Magnetic hydroxyapatite nanocomposite: Impact on eriochrome black-T removal and antibacterial activity

Abstract

The current investigation reports the removal of Eriochrome Black T (EBT) from aqueous solution by using magnetic hydroxyapatite (M-HAP), a cost-effective adsorbent compared to the other commercial adsorbents. The MHAP nanocomposite was characterized by Fourier transform infrared (FTIR), X-ray diffraction (XRD), Field emission scanning electron microscope (FE-SEM), Environmental scanning electron (E-SEM), BET surface area analyser, vibrating sample magnetometer (VSM) and UV-visible spectrophotometer. The adsorption studies were carried out under different parameters, such as initial dye concentration adsorbent dosage, pH and contact time. An increase in adsorbent dosage along with adecrease in initial dye concentration would cause an increase in the removal of EBT. The maximum adsorption occurred at pH 7.0. The optimum conditions of initial dye concentration 30 ppm and adsorbent dosage are 100 mg. The kinetic data were analyzed using pseudo-first order and pseudo-second order equation. Kinetically, the pseudo-second ordershows best fit (R-2 = 0.99), indicating the adsorption process follows chemisorption's. The Langmuir isotherm model were obtained best fit with high correlation coefficient (R-2 = 0.99), which implies that the adsorption of EBT dye onto M-HAP is monolayer with maximum adsorption capacity (q(max))is 43.47 (mg/g).The M-HAP nanocomposite was also further examined for its antibacterial activities against Escherichia coli (E. coli) and Micrococcus luteus (M. luteus) strain. These result exhibit the vast scope of M-HAP in water remediation for both dye removal and antibacterial activity. (C) 2019 Elsevier B.V. All rights reserved.