Y-Y microfluidic polymer/salt aqueous two-phase system for optimization of dye extraction: Evaluation of channel geometry

ABSTRACT

This study’s main purpose is to investigate the effect of the channel inlet angle on extraction efficiency. Also, the potential of microfluidic polymer/salt aqueous two-phase systems (ATPS) for removing methyl orange (MO) dye has been investigated. The simultaneous influence of independent factors including channel inlet angle, initial dye concentration, flow rate, and pH on the extraction efficiency of MO were investigated. The channel inlet angles of 30°, 60°, and 90° were evaluated. By increasing the inlet angle from 30° to 60°, the extraction efficiency increased from 52.76 to 72.80% at the optimum point. The values obtained at the optimum point were in good agreement with the design equations’ predicted values. At the optimal point, a suitable angle of 60°, an initial concentration of 113.4 mg/L, a flow rate of 1 mL/h, and pH=7 were obtained, which according to the predicted equation, the efficiency reaches 73.27%. In microchannels with a channel inlet angle of 60°, due to having a suitable ratio of top and bottom phases in the outlet of the microchannel and also due to the proper contact of the two phases in the channel inlet (the highest mass transfer section), mass transfer rate and extraction efficiency were increased.

Graphical Abstract

KEYWORDS:

• Microfluidic
• aqueous two-phase systems (ATPS)
• channel inlet angle
• microchannel geometry
• dye extraction

Highlights

• The effect of the channel inlet angle on extraction efficiency was investigated.

• Polymer/salt aqueous two-phase systems were applied to extract methyl orange.

• Box-Behnken design was performed to determine the optimum operational parameters.

• The highest mass transfer rate was achieved at the channel inlet angle of 60°.

Disclosure statement

No potential conflict of interest was reported by the author(s).