Moringa oleifera gum composite a novel material for heavy metals removal

ABSTRACT

In this study, composite coagulant prepared by using Moringa oleifera gum with bentonite clay of non-toxic nature was named as coagulo-adsorbents. They are for removing the heavy metals from the aqueous systems used for drinking-water purposes. The method adopted in this study is heavy metals removal by coagulo-adsorption and double filtration processes. Clay-polymer nanocomposites were successfully prepared by solution processing method using bentonite clay and biodegradable polymer of Moringa oleifera gum and their structures were characterised by Fourier transform infrared spectroscopy (FTIR) techniques, Powder X-ray diffraction (P-XRD), scanning electron microscopy (SEM) and Transmission electron microscopy (TEM). The FTIR shows the functional group variations of the coagulants such as clay, biopolymer and their composites. The XRD results revealed the information on the degree of the hybrid structure generated and crystal size of the clay, polymer and composites. The surface topography and shapes of clay, polymer and composites were studied by SEM and TEM. In all cases, the clay-polymer composite of Moringa oleifera gum and bentonite clay showed considerable cadmium, chromium and lead removal property. The results indicate that clay-polymer composites of MO gum and bentonite clay have a greater potential for removing metal ions (up to 100% reduction). Thus, this study is the first report of removal of heavy metals by a clay-polymer composite of Moringa oleifera and bentonite.

KEYWORDS:

• Hazardous heavy metals
• clay-polymer nanocomposite
• coagulo-adsorption cadmium removal
• chromium removal
• lead removal

Acknowledgments

The authors thank the Founder Director Late. Dr. P. K. K. Nair, President Dr. G. Madhavan Nair, Director Dr. G. Achuthan Nair and Principal Scientist & Deputy Director Dr. Shaji P.K of Environmental Resources Research Centre (ERRC), Thiruvananthapuram for the constant support rendered during the course of this research work.

Disclosure statement

No potential conflict of interest was reported by the authors.

Additional information

Funding

This research did not receive any specific grant from funding agencies in the public, commercial, or not-for-profit sectors.