Fast adsorptive removal of direct blue-53 dye on rare-earth doped Lanthanum aluminate nanoparticles: equilibrium and kinetic studies

The nanocrystalline LaAlO3: Sm3+: Bi3+ composites are synthesized using sugar as fuel through the solution combustion process. Prepared composites were well categorized by Powder Xray Diffraction (PXRD), Scanning Electron Microscopy (SEM), Transmission Electron Microscopy (TEM), UV-Visible spectroscopy, Fourier Infrared Transform (FTIR) spectroscopy, Brunauer-Emmett-Teller (BET) analysis. The average size of the crystallites as estimated using Scherrer equation is in the range 30-46 nm agreeing with TEM results. The SEM images show the spherical agglomerated nanoparticles. The nominal composition of dopant and co-dopant ions present inside the host lattice is confirmed with EDX patterns. The adsorption of Direct Blue-53 (DB-53) dye has been investigated. The influence of adsorbent load, the concentration of dye, pH and time on adsorption of Direct Blue-53 dye was studied. The statistical error computation and nonlinear curve fitting of experimental isotherm and kinetic data are carried out using Excel solver-2019 (Microsoft office-2019 USA). The kinetic studies indicate that the adsorption process follows pseudo first-order kinetics and isotherm studies suggest that the Dubinin-Radushkevich (D-R) isotherm model is well fitted and is in good agreement with experimental data. The adsorbent is admirable and promising in the adsorption capacity and is beneficial in the elimination of toxic and non-biodegradable organic pollutants in water.