Adsorption of copper (II) cation on polysulfone/zeolite blend sheet membrane: Synthesis, characterization, experiments and adsorption modelling

Abstract

Copper-polluted water has a significant impact on environment and cause human health risks. In the present study, a polysulfone/zeolite blend flat sheet membrane was prepared and tailored to adsorb copper ionsfrom aqueous solution. Physiochemical and morphological characteristics of polysulfone/zeolite membrane were analyzed by SEM, EDX and FTIR. Isotherms of the adsorption of copper ion on this membranewere experimentally quantified and analysedat temperatures from 303 to 343 K.Both batch and dynamic adsorption operating conditions were studied to determine themetal removal capability of the membranes. Adsorption study revealed that the metal removal of depended on pH solutionwhere the maximum pH value was 5.0. The highest experimental copper ion adsorption capacity was 101 mg/g. Besides, the dynamic adsorption experiment showed that the polysulfone/zeolite can be utilized to remove copper ions obtaininga high quality of permeate (i.e., <1 mg/L in the treated aqueous solution). This membrane can be used up to fifteen cycles of adsorption without a significant impact on its removal performance. Results obtained from EDX and FTIR studies were employed to describe the potential interaction mechanism between the polysulfone/zeolite membrane and copper ion. It was concluded that this membrane can perform a dual-function for the removal of this metal. To theoretically characterize the adsorption mechanism of this relevant pollutant, a physical model was utilized assuming that the adsorption can be occurred via the interaction with two types of functional groups. This theoretical model was successfully applied on the experimental adsorption data. The number of captured ions by two functional groups, adsorbent performance and adsorption energies were described in the paper to further interpret the adsorption mechanism.