Removal of copper from aqueous solutions by cementation in a bubble column reactor fitted with horizontal screens

• Cementation of copper in a bubble column fitted with iron screens was studied.
• Effect of gas velocity, number of screens and physical properties was investigated.
• Rate of cementation was expressed in terms of the mass transfer coefficient (k).
• The data were correlated by dimensionless equation suitable for reactor design.

The kinetics of the cementation of copper ions from copper sulfate solution onto a horizontal single screen and an array of closely packed iron screens were investigated in a bubble column. Variables studied were physical properties of the solution, superficial gas velocity and number of screens per array. The rate of cementation was found to increase with increasing superficial gas velocity to a certain limit and then remains constant and increases with increasing the number of screens per array. The rate of cementation was expressed in terms of the liquid–solid mass transfer coefficient (k). The data were correlated by the equation:j=3.99Re.Fr−0.078.The high rates of mass transfer obtained in this work and the high area per unit volume of gas sparged fixed bed of horizontal screens to qualify them for building high space time reactors suitable for purification of hydrometallurgical leach liquors and removal of heavy metal from waste water by cementation.