Covalently Immobilized Nickel Nanoparticles Reinforce Augmentation of Mass Transfer in Millichannels for Two-Phase Flow Systems

Process intensification in millichannels is gaining momentum due to its wider applications and several operational advantages compared to microreactors. Nanoparticle-immobilized millimeter-sized channels have the potential to address the further enhancement of mass transfer by effective micromixing of a solute in the desired solvent. The present work provides a comprehensive study on the flow behavior and mass-transfer characteristics of nanoparticle-assisted systems. Toluene–acetic acid and water are chosen as model systems. A very little amount, 10 mg, of Ni nanoparticles has been immobilized for a 630 mm3 volume of the millichannel. It is observed that the introduction of nanoparticles contributes positively toward process intensification by increasing the range of slug flow and decreasing the range of transitions like slug annular and slug dispersed, which contribute poorly to the mass-transfer enhancement rate. Moreover, we have observed remarkable augmentation, a maximum of approx. 3.9 times of mass-transfer coefficients for nanoparticle-embedded systems.