Silicalite

Silicalite is an inorganic compound with the formula SiO 2 . It is one of several forms (polymorphs) of silicon dioxide. It is a white solid. It consists of tetrahedral silicon centers and two-coordinate oxides. It is prepared by hydrothermal reaction using tetrapropylammonium hydroxide followed by calcining to remove residual ammonium salts. The compound is notable in being ca. 33% porous. It is useful because the material contains (SiO) 10 rings that allow sorption of hydrophobic molecules of diameter 0.6 nm. A commercially important modification of silicalite is titanium silicalite. With the formula Si 1−x Ti x O 2 , it consists of silicalite with Ti doped into some Si sites. Unlike conventional polymorphs of titanium dioxide, the Ti centers in titanium silicalite have tetrahedral coordination geometry. The material is a useful catalyst for the reaction of hydrogen peroxide with propylene to give propylene oxide.

Silicalite is an inorganic compound with the formula SiO 2 . It is one of several forms (polymorphs) of silicon dioxide. It is a white solid. It consists of tetrahedral silicon centers and two-coordinate oxides. It is prepared by hydrothermal reaction using tetrapropylammonium hydroxide followed by calcining to remove residual ammonium salts. The compound is notable in being ca. 33% porous. It is useful because the material contains (SiO) 10 rings that allow sorption of hydrophobic molecules of diameter 0.6 nm. A commercially important modification of silicalite is titanium silicalite. With the formula Si 1−x Ti x O 2 , it consists of silicalite with Ti doped into some Si sites. Unlike conventional polymorphs of titanium dioxide, the Ti centers in titanium silicalite have tetrahedral coordination geometry. The material is a useful catalyst for the reaction of hydrogen peroxide with propylene to give propylene oxide.

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