Vanadium oxide nanoparticles for methylene blue water remediation: Exploring the effect of physicochemical parameters by process modeling

Vanadium oxide nanoparticles (VO2-NPs) were synthesized and utilized as an adsorbent against methylene blue (MB) from aqueous environment. Three substantial variables, pH, mixing time, and VO2 dose, were considered in the process modeling accomplished by Box-Behnken design (BBD). The quadratic model revealed that the VO2-NPs dose plays the most significant role. The model optimization predicts a 96.3% MB removal when pH, VO2 NPs dosage, and contact time were adjusted to 6, 0.5 g/L, and 30 min, respectively. The sorption capacity of VO2-NPs raised rapidly from 49.6 mg/g to 235.7 mg/g by increasing the initial MB concentration from 25 to 200 mg/L, respectively. The best fitted kinetic model was the pseudo-second order, while the well fitted Langmuir model showed a qmax of 240.5 mg/g. The study of the temperature effect revealed that increase of the temperature had a positive impact on the removal efficiency. [Display omitted] •Vanadium oxide nanoparticles (VO2-NPs) of a high purity and porosity were synthesized.•VO2-NPs revealed an elevated adsorption capability against the methylene blue dye.•The maximum adsorption was estimated as 240.5 mg/g based on the Langmuir model.•Process modeling was accomplished by Box-Behnken design (BBD).•The optimum parameters: pH = 6, 0.5 g/L of adsorbent, and 30 min of mixing