Novel 3D sphere-like β-In2S3/Biochar nanoflowers for remediation of dyes in single and binary systems and interpretation using statistical physical modeling

Abstract

A novel 3D sphere-like β-In2S3/Biochar nanoflowers have been fabricated through the solvothermal process for effectively removing cationic malachite green and methylene blue dye in both single and binary systems. XRD, SEM, EDX, Elemental Mapping, TEM, BET, XPS, and FT-IR were used to characterize the physical and chemical properties of β-In2S3/Biochar. It was found that MG and MB had an adsorption capacity of 636.94 mg/g and 625.02 mg/g for β-In2S3/Biochar in single systems, while in binary systems, they had an adsorption capacity of 564.97 and 438.58 mg/g, respectively. The adsorption capacities in the multicomponent system were calculated using the extended Langmuir modeling, and the kinetic behavior of the adsorption in both systems followed pseudo-second-order kinetics. From the statistical physical modeling, the nD parameter values for MG adsorption obtained were 0.468, 0.498, and 0.612 at 298, 308, and 318 K, and the nD parameter values for MB adsorption were 0.63, 0.833, and 0.896, respectively in the single systems. These results showed that the dyes were adsorbed in a parallel orientation, and the adsorption followed a multi-interaction mechanism. The effect of water matrices and competing species, such as organic and inorganic compounds, are also investigated to find potential applications in real wastewater. In addition, the decrease in adsorption capacity for both dyes in the binary system was credited to the antagonistic effect, and the high efficiency and reusability of the fabricated β-In2S3/Biochar might provide new ideas for developing competent adsorbents to remove dyes from wastewater.