摘要 |
A novel crystalline silica composition having uniform pore dimensions of approximately 6 Angstrom units is prepared by calcining a crystalline hydrated alkylonium silicate prepared hydrothermally from a reaction mixture containing as essential reagents, water, amorphous silica and a quaternary ammonium compound at a pH of at least 10. The crystalline silica, because of its uniform pore structure, is capable of making size-selective separations of molecular species, but neither it nor its silicate precursor exhibit ion-exchange properties.
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