Mass transfer study for the removal of copper ions from industrial wastewater using fluidized bed ion exchange reactor impingement with jet flow

Abstract

The removal of copper ions from industrial wastewater was investigated using a recirculating batch reactor consisting of a fluidized bed packed with a cation exchange resin and impinged by an axial turbulent submerged jet. The study systematically investigated the influence of key operating parameters, including the initial copper ion concentration, jet velocity, nozzle diameter, resin weight ($g/L$ of solution), and the distance between the nozzle jet surface and the bottom of the reactor on the mass transfer performance. The experimental results indicated that the mass transfer rate increases with an increase in jet velocity, nozzle diameter, and resin weight dosage, while the mass transfer rate decreases with an increase in the initial copper ion concentration. Moreover, an enhancement in mass transfer rate was observed as the distance from the nozzle jet surface to the reactor bottom decreased, reaching a maximum at an optimal distance at 3–4 cm, beyond which the rate declined with further distance decrease. The results showed that using a fluidized jet reactor increased the rate of mass transfer up to 55 times compared to natural convection, achieving a copper ion removal efficiency of 96% with a mass transfer coefficient of 0.2 cm/s in just 16 min. The mass transfer data obtained from the experiments were analyzed using dimensionless analysis and mathematically correlated to develop a dimensionless equation suitable for design and scale-up. The present data fit the correlation: $\mathrm{Sh}=7\ast {10}^{-5}{\mathrm{Re}}^{1.31}{\mathrm{Sc}}^{0.33}$ under the conditions 466.97 < Re < 4691.67, 1290.89 < Sc < 1416.53.