Calcination temperature plays a crucial role in determining the surface properties of generated MgO, but the influence of temperature variation in a muffle furnace during calcination on its performance is rarely repor...Calcination temperature plays a crucial role in determining the surface properties of generated MgO, but the influence of temperature variation in a muffle furnace during calcination on its performance is rarely reported. Herein we observed that the temperature in a muffle furnace during calcination demonstrated a gradually increasing trend as the location changed from the furnace doorway to the most inner position. The variation in temperature had a great impact on the adsorption performance of generated rod-like MgO without and/or with involvement of Na2SiO3 to Congo red in aqueous solution. To get a better understanding on the detailed reasons, various techniques including actual temperature measurement via multimeter, N2 physical adsorption, CO2 chemical adsorption and FT-IR spectrometry have been employed to probe the correlation between the adsorption performance of generated MgO from various locations and the inner actual temperature of used muffle furnace as well as their physicochemical properties. In addition, two mechanisms were proposed to elucidate the adsorption process of Congo red over the surface of generated MgO without and/or with presence of Na2SiO3, respectively.展开更多
基金The authors would like to acknowledge funding support from the National Natural Science Foundation of China （Grant Nos. 21575112, 21777128 and 21705125） and Shaanxi S＆T Research Development Project of China （Grant No. 2016GY-231）.
文摘Calcination temperature plays a crucial role in determining the surface properties of generated MgO, but the influence of temperature variation in a muffle furnace during calcination on its performance is rarely reported. Herein we observed that the temperature in a muffle furnace during calcination demonstrated a gradually increasing trend as the location changed from the furnace doorway to the most inner position. The variation in temperature had a great impact on the adsorption performance of generated rod-like MgO without and/or with involvement of Na2SiO3 to Congo red in aqueous solution. To get a better understanding on the detailed reasons, various techniques including actual temperature measurement via multimeter, N2 physical adsorption, CO2 chemical adsorption and FT-IR spectrometry have been employed to probe the correlation between the adsorption performance of generated MgO from various locations and the inner actual temperature of used muffle furnace as well as their physicochemical properties. In addition, two mechanisms were proposed to elucidate the adsorption process of Congo red over the surface of generated MgO without and/or with presence of Na2SiO3, respectively.
