Hydrothermal Stability of Meso-microporous Composites and Their Catalytic Cracking Performance

Meso-microporous composites show great promise for catalysis because of their variously-sized porous structures. A series of composites containing uniform mesopores and MFI zeolitic channels were prepared by a template-free sol-gel method. The composite containing silicalite-1 structures was found to be much more hydrothermally stable than MCM-41. The composites with ZSM-5 structures showed higher catalytic activity and resistance to deactivation than commercial HZSM-5 in the catalytic cracking reaction of 1,3,5-triisopropylbenzene. The conversion and catalytic cracking product distribution of 1,3,5-triisopropylbenzene depended highly on the mesopore size of the composites. Higher conversions and small molecule cracking products were obtained using composites with smaller mesopores.

摘要：采用无模板剂的溶胶凝胶法 制备了一系列具有均一介孔和 MFI 沸石微孔的复合材料. 与 MCM-41 相比, 包含 silicalite-1 沸石结构的复合材料的水热稳定性得到显著改善. 1,3,5-三异丙苯的催化裂化反应结果表明, 与商品 HZSM-5 沸石相比, 包含 ZSM-5 沸石结构的复合材料具有更高的催化活性和抗积炭性能. 三异丙苯的转化率和裂化产物的分布主要取决于介孔-微孔复合材料的介孔孔径, 较小的介孔孔径有利于提高转化率和生成更多小分子裂化产物.

Graphical abstractMeso-microporous composites prepared from a ZSM-5 precursor xerogel generally gave higher catalytic activity and had better resistance against deactivation than commercial HZSM-5 in the catalytic cracking reaction of 1,3,5-triisopropylbenzene.Figure optionsDownload full-size imageDownload as PowerPoint slide