Dispersion-Free Extraction of In(III) from HCl Solutions Using a Supported Liquid Membrane Containing HA324H+Cl- Ionic Liquid as Carrier

Abstract

The transport of indium(III), from HCl solutions, across a supported liquid membrane in flat-sheet configuration was investigated, being the carrier the ionic liquid HA324H+Cl- (derived from the tertiary amine Hostarex A324 and hydrochloric acid). Different variables affecting the metal transport: hydrodynamic conditions in the source and receiving phases, metal and HCl concentrations in the source phase, and carrier concentration in the membrane phase, were investigated. Also the transport of indium(III) using carriers of various nature: ionic liquids, alcohol, ketone, phosphine oxide and phosphoric ester, was compared. The metal transport was modelled describing the transport mechanism as: diffusion across the source diffusion layer, a fast interfacial chemical reaction, and diffusion of the InCl4--carrier complex through the membrane support. Diffusional parameters for the transport of indium(III), from the experimental data and the model, were estimated.

Effects of Process Factors on Performances of Liquid Membrane-Based Transfer of Indole-3-Acetic Acid

“…Correlation coefficients (r) summarized in Supplementary Table kmol/(m 2 •s), are consistent with those estimated in other related studies 17,37…”

“…(38) and (39) instead of c IAA,Ff,ex and c IAA,Sf,ex . The values of J IAA,tot,m , i.e., 0.382-4.418×10 -9 kmol/(m 2 •s), are consistent with those estimated in other related studies 17,37…”

“…Various techniques for the separation of carboxylic acids from aqueous solutions, including liquid-liquid extraction, adsorption, nanofiltration, ultrafiltration, ion exchange, electrodialysis, reverse osmosis, distillation, liquid membrane separation (LMS), have been intensively studied [10][11][12][13][14][15][16] . LMS has a series of advantages, e.g., fast and selective separation of target compounds, high transport efficiency, use in case of diluted solutions, low cost compared to other methods of separation, simple handling, easy to scale up [10][11][12][13][17][18][19][20] .…”

“…Mathematical modelling is an effective tool used to predict the performances of liquid membrane-based separation 11,[17][18][19][20]28,30,31 . Process performances depends on different factors, e.g., type and initial concentration of separating species in the feed phase, type of organic solvent in the membrane phase, type and concentration of carrier in the membrane phase, type and concentration of stripping agent in the stripping phase, type of separation equipment, stirring speed, temperature, pH of feed and stripping phases, volumes of feed, membrane, and stripping phases and their contact surface areas.…”