Sulfur removal from municipal gas using magnesium oxides and a magnesium oxide/silicon dioxide composite

Magnesium oxides (MgOs) were synthesized by polyol-meditation thermolysis, hydrothermal, and aerogel methods and utilized to remove sulfur compounds from municipal gas. The capacity to remove methyl mercaptan (291 μmol/mol) from methane was evaluated by using an adsorption breakthrough method at different temperatures. Then, to improve the sulfur removal capacity, a MgO-SiO ₂ composite was developed using the aerogel method and its breakthrough capacity was compared to those of the MgOs. The synthesized MgOs and MgO-SiO₂ composite were characterized by XRD, BET, TGA, and HR-TEM. The MgO prepared by the aerogel method had the highest surface area and sorption capacity among the as-synthesized MgOs. Furthermore, the sulfur sorption capacity of the MgO-SiO₂ composite prepared by the same aerogel method as MgO was three times higher than the aerogel MgO even though the sorption capacity of SiO₂ was negligible.