Abstract

Background: With the increasing population and decreased quality of drinking water, new materials and methods for the purification of water need to be developed. This study aims to present a solution from pollution by proposing the synthesis method of sodium lauryl sulphate (SLS)-supported thorium (IV) phosphate (ThP), its characterisation and disquisition of analytical applications by executing dual separations of calcium.

Methods: SLS ThP was synthesised by the sol-gel method. The synthesised exchanger was characterised by physicochemical methods, such as powdered X-ray diffraction, scanning electron microscopy, thermo-gravimetric-differential thermal analysis, EDAX and Fourier transform-infrared study. Also, its competency towards the ion exchange processes and in analytical chemistry was verified.

Results: The prominent characteristic of SLS-supported ThP was its high ion exchange capacity for sodium ions (3.10 meq/g), which is almost 2.5 times more than the exchange capacity of ThP, i.e., 1.3 meq/g. The material resulted in a fibrous sheet that is thermally and mechanically stable but poorly crystalline and shows selectivity towards Ca2+ and Hg2+ ions.

Conclusion: The synthesised cation exchange material is thermally stable, showing drastically high exchange capacity and selectivity towards Hg2+ and Ca2+ metal ions, which might be because of the use of an anionic surfactant, SLS, while the synthesis of ThP plays a key role in enhancing the exchange capacity and adsorption of specific metals. Therefore, based on the results obtained, the above-said materials have applications in water purification processes and environmental pollution control where removal of Hg2+ and Ca2+ is essential.

Keywords: Sodium lauryl sulphate, surfactant, surfactant-supported cation exchanger, thorium (IV) phosphate, water purification, water treatment.