Solvent Extraction of Iron(III) from Al Chloride Solution of Bauxite HCl Leaching by Mixture of Aliphatic Alcohol and Ketone

Artem Sokolov,Dmitry Valeev,Aleksandr Kasikov

doi:10.3390/met11020321

Abstract

Research into the solvent extraction of iron(III) from a chloride solution after bauxite HCl leaching by neutral oxygen-containing extractants and their mixtures were studied and the iron(III) extraction degree from chloride solutions using alcohols is presented. The effect of dilution of alcohol with a ketone by an extraction mixture in relation to its effectiveness was investigated. The iron(III) was efficiently extracted by the mixture of 1-octanol and 1-decanol (70%) with 2-undecanone (30%) from hydrochloric bauxite leach liquor at an O:A ratio = 2-4:1 at an iron(III) concentration of 7.4 g/L and 6 M HCl. For the removal of iron-containing organic phase from impurities (Al, Ca, Cr) that are co-extracted with iron(III), we used two step scrubbing at O:A = 5:1 by 7 M HCl as a scrub solution. The iron(III) stripping at the O:A ratio is shown. Using counter-current cascade of extractors, it was possible to obtain an FeCl3 solution with the iron(III) content of 90.5 g/L and total impurities less than 50 mg/L.

Highlights

It was found that using aliphatic ketones at 6 M hydrochloric acid (HCl) and 10 g/L of Fe(III), the iron(III) extraction degree decreased with an increase in the length of the ketone hydrocarbon radical, but was not less than 90%
The extraction of iron(III) with mixtures based on alcohols and ketones was studied
An industrial mixture of C8 + C10 aliphatic alcohols was used as the alcohol as it had the highest iron(III)

Summary

Introduction

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations. When using alkali methods (Bayer, sintering), iron remains in an alkali-insoluble residue-red mud [1,2]. To extract Fe2 O3 in a separate fraction, hydrothermal treatment with the addition of FeSO4 is used [3]. Another method involves the use of bauxite sinter after calcination with calcium carbonate (CaCO3 ) to further alkali leaching with the addition of Fe2+ to convert non-magnetic iron to magnetite (Fe3 O4 ) [4]. The reduction roasting method at 600 ◦ C is used to process high-iron bauxite The reduction roasting method at 600 ◦ C is used to process high-iron bauxite (Fe2 O3 > 20 wt. %)

Methods

Results

Conclusion