Investigation of the Effect of Using Iron Oxide Nanoparticles in Removing Cadmium from Aqueous Media: A Laboratory Study

Cadmium is a heavy metal, which has high toxicity and high accumulation properties in living tissue. The purpose of this study was to determine the efficiency of iron oxide nanoparticles in the adsorption of cadmium from aqueous media.

This laboratory study was performed in the summer of 2018. XRD (X-ray powder diffraction)  and SEM (scanning electron microscope) were used to characterize the adsorbent properties and FTIR (fourier-transform infrared spectroscopy) analysis was performed to investigate the adsorbent functional groups.Various factors in cadmium  removal were investigated such as pH, cadmium concentration, contact time and adsorbent dose. Langmuir and Freundlich absorption isotherms were used to describe absorption data. For data processing, a completely randomized block design was used.

Adsorption rate was fixed after 20 minutes (61%, p=0.032). The highest adsorption was achieved at pH=7 (99%, p=0.043) and the lowest adsorption was observed with a significant difference at pH=3 (68%, p=0.048). The adsorption rate of metal, significantly different compared to the others, was the most in the concentration of 20 mg / L and the lowest in the concentration of 90 mg / L (97% and 70.5%, p=0.039). In relation to the effect of iron oxide adsorption, the highest adsorption was observed at 2 grams per liter and the lowest adsorption percentage was at 0.5 grams per liter (97.96% and 75%, p=0.047). The adsorption of cadmium by iron oxide was consistent with the Langmuir model (R2=0.4888).

According to the results, it is recommended to use nanoparticle coatings to increase the cadmium uptake efficiency, and it can be considered as an effective way to remove cadmium.