Comparison between removal of Ethidium bromide and eosin by synthesized manganese (II) doped zinc (II) sulphide nanoparticles: kinetic, isotherms and thermodynamic studies.

The present work seeks to investigate the kinetics and thermodynamic studies of ethidium bromide (EtBr) and eosin adsorption onto the synthesized Manganese (II) doped Zinc (II) Sulphide nanoparticles. A convenient scheme of co-precipitation was used for the synthesis of Manganese (II) doped Zinc (II) Sulphide nanoparticles. The Fourier transform infrared spectroscopy (FTIR), field emission scanning electron microscopy (FESEM) and X-ray diffractogram (XRD) techniques were used for the characterization of synthesized nanoparticles. The adsorption study was undertaken in a systematic manner. Effects of different experimental parameters were studied using batch adsorption method. It was evident from the results that EtBr and eosin removal was inversely proportional to the concentration of initial dye and directly proportional to contact time and adsorbent used. To study the adsorption equilibrium three different isotherm models like Langmuir, Freundlich and Flory-Huggins were used. It was observed that adsorption data synced most successfully with Langmuir isotherm model as compared to Freundlich and Flory-Huggins isotherm model. To fit the investigational statistics, the kinetic models pseudo 1st order, pseudo 2nd order and intra particle diffusion were taken onto consideration. The maximum dye removal of 98.19% and 97.16% for EtBr and eosin, was observed during the synthesis of nanoparticles. © Springer Nature Switzerland AG 2020.