| 摘要 |
This invention relates to novel silicon enhanced aluminas (SEAL) and processes to prepare them. The SEAL compositions have a bulk empirical formula of Al2-xSixO3Fx where x varies from about 0.01 to about 0.5. This SEAL material has a three-dimensional pore structure with the pores having diameters in the range of about 20 to abut 300A, a crystal structure characteristic of alu-mina, and where the surface of the SEAL has a higher silicon concentration than the interior of the SEAL. The SEAL is prepared by contacting an alumina with a fluorosilicate salt. This SEAL can be calcined to give a calcined seal with a formula Al2-xSixO3Fy where x is as defined above and y varies from 0.01 to x. The calcined SEAL contains both strong and weak acid sites. These SEAL compositions are useful as hydrocracking catalysts. |
