Application of ultrasound-assisted technique for production of mesoporous magnesium oxide from solid waste of ductile iron: An alternative method for elimination of surfactants from precipitation process

Abstract

In the present work, the mesoporous magnesium oxide nanoparticles were produced from the solid waste of ductile iron casting industry. Mg2+ ions were extracted from the waste through the acid leaching, and MgO nanoparticles were obtained by the conventional, and ultrasound-assisted methods. Mg(OH)2 nanoparticles was precipitated in the presence of sodium dodecyl sulfate/Triton, 1:1, and under ultrasound irradiation in the absence of mentioned surfactant. The precipitates were then converted to mesoporous MgO via the calcination at 500 °C. The structure of products was evaluated by X-ray diffractometry (XRD), field emission electron microscopy (FESEM), and N2 adsorption-desorption isotherms. Although MgO nanoparticles with the specific surface area of 118 m2 g−1 could be fabricated by the conventional precipitation, the surfactant concentration should be fixed at the level of 1.5 g L−1. The precipitation under ultrasound irradiation is suggested for the clean fabrication of highly porous powder, 0.7586 cm3 g−1, in which the pore diameter is distributed in the range of 2–12 nm. In consequence, the solid waste of ductile iron industry is a potential material for the fabrication of mesoporous MgO by ultrasound- assisted technique in the absence of surfactant.