5.0297, aLa,Gd 8.1935, aLa,LU 11.9529, and the perity rate was increase from 86.31 % to 93.65 % with recovery was 93.8 %. This condition used collecting lanthanum from Bangka monazite mineral by supported liquid membrane technique, at the third stage SLM. In the initial research, optimum condition at the first stage SLM were pH of feed phase was 3.2, concentration of carrier composition (TBP : D2EHPA) was (0.25 : 0.75 ) M, and concentration of chloride acid of the receiving phase was 3.0 M. For the second stage SLM were pH of feed phase was 3.0, concentration of carrier composition (TBP : D2EHPA) was (0.25 : 0.75 ) M, and concentration of chloride acid of the receiving phase was 3.0 M. Collecting lanthanum from Bangka monazite mineral by supported liquid membrane technique at optimum condition in each of the stage SLM have been resulted lanthanum (III) with the perity rate of increase from 24.0 % before the process of SLM to 89.84 % after the process of SLM, with recovery was 75.72 %.