Pt nanoparticles decorated WO3-MWCNTs nanocomposites: Preparation, characterization, and adsorption behavior

A novel multi-walled carbon nanotubes-WO3-Pt nanocomposite (Pt-WO3-MWCNTs) was synthesized using a simple facile two-step precipitation method. Several analytical techniques such as X-ray diffraction, field-emission scanning electron microscopy, transmission electron microscopy, were used for the surface characterization of the synthesized nanocomposites and the specific surface area of the synthesized nanocomposites i.e. WO3MWCNTs and Pt-WO3-MWCNTs using BET method was found to be 24.31 and 37.81 m(2)/g respectively. Effective parameters such as pH, reaction time, temperature, and initial concentrations which plays a significant role in adsorption phenomenon of typical hazardous pharmaceutical waste on Pt-WO3-MWCNTs was optimized using the batch adsorption experiments and the optimized values of pH, and contact time is 5, and 1 h respectively. It was observed that the warfarin uptake decreases from 141.2 mg/g to 121.1 mg/g as the solution pH increases from 5 to 9. Non-linear regression method was adopted to analyze the obtained equilibrium data in terms of Langmuir, Freundlich, and Temkin models. The Langmuir isotherm fitted the equilibrium data best among the four models, and the adsorption capacity increased with the temperature increased from 5 degrees C to 35 degrees C. Hence, Pt-WO3-MWCNTs could be used as an efficient adsorbent for adsorption of warfarin. (C) 2016 Elsevier B.V. All rights reserved.