Extraction of gallium from alkali solutions by N-(2-hydroxy-5-nonylbenzyl)-beta,beta-dihydroxyethylamine

摘要

Extraction of gallium and aluminum from NaOH solutions by N-(2-hydroxy-5-nonylbeEzyl)- beta, beta -dihydroethylamine (NBEA) is investigated. Based on data on the interphase distribution of gallium, infrared spectroscopy, and a calculation of the possible structures of the extracted complex by means of molecular mechanics, the composition and structure of the extracted RGa(OH)_2 are determined. An equation is proposed to describe extraction of gallium and aluminum by NBEA from alkaline solutions. It is shown that NBEA is an effective agent for recovery of gallium over a broad range of alkali concentrations (E_(Ga) approx 94-99 percent with C_(NaOH) 0.1 approx 5.0 mol/l). It is shown that it is possible to extract gallium from reuseable solutions in alumina production. Thus, from model Bayer solutions (C_(Ga) approx 0.3 g/l, C_(Al) approx 30 g/l, C_(NaOH) approx 3 mol/l), gallium is extracted at a rate of 20-58 percent with complete separation of the gallium from aluminum at the reextraction stage