Journal of Chemical Engineering of Japan, Vol.41, No.11, 1042-1048, 2008
Effect of Pore Widening Treatment on BET Surface Area of Rapidly Anodized Alumina Support
In this study, to reduce the preparation time and production cost of anodic alumina support, the rapid anodization in sulfuric acid solution and at a high electric current density was employed to synthesize the rapidly anodized alumina support. After rapid anodization, the alumina support was soaked in sulfuric acid solution to widen its pore size (pore widening treatment, PWT). PWT conducted at 293-298 K for 45-60 min in 15.0 wt% sulfuric acid solution is considered to be effective to widen pore radius. PWT slightly changed its BET surface area, but it caused a substantial increase in BET surface area after subsequent HWT (hot water treatment) and high-temperature calcination. It is believed that PWT that it effectively reduces the inhibitory pore-sealing effect caused by HWT, and allows more alumina to react with hot water to form hydrated alumina, and obviously eventually increases its BET surface area.
Keywords:Anodic Alumina Support;Rapid Anodization;Sulfuric Acid;Pore Widening Treatment;BET Surface Area