Utilisation of adsorption/photocatalytic method for efficient removal of acid orange 8 dye from aqueous media using a novel hydrogel/Fe₂O₃ composite

ABSTRACT

In this work, a novel hydrogel⁄Fe₂O₃ composite was synthesized using the microwave-induced copolymerization/sol-gel method. The synthesised hydrogel⁄Fe₂O₃ composite was characterised by many instruments as FT-IR, XRD, FE-SEM, CHN elemental analysis, and UV-Vis spectrophotometer. The broad peak in the XRD pattern confirms the amorphous structure of the synthesised hydrogel⁄Fe₂O₃ composite. The diffraction peaks at 2ϴ = 26.92°, 23.50°, and 12.80°, indexed as (013), (130), and (021), respectively confirm the presence of crystalline sheets of chitin. The presence of a peak at 2ϴ = 16.73° (154) was observed because of the presence of polyacrylamide. The synthesised hydrogel⁄Fe₂O₃ composite was used for the removal of acid orange 8 dye from aqueous media by the adsorption/photocatalytic method. The % removal (% R) increases with an increase in time from 5 min (% R = 14) to 25 min (% R = 52), and after that, approximate stability occurs. In the case of the presence of hydrogen peroxide and hydrogel⁄Fe₂O₃ composite, the % degradation (% D) under UV irradiations increases with an increase in irradiation time from 10 min (% D = 37.50) to 50 min (% D = 100). The first order is the suitable kinetic model for the description of adsorption and photocatalytic processes.

KEYWORDS:

• Hydrogel⁄Fe₂o₃ composite
• adsorption
• photocatalytic degradation
• acid orange 8 dye

Acknowledgments

This Research was funded by The Deanship of Scientific Research at Princess Nourah Bint Abdulrahman University through the Fast-Track Research Funding Program.

Disclosure of potential conflicts of interest

No potential conflict of interest was reported by the author(s).