Siliceous molecular sieves having low acid activity and process for preparing same
US5262144A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Dec 26, 1991 |
| Grant date | Nov 16, 1993 |
| Priority date | — |
| Expiry date | Dec 26, 2011 |
Classification
- Technology area (CPC B)Performing Operations; Transporting
- CPC primaryB01J20/186
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
Abstract
The present invention relates in general to highly siliceous zeolitic molecular sieve adsorbent compositions having reduced catalytic activity and to the process for preparing such compositions. The number of acid sites in the so-called silica molecular sieves is very low, but exhibit a disproportionately high acid activity. In a variety of adsorptive separation applications in which the hydrophobic character of these molecular sieves is important, undesirable catalytic conversion of one or more of the adsorbates is frequently encountered. This acid activity is effectively eliminated by incorporating a stoichiometric excess with respect to the aluminum content of the molecular sieve of an alkali metal compound into the molecular sieve followed by calcining the loaded silicalite at temperatures of at least 750.degree.C. The adsorbent is particularly useful in separations of materials which are subject to catalytically initiated reactions, e.g., olefins and alcohols.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.