Improvement in removal of Pb(II) using surfactant emulsion membrane from PCB wastewater by addition of NaCl

• The effect of addition of NaCl to the PCB wastewater was studied for extraction of Pb(II).
• An extraction efficiency of 99% was observed in the presence of NaCl whereas in its absence, the percentage had a lower value of 82%.
• In one step, more than 2.5 times enriched Pb(II) was achieved with very less interference of co-ions in the presence of NaCl.

The present manuscript discusses the removal of Pb(II) from printed circuit board (PCB) wastewater by using surfactant emulsion membrane (SEM) in the presence of NaCl. This SEM was prepared by stirring together the strip phase (sulphuric acid) and organic phase (surfactant: Span 80, extractant: D2EHPA, diluent: n-Hexane) using high speed homogenizer. The feed phase consisting of various metal ions (Na, Ca, Mg, Co, Zn, Mn, W and Pb) was treated with emulsion phase by maintaining a treat ratio 1:10. The parameters such as the extractant concentration, internal phase concentration and contact time were studied and optimized. Further, the effect of addition of NaCl salt to the feed phase was considered using the optimized parameters. A significant improvement of extraction efficiency of 99% was observed in the presence of NaCl with more than 2.5 times enrichment as compared to 82% extraction with 1 times enrichment in the absence of salt. Thus, the NaCl addition has a remarkable effect on the selective removal of Pb(II) from wastewater.

The surfactant emulsion membrane process has shown the potential in removal of Pb(II) from PCB recycling unit wastewater in the presence of NaCl.Figure optionsDownload as PowerPoint slide