In-depth understanding the role of seeds in the synthesis of TS-1

The role of the seed in the seed-induced synthesis of TS-1 zeolite process was investigated in detail. The results revealed that the seed not only reduced the crystal size as reported previously but also promoted the incorporation of titanium atoms into the framework of TS-1 zeolite. Systematic investigations of the depolymerization behavior of TS-1 seeds in the tetrapropylammonium hydroxide (TPAOH) solution showed that the particle size and amount of TS-1 seeds directly affected the degree of depolymerization. Interestingly, the obtained TS-1 also had a similar catalytic performance when the completely-depolymerized seed species instead of seed crystals were added to the synthesis system. Meanwhile, the XRD pattern and IR spectra results showed that there were not any MFI framework units in completely-depolymerized seed species. Consequently, the effective ingredient of seeds was the species that had been depolymerized in the TPAOH solution.