Iron Control in Liquid Effluents: Pseudo-Emulsion Based Hollow Fiber Membrane with Strip Dispersion Technology with Pseudo-Protic Ionic Liquid (RNH3+HSO4−) as Mobile Carrier

Abstract

The transport of iron(III) from aqueous solutions through pseudo-emulsion-based hollow fiber with strip dispersion (PEHFSD) was investigated using a microporous hydrophobic hollow fiber membrane module. The pseudo-protic ionic liquid RNH3HSO4− dissolved in Solvesso 100 was used as the carrier phase. This pseudo-protic ionic liquid was generated by the reaction of the primary amine Primene JMT (RNH2) with sulphuric acid. The aqueous feed phase (3000 cm3) containing iron(III) was passed through the tube side of the fiber, and the pseudo-emulsion phase of the carrier phase (400 cm3) and sulphuric acid (400 cm3) were circulated through the shell side in counter-current operational mode, using a single hollow fiber module for non-dispersive extraction and stripping. In the operation, the stripping solution (sulphuric acid) was dispersed into the organic membrane phase in a tank with a mixing arrangement (a four-blade impeller stirrer) designed to provide strip dispersion. This dispersed phase was continuously circulated from the tank to the membrane module in order to provide a constant supply of the organic solution to the fiber pores. Different hydrodynamic and chemical parameters, such as feed (75–400 cm3/min) and pseudo-emulsion phases (50–100 cm3/min) flows, sulphuric acid concentration in the feed and stripping phases (0.01–0.5 M and 0.5–3 M, respectively), metal concentration (0.01–1 g/L) in the feed phase, and PPILL concentration (0.027–0.81 M) in the carrier phase, were investigated. From the experimental data, different diffusional parameters were estimated, concluding that the resistance due to the feed phase was not the rate-controlling step of the overall iron(III) transport process. It was possible to concentrate iron(III) in the strip phase using this smart PEHFSD technology.

Treatment of Stainless Steel Rinse Waters Using Non-Dispersive Extraction and Strip Dispersion Membrane Technology

“…The hollow fibre module device used in the experimental work was obtained from Hoechst Celanese: Liqui-Cel 8 × 28 cm 5PCG-259 contactor and 5PC5-1002 Liqui-Cel laboratory LLE. The corresponding specifications were given in a previous publication [10].…”

“…The operational method was similar to that described in the literature [10]. A schematic view of the membrane operation, using one contactor in the recirculation mode of both the feed and pseudo-emulsion phases, is shown in Figure 1.…”

“…Following the same theoretical development as described in the literature [10], a final expression for the overall permeation coefficient can be written as:…”

“…Using hollow fibre modules, the transport of Fe(III) using a pseudo-protic ionic liquid derived from the primary amine Primene JMT and sulphuric acid was investigated [10]; in this work, acidic strip dispersion was used to recover the metal from loaded organic phases. The same hollow fibre strip dispersion technology was used to extract Pd(II) and Pt(IV) from synthetic and real solutions using alkoxymine-1-propylpyridinium derivatives [11].…”

Solvent Extraction of Au(III) by 2-ethylhexanol and Kinetic Modelling of the Facilitated Transport Across a Liquid Membrane

“…Moreover, in this PEHFMSD operation the organic and the receiving or stripping phase were mixed in one tank, and continuously pumped to the module, to improve the transport and the removal of the solute from the feed to the organic and from the organic to the receiving phases. This PEHFMSD operation was recently used in the removal of iron(III) [22] and in the treatment of stainless steel rinse waters [23]. It is worth to note that against all the literature favoring the use of liquid membranes in the treatment of wastewaters, these technologies seemed to be unpopular in the case of acid mine wastewater treatment [24].…”