Graphene-loaded sodium alginate nanocomposite membranes with enhanced isopropanol dehydration performance via a pervaporation technique

Abstract

Graphene-loaded sodium alginate (NaAlg) nanocomposite membranes have been prepared to enhance the pervaporation (PV) dehydration of isopropanol. The effect of graphene loading on the physico-chemical properties, micro-morphology and barrier performance of the derived nanocomposite membranes was investigated as a function of temperature and feed water composition of the isopropanol mixture. The interaction of graphene with the NaAlg matrix as well as water and isopropanol seems to influence the thermal, kinetic and Arrhenius activation energy parameters. At the lowest concentration of graphene, the membrane performance was optimum with a permeance value of 3122 GPU and a selectivity of 4623 for a 10 wt.% water containing feed mixture at 30 °C. Flory–Huggins theory could explain the polymer–solvent interaction as well as equilibrium swelling; both of these affected the membrane performance.