Polypropylene–zeolite polymer composites for water purification: synthesis, characterisation and application

Abstract

This paper reports on the preparation of polypropylene–zeolite polymer composites using the melt-mixing compounding technique. These polymer composites have shown unique and enhanced properties as compared to their monolithic constituents. All polymer hybrids were formed by solvent-less melt-intercalation and extrusion. The changes in conventional properties of the two mixed constituents were probed using techniques, such as scanning electron microscopy, X-ray diffraction (XRD), Fourier transform infrared spectroscopy and thermogravimetric analysis. XRD analyses showed a co-existence of intercalated and exfoliated zeolite phases. The influence of operational conditions such as exposure time, zeolite loading rate and solution pH were determined. An optimum zeolite loading of 15 wt.% was observed. Solution pH had the greatest influence on the removal of both heavy metals and substituted phenols. The polymer composites exhibited both adsorption and ion-exchange properties in the removal of heavy metals in aqueous media.

Keywords:

• Adsorption
• Characterisation
• Composites
• Polypropylene
• Zeolite

Acknowledgements

Funding for this project was obtained from the DST/Mintek Nanotechnology Innovation Centre (NIC) and the University of Johannesburg (UJ).