Stepwise Thiourea-Based Tungsten Oxide Supported Graphitic Carbon Nitride Preparation: Study of Sulfur-Doped Bulk and Nanosheets g-C3N4/WO3 in Photo Oxidation Degradation of Methylene-Blue Pollution Using Visible Light Radiation

Taguchi model is a model for the analysis of experiments, that predicts both the effects of each factor and the optimum level of them using a certain number of experiments. The purpose of this study was the optimization of Cd(II) ions adsorption on the cobalt oxide using the Taguchi model. The characterization of synthesized cobalt oxide was investigated by Scanning Electron Microscope (SEM), Transmission Electron Microscope (TEM), Fourier Transfer InfraRed (FT-IR) spectrometry and X-Ray Diffraction (XRD). In this experimental study, the cobalt oxide was prepared in a few steps. Then, 4 main factors (i.e. temperature, amount of absorption, contact time, and pH) on 4 levels were selected by Matrix L25 trials and the experiments were conducted in this matrix. Finally, the adsorption of Cd(II) on cobalt oxide was determined in optimal conditions. The optimization of the adsorption process using the Taguchi model showed that the factors of importance for optimizing respectively were: contact time of 20 minutes, pH =8, temperature=15 °Cand adsorbent dosages of 25 mg. The maximum adsorption in optimal conditions was determined 96/21.