Preparation, characterization of titanate nanosheet–pozzolan nanocomposite and its use as an adsorbent for removal of diclofenac from simulated hospital effluents

Abstract

Abstract The nanocomposite titanate nanosheet–pozzolan (TNS–PZ) was prepared by the alkaline hydrothermal process using titanium (IV) isopropoxide solution as titanium precursors at different concentrations. The characterization of the material was obtained by, Diffuse Reflectance UV–vis analysis (DRUV), X-ray diffraction (XRD), Energy-dispersive X-Ray spectroscopy, Fourier transform Infrared Spectroscopy (FTIR), scanning electron microscopy (SEM), transmission electron microscopy (TEM), and nitrogen adsorption/desorption isotherms. The adsorbent material was used for successful removal of the anti-inflammatory diclofenac (DFC) from aqueous solutions. The kinetic data were better fitted to nonlinear general order kinetic model, based on the Bayesian Information Criterion (BIC). The equilibrium isotherms also were obtained employing the nonlinear method and based on the BIC; the best isotherm model was the Liu. Based on the Liu isotherm model, the maximum sorption capacity (Qmax) of DCF onto the TNS–PZ adsorbent was 90.52\u202fmg\xa0g−1 at 10\u202f°C. The thermodynamic parameters of adsorption were calculated, and the adsorption process was spontaneous, exothermic, and the magnitude of changes in enthalpy, are consistent with physical adsorption of DCF onto TNS–PZ. Also, the adsorbent was tested for simulated hospital effluents, and it was able to remove up to 96.50% of the effluents.