Removal of copper ion from wastewater by flotation

Abstract EN

Several industrial wastewater streams may contain heavy metal ions, which must be effectively removal before the discharge or reuse of treated waters could take place.

In this paper, the removal of copper (II) by foam flotation from dilute aqueous solutions was investigated at laboratory scale.

The effects of various parameters such as pH, collector and frother concentrations, initial copper concentration, air flow rate, hole diameter of the gas distributor, and NaCl addition were tested in a bubble column of 6 cm inside diameter and 120 cm height.

Sodium dodecylsulfate (SDS) and Hexadecyl trimethyl ammonium bromide (HTAB) were used as anionic and cationic surfactant, respectively.

Ethanol was used as frothers and the optimal removal conditions have been established.

Successful removals about (98 % ) and (76 % ) could be achieved for copper ions with SDS and HTAB, respectively.

Copper removal reached about 80% under the optimum conditions at low pH; at high pH it became as high as 98 % probably due to the contribution from the flotation of precipitated copper.

It was found that the presence of NaCl in the solution reduced the recoveries.

Adding ethanol at 1 % concentration increased the removal efficiency.

From the results the rate of flotation was found to be first order.