Hydrothermal synthesis and characterization of ordered mesoporous magnesium silicate-silica for dyes adsorption

• Hydrothermal synthesis of meso-MgSiO-SiO using C@SBA-15.
• C@SBA-15 plays both assisted template and silicon source.
• Meso-MgSiO-SiO shows superior adsorption property for dyes.

Mesoporous materials with substantial specificities have potential applications in pollutant adsorption. In this work, ordered mesoporous magnesium silicate-silica was prepared by a facile hydrothermal method using mesoporous silica SBA-15 filled with carbon (C@SBA-15) as both assisted template and silicon source. During hydrothermal process, the carbon inside the pores of the SBA-15 supported magnesium silicate as mesoporous wall. The magnesium silicate together with the remainder silica exhibited ordered mesoporous structure, BET surface area of 432 m2/g, and bimodal pore size distributions. The mean pore sizes were 5.46 and 55.0 nm. The ordered mesoporous magnesium silicate-silica showed a fast adsorption rate for methylene blue; meanwhile, the adsorption capacities for methylene blue and Rhodamin B were 283 and 227 mg/g, respectively.