Abstract: Titanium-silicon molecular sieve/geopolymer composite microspheres (TS-1@GQ) were prepared by in situ growth method using geopolymer microspheres (GQ) modified with polyethyleneimine (PEI) as carriers. The effects of PEI concentration on the catalytic performance of TS-1@GQ were investigated, the optimal TS-1@GQ was characterized by scanning electron microscope (SEM), X-Ray diffraction (XRD), Fourier transform infrared spectroscopy (FT-IR) and X-ray photoelectron spectroscopy (XPS), and its catalytic performance for the preparation of 1,2-epoxyhexane from 1-hexene was also evaluated. The results showed that the loading of TS-1 molecular sieves on the surface of TS-1@GQ could reach 11.43% when the PEI concentration was 0.003 mol/L. At the reaction temperature of 25 ℃, when the dosage of TS-1@GQ was 0.02 g, and n(1- hexene): n(H₂O₂) was 1: 1, the conversion rate of 1-hexene could reach 13.19%, and the selectivity of 1,2-epoxyhexane could reach 95.88%. In addition, the catalyst also showed good recyclability.

Key words: titanium-silicon molecular sieve, geopolymer microspheres, 1-hexene, 1,2-epoxyhexane