Abstract
Nano–filtration (NF) membranes can selectively separate dissolved multivalent ions and monovalent ions generally. However, one downside of conventional ones is their vulnerability to highly acidic/alkaline solutions, limiting their application to solution in the neutral region. Another is insufficient selectivity for multivalent ions, hampering separation efficiency. Under these circumstances, we successfully created a highly durable & selective NF membrane. Additionally, we have developed a new membrane process utilizing this new membrane for resource recovery applications. Regarding the application to resource recovery of lithium from used lithium–ion batteries (LIBs), we are succeeded in recovering of lithium ion from mixed acidic solution with multivalent ions. If this is applied to LIB recycling system, it is expected to reduce CO2 emissions by 30% or more compared to conventional wet refining process.
