BaCO3 nanoparticles (NPs) (20 and 100 nm) were prepared using poly(vinyl pyrrolidone) (PVP) as stabilizer. The prepared NPs showed high adsorption capacity for Mg2+ in presence of other cations (Na+, Ca2+ etc.). BaCO3 nanoparticles embedded sulphonated poly(ether sulfone) (SPS) membranes were prepared, which showed Mg2+ retentive and cation selective properties. These membranes exhibited good thermal, mechanical, and chemical stabilities along with conductivity and ion-exchange capacity due to SPS matrix. Mg2+ retentive nature of these membranes was attributed to the embedded BaCO3 NPs. Further, SPS-NPE membrane was assessed suitable for electro-separation process. Electrodialytic studies confirmed very high retention values for Mg2+ in comparison with Na+ and Ca2+. The energy consumption of proposed process suggested suitability of these membranes for separation/recovery of Mg2+ from natural water resources. (C) 2014 Elsevier B.V. All rights reserved.