Speciation Modeling Of LREEs-NTA Complexes On Anion- Exchange Resins
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چکیده
Conventionally, the sorption methods of rare earth elements were done with cationic ion exchangers. The present work was mainly oriented to find an alternative method for sorption of light rare earth elements (LREEs) based on anionic ion exchangers. Two different anionic exchangers have been tested including Dowex-1 and Sybron SR-7. The selection of these two exchangers was mainly done to investigate the effect of chain length in the polymeric structure on the sorption performance of REEs complexes. Dowex-1 contains tri-methyl amine while SR-7 contains longer chain length of tri-propyl amine as a function group. Sorption of LREEs complexes with nitrilotriacetic acid (NTA) on the two anionic exchangers has been tested by batch technique at various pH and metals concentrations. Aqueous speciation modeling was applied to predict the chemical species distribution of REEs complexes at various pH value of the aqueous phase.
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تاریخ انتشار 2013