US Patent 9147918 Effective recovery of lithium from lithium ion battery waste

A process for recovering Li-ions can include: providing a composition having Li-ions to be extracted therefrom; removing materials from the Li-ions; introducing one or more cyclic siloxane to the Li-ions so as to form one or more cyclic siloxane-Li-ion complexes; extracting the one or more cyclic siloxane-Li-ion complexes by one or more liquid-liquid extraction steps; separating an organic phase having the cyclic siloxane-Li-ion complexes from an aqueous phase; removing water from the organic phase; filtering the organic phase to obtain a filtrate; and obtaining one or more Li-ions (e.g., Li salts) from the filtrate.