Combustion synthesis of porous MgO and its adsorption properties

Porous magnesium oxide was synthesized by a combustion method, with Mg(NO3)2, ethylene glycol and deionized water as reactants, and characterized by X-ray difraction, infrared spectroscopy, scanning electron microscopy, transmission electron microscopy and nitrogen sorption/desorption. The results showed that the as-prepared porous magnesium oxide has the multi-scale porous size with a large BET surface area of 203.8 m2 g−1. Magnesium oxides synthesized with other reactants have rod-shaped and granular morphologies, and their BET surface areas are 17.6 and 3.4 m2 g−1, respectively. Compared to the magnesium oxide with the low specifc surface area, porous magnesium oxide exhibited higher adsorption efciency with a maximum adsorption capacity of approximately 1088 mg g−1 in removing Congo red. The as-synthesized porous magnesium oxide could be used as an efcient adsorption material in Congo red removal from the wastewater.