Optimization of ecofriendly L-Fe/Ni nanoparticles prepared using extract of black tea leaves for removal of tetracycline antibiotics from groundwater by response surface methodology

Abstract

This article focuses on employment of nanotechnologies in remediation of tetracycline antibiotics (TC) from groundwater by green synthesized bimetallic Fe/Ni supported by limestone particles. An in-situ green synthesis nanoparticles was prepared using black tea leaves extract to generate a L-Fe/Ni nanocomposite. The synthesized nanocomposite was characterized using several techniques, such as, X-Ray Diffraction (XRD), Scanning Electron microscopy (SEM), transmission electron microscope (TEM), Energy dispersive X-ray (EDX), FTIR (Fourier Transform-Infra Red) spectroscopy and surface area. We then use response surface methodology (RSM) to optimize the synthesis process and evaluate the effectiveness of the prepared nanocomposite for tetracycline remediation. We took different simulated concentrations of the TC contaminant without relying on actual TC concentrations in grounwater, the best removal of the TC contaminant in batch study was investigated with relying on the initial concentrations of TC and other experimental factors such as pH, adsorbent nanomaterial concentration and time. A pilot plant was then constructed to eliminate the TC contaminant from groundwater in different concentrations, where the removal efficiency was found decreased with increasing in the concentration of the TC Many parameters affecting the removal mechanisms in statistical and continuous systems were examined to select the best results that accomplish the maximum elimination rate. With the improved operating conditions, (L-Fe/Ni concentration: 1500 mg/L; concentration of TC: 20 mg/L; pH: 7.2; contact time: 128 min), removal percent of TC was found 87 % based on RSM system. The L-Fe/Ni reactive medium of continuous column has a main role in slowing down the movement of the TC plume. This study showed that the ecofriendly nanocomposite could be an appropriate and novel method for remediation of antibiotics and other contaminants in groundwater.