Nanostructured Membrane of Sodium Montmorillonite Reinforced Cellulose Acetate for Adsorption of Ca(II) and Mg(II) Ions in Hard Water

Abstract:

Permanent hard water softening was conducted with the use of cellulose acetate (CA)/sodium montmorillonite (Na⁺-MMT) nanostructured membranes. Fabrication of the nanostructured membranes with various Na⁺-MMT loading (0%, 5%, 10%, 15%) was made possible by electrospinning technique, which was carried out at 25°C, 30 kV applied voltage, needle size of 25G and a tip to collector distance of 18 cm. The effect of Na⁺-MMT content on the morphology of the fiber was examined with the use of Scanning Electron Microscope (SEM). It was determined that increasing the Na⁺-MMT loading decreases the average fiber diameter. The molecular structure of the blend nanostructured membranes were investigated using Fourier Transform Infrared (FTIR) Spectroscopy and the existence of CA and Na⁺-MMT in the electrospun nanostructured membrane was confirmed. Better adsorption performance was observed for the blend with 15% Na⁺-MMT as compared to pure CA and maximum uptake rate was attained at 7 hours for pure CA and only 5 hours for CA/Na⁺-MMT (85%/15%) blend. Increasing the initial hard water concentration increases the driving force for diffusion and in turn increases adsorption capacity of both pure CA and the CA/Na⁺-MMT (85%/15%) blend. More so, the results of the experiment best fitted the pseudo-second order kinetic model and the Freundlich isotherm model. Integration of Na⁺-MMT in CA increases the surface area for adsorption of the nanostructured membrane, and thus, could be used as an effective adsorbent for hard water softening.

• Periodical: Key Engineering Materials (Volume 801)
• Pages: 319-324
• DOI: https://doi.org/10.4028/www.scientific.net/KEM.801.319
• Online since: May 2019
• Authors: Ruth R. Aquino*, Marvin S. Tolentino, Diana Jean C. Ramolete, Arra M. Calingasan, Minerhiza N. Dela Cruz, Blessie A. Basilia
• Keywords: Cellulose Acetate, Electrospinning, Hard Water Softening, Sodium Montmorillonite

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