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~(29)Si-NMR and ~1H-NMR were used to follow up the basic hydrolysis of tetraethyl orthosilicate(TOES) and the results showed that species of monomer,dimer,trimer,cyclic and polymer silicates wereformed.The monomer and dimer were favorable for the high activity of zeolite.XRD,~(13)C CP/MAS and~(29)Si NMR were used to trace the crystallization process of hollow titanium silicalite zeolites (HTS).Theresults showed that the induction period of HTS was 80 min,and subsequently it took next 10 min to formHTS and the remaining time of the crystallization period might function for cleaning up the pores and/orwashing off the impurities from the HTS zeolite.The catalytic oxidation performance of HTS zeolite isdifferent from that of the acid activity of zeolite in which the conventional definition of crystallinity doesnot reflect the catalytic oxidation activity proportionally.The synthesized HTS samples were character-ized by XRD,FT-IR,UV-Vis and Raman spectra.It was confirmed that Ti was incorporated into the zeoliteframework.The synthesized HTS samples revealed good repeatability and high activity for oxidation ofphenol into diphenol.
~ (29) Si-NMR and ~ 1H-NMR were used to follow up the basic hydrolysis of tetraethyl orthosilicate (TOES) and the results showed that species of monomer, dimer, trimer, cyclic and polymer silicates were formed. Monomer and dimer were favorable for the high activity of zeolite. XRD, ~ (13) C CP / MAS and ~ (29) Si NMR were used to trace the crystallization process of hollow titanium silicalite zeolites (HTS). The results showed that the induction period of HTS was 80 min, and following it took next 10 min to formHTS and the remaining time of the crystallization period might function for cleaning up the pores and / or or washing off the impurity from HTS zeolite. The catalytic oxidation performance of HTS zeolite is different from that of the acid activity of zeolite in which the conventional definition of crystallinity doesnot reflect the catalytic oxidation activity proportionally. The synthesized HTS samples were character-ized by XRD, FT-IR, UV-Vis and Raman spectra. It was confirmed that Ti was incorpo rated into the zeoliteframework. The synthesized HTS samples revealed good repeatability and high activity for oxidation ofphenol into diphenol.