In the present study, Cu (II) removal from aqueous solution was performed in a micromixer by using D2EHPA solvent. The impact of nanoparticles addition, ultrasound wave irradiation and combination of them for improving mixing and mass transfer was investigated. The experiments were carried out in three different ultrasound input electrical powers (3.5-7 W). A constant concentration of nanoparticles (0.01 w/v) was employed in a reactor consists of a circular pit at its junction, and the results were compared with the Y-type microchannel (without Ultrasonic source). Depending on the mixing approach type and flow rate of the phases (1.875-6 mL/min), several separate flow patterns were observed, mainly slug, droplet, dispersed and parallel flow. The mass transfer coefficient (K(L)a) and removal efficiency (E) enhanced up to 251% and 53%, respectively. One of the benefits of the proposed techniques is a significant reduction in pressure drop compared with simple microchannels with the same volume. The highest amount of performance ratio (1.56) was observed in the presence of Fe3O4 nanoparticles under 7 W ultrasonic irradiation power. (C) 2016 Elsevier B.V. All rights reserved.