A new method of modification of TS-1 by weak base (aqueous NH3) treatment leads to formation of bigger crystals and generation of internal hydroxyl groups as evident by SEM and IR (hydroxyl region). All the catalysts were characterized using, XRD, N2-sorption, UV-VIS, FT-IR and SEM. Activity of the modified and unmodified TS-1 were compare in the hydroxylation of phenol to hydroquinone and catechol in presence of aqueous H 2O2. A ratio of hydroquinone to catechol over modified, (TS-1(33)/OH1 and unmodified, TS-1(33) catalysts were 1.40 and 1.15, respectively, using H2O as solvent, and 2.01 and 1.68, respectively, using MeOH as solvent. Modification of TS-1 with strong base (e.g. NaOH) causes decrease in crystallinity, and hence decreases the conversion of phenol and selectivity of hydroquinone. A new mechanism controlling the product selectivity is proposed.
|Number of pages||8|
|Journal||Studies in Surface Science and Catalysis|
|Publication status||Published - 2004|
- Microporous zeolite
- Titanium silicate-1
ASJC Scopus subject areas
- Physical and Theoretical Chemistry