Preparation, characterization and application of synthesized nano Zn(OH)8Cl2H2O in removing of dye pollutants: Modeling of removal process by response surface methodology

Zinc hydroxide chloride nanostructure was successfully synthesized through a simple method at low temperature by sonochemical process. The morphology and crystalline of the products were examined by X-ray diffraction (XRD) analysis, Field emission scanning electron microscopy (FESEM) and transmission electron microscopy (TEM). Response surface methodology was used to optimize the Reactive Yellow 145 dyes dye adsorption onto zinc hydroxide chloride nanostructure. The effect of independent variables including contact time, solution pH, adsorbent dosage and the concentration of dye on removal performance was investigated based on Central Composite Designs. ANOVA was applied to analyze the responses. Maximum removal was achieved about 52.11% at following conditions: dye concentration = 40 mg/l; pH = 4; dosage = 0.02 g/50 ml; time = 80 min. Investigating the isotherm and kinetic models showed that the experimental data were correlated with Temkin adsorption isotherm and pseudo-second order kinetic models.