Zinc recovery from an effluent using Ionquest 290: From laboratory scale to pilot plant

A stream of effluent from a mine tailings pond, containing zinc, ferrous ions and other metals, required treatment to prevent pollution and recover valuable metals. A solvent extraction (SX) process using Ionquest 290 as extractant was developed to recover the Zn from the effluent. Ferrous ions were bio-oxidized and removed by selective alkaline precipitation prior to the zinc extraction. The Fe removal as well as the SX process were developed successfully at laboratory scale and verified in a pilot plant on-site, using two Bateman Pulsed Columns for the extraction and stripping of Zn. The results were satisfactory obtaining above 95% recovery of the Zn.