Functionalization of β-cyclodextrin onto NiFe<inf>2</inf>O<inf>4</inf> nanoparticles for the removal of ketoprofen and diclofenac from the aqueous solutions

Abstract

A new β-CD functionalized nickel ferrite nanocomposite was synthesized and used to remove pharmaceutical drugs, such as ketoprofen (KF) and diclofenac (DCF). The co-precipitation approach was utilised to synthesize nickel ferrite (NFO) nanoparticles, which were then functionalized with TEOS to form NFO@SiO2; β-cyclodextrin was then functionalized using GPTMS as an interface to form NFO@SiO2@β-CD. FTIR, ZD, FE-SEM, EDX, TGA/DTG, VSM, BET, zeta potential and particle size analysis were then used to characterise the nanocomposites. The NFO@SiO2@β-CD has an average diameter of 109.1 nm, superparamagnetic behaviour, a mesoporous surface and a specific surface of 20.78 m2/g. The functionalized NFO@SiO2@ β-CD nanocomposite removed 94% of diclofenac in 5 min and 80% of ketoprofen in 360 min with the adsorption capacities of 8.46 and 0.54 mg/g, respectively. The obtained experimental datum for both the pollutants was fitted in kinetic and isotherm models, with the pseudo-second-order kinetic model and Freundlich adsorption isotherm showing the best fit with the highest regression of R 2 = 0.99. The nanocomposite was regenerated using 0.1 M NaOH and recycled for about four consecutive cycles in which the reduction in the removal efficiency of ketoprofen and diclofenac was observed to be 51.36% and 64%, respectively. These results suggested that the NFO@SiO2@β-CD nanocomposite could be used specifically to target the low-concentrated pharmaceutical pollutants. Graphical Abstract: Schematic representation of Functionalization of β-Cyclodextrin onto NiFe2O4 nanoparticles for the removal of ketoprofen and diclofenac from the aqueous solutions. [Figure not available: see fulltext.]