Study shows novel heavy-metals-from-wastewater method

Scientists in Singapore and Saudi Arabia have reported a novel method for extracting toxic and valuable heavy metals from wastewater using forward osmosis (FO).

The researchers demonstrated the removal of chromium, arsenic, lead, cadmium, copper, and mercury. The process exploits a recently established type of draw solute formed from a complex of citric acid and cobalt. This is a large complex ion so reverse flux across the forward osmosis membrane is minimal.

At a flux of about 11l/m²/h heavy metals were harvested with rejections of 99.5% according to the researchers’ paper in the Journal of Membrane Science.

“The impressive heavy metal rejections and satisfactory water flux under various conditions suggest great potential for the newly developed FO system in the treatment of heavy metals wastewater,” the researchers said in their report.