Efficient removal of lead impurity for the purification and recycling of nickel from secondary sources based on ball-milling activated CaCO3

Efficient removal of impurity such as lead for nickel recycling from nickel-containing waste solution is become urgently necessary to supply nickel as possible to meet the tremendously increasing demand from wide industries particularly of battery production. In this study, CaCO3, abundant in nature but insoluble, was activated by mechanical ball milling and utilized to selectively precipitate lead from nickel-containing solutions. By optimizing the parameters including ball milling speed, experimental duration and dosage of CaCO3, within a wide Ni2+ concentration range, an excellent separation performance was achieved with 99.77% of Pb2+ ions removed by forming precipitation as PbCO3 and only 0.31% of Ni2+ loss accompanied. This simple and environmentfriendly technology may also be used in a wider range of mutual separation of heavy metal ions, showing great potential in the enrichment of target metal as well as the purification of heavy metal contaminated wastewater.

Automated summary

The study demonstrates efficient removal of lead impurity from nickel-containing waste solution using activated CaCO3, with excellent separation performance achieved and great potential for wider application in mutual separation of heavy metal ions and purification of heavy metal contaminated wastewater.