Preparation of new h-MoO3 rod-like microcrystals for effective removal of cationic dye in aqueous solution

Abstract

h-MoO3 rod-like microcrystals were successfully prepared using the hydrothermal microwave method and evaluated as an adsorbent for MB dye’s adsorption from an aqueous medium. The metastable phase with hexagonal structure (h-MoO3) was well confirmed by X-ray diffraction (XRD) and Raman spectroscopy. FE-SEM images of these microcrystals confirm the rod-like morphology for all microcrystals synthesized. The better adjustment of the experimental data in the adsorption kinetics study was adjusted using the pseudo-first-order model, being k1 = 0.0049 min−1, qe,cal = 99.90 mg g−1, and R2 = 0.9975. These microcrystals exhibit a high adsorption rate of MB dye in the pH interval from 4.0 to 11.0. In general, for different temperatures (298 K, 308 K, and 318 K), the experimental data were better adjusted with the Temkin isotherm model, being the process of adsorption was favorable and spontaneous. In addition, the h-MoO3-1 h rod-like microcrystals may be regenerated effectively and reused for adsorption of MB with good adsorption performance at least four times, being promising material in the adsorption of this organic pollutant in aqueous solution.