| 摘要 |
The present invention relates to silica/zeolite composite materials in spherical form and the process for their preparation which occurs by the dispersion of submicronic particles of titanium silicalite, beta zeolite, or mixtures of beta zeolite with titanium silicalite, in a silica sol synthesized by acid hydrolysis of silicon alkoxides; the hybrid sol thus obtained, subjected to emulsification and gelation techniques in organic mediums, produces these materials in a spherical form with an average diameter of between 20 and 150 mu m and containing up to 70% by weight of titanium silicalite, beta zeolite or mixtures of titanium silicalite/beta zeolite. The materials of the invention, having a high mechanical resistance and characterized by a surface area of between 300 and 800 m<2>/g, are applied as catalysts; in particular, those consisting of titanium silicalite or mixtures of titanium silicalite/beta zeolite are advantageously used in oxidation reactions of organic compounds with hydrogen peroxide. |
