Preparation of Mesoporous Silica from Electrolytic Manganese Slags by Using Amino-Ended Hyperbranched Polyamide as Template

Large quantities of waste slags are produced during the preparation of electrical manganese, causing serious pollution to the environment. The recycling and utilization of electrolytic manganese slag (EMS) is a serious challenge to the industry. Here, we report the utilization of EMS in preparation of high-performance mesoporous silica using amino-ended hyperbranched polyamide (AEHPA) as template. The effects of AEHPA content and molecular weight on properties of mesoporous silica, including the specific surface area, pore diameter, pore volume, size, and distribution, have been investigated. On the basis of 0.3 wt % AEHPA-2 during the preparation of silica, the specific surface area, pore volume, and pore diameter of the produced amorphous mesoporous silica are 451.34 m(2) g(-1), 0.824 cm(3) g(-1), and 7.09 nm, respectively, showing remarkable improvements over the silica without AEHPA in specific surface area (271.05 m(2) g(-1)), pore volume (1.167 cm(3) g(-1)), and pore diameter (17.43 nm). The formation mechanism of mesoporous silica has been supposed and substantiated by FT-IR, XRD, XPS spectra, and SEM micrographs. This preparation method of mesoporous silica from EMS may open a new avenue for recycling and utilization of manganese slag.