Aminated reduced graphene oxide-CuFe ₂ O ₄ nanohybride adsorbent for efficient removal of imidacloprid pesticide

Abstract

To remove organic and inorganic agrochemicals from contaminated soil and water, adsorption has been regarded as a viable remediation approach. For the removal of organic pollutants, such as pesticides, cost-effective adsorbents have garnered a lot of interest. These include waste-derived materials, clay composites, metal-organic frameworks (MOFs), nanocomposites, and biochar-modified materials. In this study, copper ferrite (CuFe₂O₄) was prepared, characterized, and modified with aminated reduced graphene oxide (Am-rGO) to form a CuFe₂O₄/Am-rGO nanocomposite for the effective removal of imidacloprid (IMD) from water. The Langmuir isotherm model was used to determine the maximum adsorption capacity of the adsorbent (CuFe₂O₄/Am-rGO), which was estimated to be 13.1 (±1.5) mg g^-1. At 0.5 mg L^-1 IMD, the adsorbents were able to extract up to 97.8% of the IMD from the aqueous solution. The Freundlich model and the pseudo second-order model agreed well with the experimental data, proving that physisorption and chemosorption both played a role in the sorption process. CuFe₂O₄/Am-rGO nanocomposite offers high stability and improved reusability due to its improved removal efficiency. After five adsorption-desorption cycles, there was no appreciable reduction in elimination. Additionally, after adsorption tests, IMD can be easily removed after adsorption by an external magnetic field. These showed that Am-rGO had changed the surface of CuFe₂O₄ to make it easier for IMD to stick to it in aqueous solutions. When used adsorbent is co-processed with ethanol extraction and ultrasound cavitation, it can be regenerated and still work well as an adsorbent. Furthermore, CuFe₂O₄/Am-rGO demonstrated its environmental safety and ability to continue absorbing IMD across a variety of diverse matrices. As a result, this study demonstrates that CuFe₂O₄/Am-rGO is a long-lasting, easily prepared, and efficient adsorbent for the removal of IMD as one of the neonicotinoids.