2-nitro-4-nonylphenol-based extractant for selective extraction of lithium from carbonate precipitation mother liquors

Abstract

In this work, for the first time we proposed a mixture based on 2-nitro-4-nonylphenol as a lithium-selective binary extractant, in which the nitro group simultaneously participates in the formation of a six-membered metallocycle and increases the acidity of the phenolic group. The extraction of alkali metals (Li, Na, K) by a mixture of 2-nitro-4-nonylphenol and trioctylphosphinoxide in dodecane was studied in detail. The extraction of Li from mother liquors after Li2CO3 precipitation was considered as a practical application of the new binary extractant. It was shown that by using only liquid extraction methods, a high degree of concentration and purification of final product can be achieved. Mother liquor of Li2CO3 precipitation was concentrated by Li more than 50 times. Degree of lithium concentrate purification from Na and K was more than 5500 and 100,000 times, correspondingly.