Acidic Amorphous Silica Prepared from Iron Oxide of Bacterial Origin

摘要: Microporous and mesoporous silica derived from biogenous iron oxide is an attractive catalyst for various organic reactions. Biogenous contains structural silicon, amorphous remains after dissolved in concentrated hydrochloric acid. The containing slight amounts of (Si/Fe = ∼150) composed ∼6-nm-diameter granular particles. has a large surface area 540 m2/g with micropores (1.4 nm) mesopores (<3 nm). By using pyridine vapor as probe molecule to evaluate the active sites silica, it was found that this material strong Bronsted Lewis acid sites. When catalytic performance evaluated reactions including ring opening epoxides Friedel–Crafts-type alkylations, which are known be catalyzed by catalysts, showed yields higher than those obtained common materials.