E–NETmix: A pioneering electrochemical flow reactor with enhanced mass transfer

Abstract

e–NETmix is an innovative electrochemical continuous-flow reactor with a static mixer characterized by a network of cylindrical chambers interconnected by prismatic channels arranged at 45° angles. This study focuses on the proof-of-concept of e–NETmix as regards global mass transfer properties by applying the limiting current technique for the ferricyanide-ferrocyanide reaction at different Reynolds numbers (Re). For Re from 100 to 1750, the volumetric mass transfer coefficients (kmA) ranged from ∼1.3 × 10−1 s−1 to ∼5.1 × 10−1 s−1 and the mass transfer coefficients (km) ranged from ∼6.8 × 10−5 m s−1 to ∼2.7 × 10−4 m s−1. A comprehensive comparison of the e–NETmix reactor with a commercial electrochemical flow reactor, the MicroFlowCell from ElectroCell (Denmark), revealed kmA and km values ∼63-fold and ∼8.6-fold higher in the new reactor, respectively, for similar Re. Moreover, the novel reactor showed mass transfer superiority over most existing reactors reported in the literature, allowing the attainment of kmA values up to ∼54-fold higher for similar mean linear fluid velocities (νavg) and km values up to ∼24-fold higher for similar Re. The superior performance of e–NETmix can be mainly attributed to the static mixer, which promotes convective mixing and the development of a laminar chaotic flow regime. This novel electrochemical flow reactor can be used to enhance several electrochemical and photoelectrochemical reactions.