This project has received funding from the European Union's Horizon 2020 research and innovation programme under grant agreement No 869467 (SEArcularMINE). This work was supported by the Associate Laboratory for Green Chemistry- LAQV, which is financed by Portuguese national funds from FCT/MCTES (UID/QUI/50006/2019). This work was also supported by "Programa Operacional Regional de Lisboa, na componente FEDER" and "Fundacao para a Ciencia e Tecnologia, I.P." through research project PTDC/EQU-EPQ/29579/2017. S. Pawlowski acknowledges Fundacao para a Ciencia e Tecnologia, I.P. for his contracts CEECIND/01617/2017 and CEECIND/00340/2018. iNOVA4Health – UIDB/Multi/04462/2020, a program financially supported by Fundacao para a Ciencia e Tecnologia is acknowledged. Funding from INTERFACE Programme, through the Innovation, Technology and Circular Economy Fund (FITEC), is also gratefully acknowledged. The authors acknowledge Professor Vítor D. Alves, from Instituto Superior de Agronomia, Universidade de Lisboa, for the support to analysing mechanical properties.

Dataset of paper entitled "Development of highly selective composite polymeric membranes for Li+/ Mg2+ separation" published at Journal of Membrane Science 620 (2021) 118891.