Sonochemically Prepared BSA Microspheres as Adsorbents for the Removal of Organic Pollutants from Water

This work investigates, for the first time, the application of sonochemically prepared bovine serum albumin (BSA) microspheres (BSAMS) as adsorbents of industrial organic pollutant dyes, such as rhodamine B (RhB), rhodamine 6G (Rh6G), and methylene blue (MB). These dyes also serve as model compounds for other organic pollutants such as bisphenol A and 2-nitrophenol. Adsorption kinetics of the dyes by the BSAMS was studied using pseudo-first-order (PFO) and pseudo-second-order (PSO) kinetic models. It was found that RhB follows PFO, with an adsorption capacity, q(e,cal), of 7.9 mg/g, which was closer to the experimental adsorption capacity of q(e,exp) of 7.6 mg/g. However, MB and Rh6G were controlled by PSO kinetics, with a q(e,cal) of 5.6 mg/g for MB and 6.6 mg/g for Rh6G, closer to the experimental adsorption capacity of 5.7 and 6.4 mg/g, respectively. The intraparticle diffusion (ID) model applied to the three dyes indicated multi-linearity with ID as the rate-limiting step in the adsorption process. Furthermore, the adsorption equilibria for each of the organic pollutants were studied through various isotherm models such as Langmuir, Freundlich, Temkin, and Halsey, which indicated physical interaction between the BSAMS and the dye pollutants, thus suggesting the applicability of the BSAMS as pollutant adsorbent materials. It was found that the BSAMS can effectively remove RhB, MB, and Rh6G from wastewater with efficiencies of 95.5, 83.3, and 97.9%, respectively.

Automated summary

This study investigates the application of sonochemically prepared bovine serum albumin microspheres as adsorbents for industrial organic pollutant dyes, showing high efficiency in removing RhB, MB, and Rh6G from wastewater. The adsorption kinetics and equilibrium of the dyes were studied using various models, suggesting physical interaction between the microspheres and the dye pollutants. The results highlight the potential of bovine serum albumin microspheres as effective pollutant adsorbent materials.