A survey of Bismuth oxide (BiOI) as an adsorbent in the removal of methylene blue from aqueous solutions

The colored waste from the textile industry is one of the most pollutants in the aquatic environment. One of the most widely used paints in the textile industry is methylene blue, which is often aromatic, often toxic, carcinogenic, mutated and resistant to biological degradation and has harmful effects on living organisms. The purpose of this study was to investigate the bismuth oxyiodide nanoparticles capability to absorb methylene blue from synthetic wastewater. The present study was carried out in a laboratory scale in batch mode. The effects of variables affecting the process including pH, adsorbent dose, contact time and initial concentration of color, kinetic and adsorption isotherm were investigated. The maximum removal efficiency of methylene blue from solutions was observed in optimal conditions as pH of 9, contact time of 30 minutes, absorbance dose of 3 g/L and initial concentration of 10 mg/L. Methylene blue adsorption compliance by BiOI from a pseudo-second kinetic model and Langmuir isotherm model shows that the type of reaction is chemical absorption. The results of the experiments showed that bismuth oxide has a high potential for removal of methylene blue molecules from contaminated wastewater.