The symbiotic effect of integrated Muraya koenigii extract and surface-modified magnetic microspheres – a green biosorbent for the removal of Cu(II) and Cr(VI) ions from aqueous solutions

Abstract

Immobilized magnetic particles are substantially used in several applications, due to their superparamagnetic nature and specific binding capacity with the appropriate support molecules. The present extensive research involves in the synthesis of a robust carrier that integrates the silica-coated amino-functionalized magnetic microspheres with the plant extracts of Muraya koenigii for the removal of both Cu(II) and Cr(VI) pollutants in the wastewater. Analytical techniques include Vibrating Sample Magnetometer (M_s – 9 emu/g) and its saturation magnetization evaluates the superparamagnetic behavior; Fourier transform infrared spectroscopy confirms the existence of functional groups like NH₂, Si-O-Si, C = C; scanning electron microscopy and energy-dispersive X-ray spectroscopy affirms the size of the biosorbent in the range of 300–500 nm and the existence of elements like Fe, N, and Si. The biosorbent shows the maximum adsorption capacity (Cr(VI) – 71.12 mg/g, Cu(II) – 73.71 mg/g). The process follows the pseudo-second-order kinetics and Langmuir isotherm model. The adsorption efficiency (Cr(VI) – 80.07% and Cu(II) – 81.54%) remains stable for nine continuous cycles after regeneration, by treating with 1 N concentrated nitric acid.

Keywords:

• Biosorbent
• Carrier
• Kinetics
• Muraya koenigii
• Magnetic microspheres
• Superparamagnetic

Acknowledgements

Authors are grateful to SSN Trust, India, for financial support.