2011/10/28 by Zhiyong Zhou, Wei Qin, Yang Liu +1 · 1 citation
Engineering · Chemistry · #Extraction and Separation Processes #Radioactive element chemistry and processing #Metal Extraction and Bioleaching
paper · doi:10.1021/je200803h
To explore the feasibility of extracting lithium metal from brine sources, three salts, MgCl 2, CaCl 2, and NH 4 Cl, were selected as chloride sources, and the extraction equilibrium of lithium was studied with tributyl phosphate (TBP) in kerosene and FeCl 3 as a coextracting agent at different values of Fe/Li. The extraction mechanism for lithium with TBP in kerosene and FeCl 3 as a coextracting agent was investigated too. The results showed that the extraction of the lithium ion is a cation-exchange reaction, and the extraction of iron ion is the precondition of the extraction of lithium ion. All of the extractability of the iron ion increased with the chloride concentration with MgCl 2, CaCl 2, and NH 4 Cl as chloride sources, and the extraction capacity of lithium ion followed the sequence: MgCl 2 > CaCl 2 > NH 4 Cl, with recoveries from MgCl 2 as chloride sources being much higher than that for CaCl 2 and NH 4 Cl as chloride sources at all values of Fe/Li. There exists competitiveness between Li + and NH 4 +, Ca 2+, and Mg 2+ when combined to TBP and FeCl 3 and a salting-out effect of three salts. MgCl 2 benefits from weaker competitiveness and a stronger salting-out effect than the other two. Choosing MgCl 2 as chloride sources at Fe/Li = 1.9 obtains the highest partition coefficient with TBP/kerosene as an extractant and FeCl 3 as a coextracting agent.