Ultrasonic Assisted Microchannel Extraction of Fe(III) from Wet-Process Phosphoric Acid

Abstract

An ultrasonic assisted microchannel extraction (UAME) method was developed for the extraction of Fe(III) from wet-process phosphoric acid with di(2-ethylhexyl)phosphoric acid (D2EHPA). The influences of ultrasonic power, extractant concentration, water phase velocity and the ratio of the organic and aqueous phases (O/A) on the extraction rate of Fe(III) were systematically studied. The results showed that the extraction efficiency of Fe(III) reached 91.08%, which was significantly higher than that for ultrasound extraction and microchannel extraction respectively. Response surface methodology was adopted to obtain the optimal conditions and to evaluate the significance of variables affecting the extraction efficiency. The extraction efficiency of Fe(III) reached 92.24% under the following optimum conditions: extractant concentration, 2.1 mol/L; aqueous phase velocity, 0.055 mL/min; ratio of organic phase and aqueous phase, 2.98.

Ultrasound-Assisted Micro-Channel Extraction of Magnesium from Wet-Process Phosphoric Acid

“…Usually, commercial phosphoric acid is produced via hot-process or wet-process. And due to the low-cost and low-energy advantages of the wet-process, 90% of phosphoric acid is produced through the wet-process [2][3][4]. However, many impurities are introduced into WPA (wet-process phosphoric acid) production, and Mg may be the most annoying impurity because it can increase the viscosity of WPA [4][5][6].…”

“…In a typical microfluidic reactor like the micro-channel, the organic phase and aqueous phase are limited in a specific space, leading to the enhancement of the mass transfer because of the significant increase of interface area and contact opportunity [27][28][29][30]. In our previous work, the extractant D2EHPA had shown great efficiency for the extraction of Fe 3+ in the UAME system [2,3]. However, D2EHPA showed less efficiency when dealing with Mg 2+ in WPA.…”