摘要
利用凝胶分散法可以制备层间距大小不同,比表面不同,热稳定性和水热稳定性较好的层柱分子筛。以氧化硅为层间柱子的层柱分子筛的净层间距可达3.0～4.0nm;比表面最高可达450m^2/g;蒙脱土、云母-蒙脱土与硅交联后,DTA曲线上重结晶温度分别是950和1030℃。此外,对交联机理和层柱分子筛的稳定性作了初步探讨。
The pillared clays may be expected as a potential new type FCC catalyst. Some pillared clays with various layer separations and surface areas were prepared by gel dispersion method, especially silica cross-linked clays which cannot be prepared by conventional method. The layer separation of the silica cross-linked clays prepared by dispersion method has reached 3.0-4.0nm, the DTA recrystallization temperatures of silica cross-linked montmorillonite (Si-CLM) and silica cross-linked rectorite (Si-CLR) are 950 and 1030℃ respectively.The surface area of Si-CLM decreases by 70m2/g after calcined at 500℃ for 2 h, but that of Si-CLR retains under the same preparation and treatment conditions. The hydrothermal stabilities of these pillared clays have the similar regularity. The different stabilities of Si-CLM and Si-CLR may be attributed to different structures of clays. At certain range, different pillars affect only the thermal stability slightly, but the kinds of clay give significant effect on the stability of pillared clays.
