| abstract |
Molecular sieve compositions are prepared by extracting aluminum and substituting titanium and/or iron for extracted aluminum to give molecular sieve products containing framework titanium and/or iron atoms. The process of preparing the titanium and/or iron-containing molecular sieves involves contacting a starting zeolite with a solution or slurry of a fluoro salt of titanium and/or iron under effective process conditions to provide for aluminum extraction and substitution of titanium and/or iron. |