Removal of cadmium ions from wastewaters using corn cobs supporting nano-zero valent iron

The present research article discusses the preparation and characterization of a new magnetic nanocomposite based on corn cobs and nano-zero valent iron (corn cobs-nZVI). The structure of the prepared adsorbent was confirmed by several characterization techniques, such as FT-IR, SEM and XRD. Magnetic measurements approved the magnetic property of the prepared adsorbent. Involvement of the prepared magnetic nanocomposite in the removal of Cd(II) ions from wastewater was investigated. Several parameters, e.g. solution pH, contact time, adsorbent dose, etc., were evaluated and the optimum adsorption conditions were addressed. It was found that a total adsorption capacity of 145 mg/g was achieved at pH 6.0 after 10.0 min of shaking at 25°C. The experimental data were subjected to different isotherm and kinetic models. Moreover, thermodynamic studies were also explored to identify the nature of the adsorption process. The results revealed that the adsorption process follows Langmuir isotherm model with pseudo-second-order kinetic. In addition, it is a spontaneous, exothermic, and irreversible process.