Isothermal models of Chromium (VI) adsorption by using Fe3O4 nanoparticles

The ferromagnetic Fe3O4 nanoparticles with the average particle size of about 10 nm were used to adsorb chromium (VI) in aqueous solution. The equilibrium of Cr(VI) adsorption can be achieved at the pH value of 2.5, in the contact time of 120 minutes. The mechanisms of Cr(VI) adsorption were evaluated by 4 isothermal adsorption models Langmuir, Freundlich, Redlich-Peterson, and Temkin. The results showed that all four models are satisfied; especially, Redlich-Peterson is the most suitable model to describe the adsorption kinetic of Cr(VI) on ferromagnetic Fe3O4 nanoparticles

FTIR Combined with Chemometrics for Fast Simultaneous Determination of Penicillin and Cephalexin in Pharmaceutical Tablets

In this research, the potential of combining chemometrics with FTIR techniques to provide a rapid and simultaneous quantitative analyses method for determination penicillin, cephalexin is studied. Unlike other methods, FTIR is considered as a time saving method due to its non-destructive and simple sample preparation. Due to the similarity of infrared spectral, PLS and PCR couples with spectral treatment techniques are applied to make the calibration model for penicillin and cephalexin determination at the same time. The result is also validated in term of RMSEP and R2 value using validation set. The FTIR combined with PLS method shows the best results